Science Grade 10

SCIENCE

Lesson 1: Theory of Plate Tectonics

• Earth began as a single landmass or supercontinent called Pangaea

• The term Pangaea comes from the Greek words pan which means “all” and gaea which means “Earth”.

• Pangaea literally translates to “all of Earth” or “all lands”

• It was surrounded by a vast sea or super ocean called Panthalassa, which means “all seas”

• Tectonic is a term derived from a Greek word tekton which means “carpenter” or “builder”

• Describe the movement of the lithosphere

• Also called lithospheric plates

• Are massive, irregular slab of solid rocks that envelope the surface of Earth.

Theories of Plate Tectonics

1. Contraction theory

• proposed in the early 20^th century.

• this theory suggested that as the Earth cooled after its formation, its surface contracted and wrinkled, with these wrinkles being the mountain ranges on Earth’s surface

• EDUARD SUESS, an Austrian geologist, made an analogy between the wrinkles on the surface of a dried shrunken fruit and the mountains on the surface of a cooling Earth

2. Continental Drift Theory

• Proposed by Alfred Wegener in his book “The Origins of Continents and Ocean in 1915.

• Explained that about 1, 100 million years ago, there was a super continent named Rodinia, which predated Pangaea

• During the late Triassic period, Pangaea began to break up into a smaller supercontinent called Laurasia and Gondwanaland which move to the northern and southern extreme of the planet

• During the history of Pangaea’s formation, the now known North America smashed into northwestern Africa forming a vast mountain range.

• As Pangaea continued northward and crashed into the ocean floor of Panthalassa, it created a chain of mountain ranges extending from Alaska to Southern South America

• At around 250 mya, Pangea began to break apart forming a valley that is now called Atlantic Ocean

3. Seafloor Spreading Theory

• Proposed by an American geologist Harry Hess in 1960s.

• It says that the seafloors or ocean floors, not the continents move and carry the continents along.

Lesson 2: Mechanism of Plate Movements

• The plate tectonics is regarded as the most important theory ever developed in the field of geology. 

• There are TWO major thoughts that were raised to explain the mechanism of tectonic plates. These thoughts are heat loss and gravity which can be explained using the MANTLE CONVECTION THEORY and the SLAB PULL THEORY.

2 Major Ideas that explains the mechanism of tectonic plates

1. Mantle Convection Theory

• A process where can be transferred from one place to another.

• A method of heat transfer that is usually observed among fluid molecules (gas and liquid).

• Warm less dense material rises

• Cooler more dense material sink

• Fluids expand and become less dense when heated. In effect, the less dense fluid rises away from the heat source.  As it rises, it pulls cool fluid down to replace it.

• As the “pulled” fluid becomes heated, it also rises and pulls down more cool fluid creating a cycle that stop only when the heat is evenly distributed throughout the fluid.

• Arthur Holmes (1929)

• Using Wegener’s observations, Holmes suggested that as the mantle becomes heated, its density decreases and eventually rises up. 

• He added that when the material cools it, it would sink, exhibiting a circling behavior that he describes like a conveyer belt

• According to Holmes, the pressure of the heated magma broke the continents apart forcing the pieces to DRIFT in opposite directions. He further speculated that when the materials sank, continents will be brought back together again.

• Tectonic plates are moved passively by convection currents in Earth’s mantle.

• Mantle rocks near the Earth’s core become extremely hot making them less dense than the cooler mantle rocks in the upper layers. In effect, hot rocks rise and the cooler rocks sink.

• The convection currents push the magma up, forming new crusts and exerting a lateral force on the plate, pushing it apart to create seafloor spreading.

2. Slab Pull Theory

• This theory states that gravity and the plates themselves are the ones responsible for the plate tectonics through SUBDUCTION process.

• Subduction zones exist at the outer edges of plates where rocks are older. Hence, they are cooler and denser compared to those located at the inner layers.

• The old rocks or slabs also subduct or sink into the mantle below due to gravitation forces. 

• As the slab is pulled down into the mantle, it drags the rest of the plate along, causing tectonic plate movement. A very dense slab will sink faster than a less dense slab because of the gravitational pull and it will exert greater force on the plate to attached to it.

• The Slab Pull Theory believes that mantle convection is not the cause of plate tectonics but rather, it is a product of subduction.

Lesson 3: Plate Boundaries

• Region between plates

• Plates may move toward each other (converge), move apart(diverge), or move past one another

Types of Plate Boundaries

1. Divergent Plate Boundary

• When two plates move away from each other, a gap or rift between them is created.  If the gap eventually widens, it then evolves into a rift valley. 

• Divergent boundaries between oceanic plates produce mid-oceanic ranges, the mountain ranges formed underwater.

• Any continent or landmass above a divergent plate boundary will be torn apart into distinct landmasses. Surrounding waters will fill the space between them and later become an ocean.

2. Convergent Plate Boundary

• Occur when two plates slide toward each other and form either a subduction zone (if one plate moves underneath the other) or an orogenic belt (if the two simply collide and compress)

• Orogenic belt – region of deformed rocks

• 3 Kinds of Convergence

1. Oceanic-oceanic

• Marina Trench

• When two oceanic plate collides, a subduction zone is formed

2. Oceanic-continental

• In an oceanic-continental subduction, the oceanic plate goes down. As the denser oceanic plate subducts beneath the continental plate and descends into the mantle, the temperature increases, causing the rocks to melt and form magma.

• Andes Mountain of South America

3. Continental-continental 

• When two continental plates collide, no subduction happens. Instead, the continents suture themselves. The continental crust buckles and rocks pile up, creating mountain ranges.

• Alps Mountain Range

3. Transform Plate Boundary

• The plates slide against one another in opposite directions. No mountains or volcanoes are produced. Instead, earthquakes result from the movement of plates and release massive amounts of energy. 

• Earthquakes- refers to the shaking of Earth as a result of the breaking or shifting of the rocks of the tectonic plates.

• Dip slip – movement of faults

• Faults – crack on the Earth’s crust

1. Normal – hanging wall goes down

2. Reverse – hanging wall goes up

3. Strike-slip – slides 

Lesson 4: Evidence of Plate Movement

• Wegener did not received appreciation for his work and even after his death in 1930, the continental drift theory was regarded as improbable and ridiculous.

• With the discoveries of magnetic reversals during 1950s, Wegener’s theory was accepted and became the basis for the Plate Tectonics Theory.

Evidences of Plate Movements 

1. Paleontological Evidence

• Fossils of two land-dwelling reptiles, Lystrosaurus and Cynognathus, that lived during the Triassic Period have been unearthed in various continents, and their fossils are so numerous that they account for a major percentage of the bones recovered at some fossil beds.

• Antonio Snider Pellegrini

• A French scientist, proposed used identical plant fossils found in coal beds of Europe and US to support his idea that all continents were once connected during the Pennsylvanian Period (314-280 mya).

• He attributed the supercontinent break up to great flood during the time of Noah. 

•  Supporters explained that fossils of seed fern Glossopteris are too large to be dispersed across the ocean by the winds.

2. Evidence from Glaciation

• The till deposits indicate erratic glacier motion but they were fitted together like jigsaw puzzle, continents reveal as much more streamlined motion of the glacier from Southern Africa and Northern Australia outward

• Glaciation or glacial period is an interval of time within the ice age that is marked by colder temperature and glacier advances.

• During the latter part of Paleozoic Era (about 300 mya), glaciation occurred in the large part of the continents found in the southern hemisphere.

• In South America, India, and Australia, the iced appeared to have moved inland from the oceans, a phenomenon quite difficult to happen unless there was a landmass where the ocean basins now exist.

3. Evidence from structure and rock type

• Geographers noticed that the coastlines of several of the present-days continents would perfectly fit together, particularly Africa and South America.

• The Rift Valleys of Africa are also good evidence for the breakup of Pangaea.

4. Evidence from Paleoclimates

• Paleoclimatology: is the study of the extended climatic conditions of past geologic ages

• Wegener reconstructed old climatic zones using the distribution of specific rock types to determine the distribution of climates in ancient times. 

• For instance, glacial till and striations indicate polar climate near North and South Poles while sand dunes and coral reefs represent desert and tropical climates. 

Lesson 5: The Internal Structure of the Earth

• Lithosphere: outer solid part of the planet includes Earth’s crust as well as the underlying cool, dense and rigid upper part of the upper mantle. It extends from the surface of Earth to a depth of about 70- 100 km

• Asthenosphere: a high viscous, hotter, and ductile region of the upper mantle that is involved in plate tectonic movement and isostatic adjustment

Layers of the Earth

1. Crust

• is the outer most layer of the earth. It is the thinnest layer as it makes up only 1 percent of earth

•  The average composition of the crust has been identified from scientific analyses of rocks and minerals taken from the surface or underground. 

• The Mohorovicic discontinuity (Moho), which separates the crust from the mantle, was discovered by a Croatian seismologist Andrija Mohorovicic in 1909.

2. Mantle

• The largest area of earth that is composed of iron, aluminum, calcium, magnesium, silicon, and oxygen.

•  About 80% of the planet’s mass is concentrated on mantle and most of the internal heat of Earth is located in this layer including the magma chamber that drives volcanic processes. Average temperature inside the mantle is about 3,700°C, although it has different temperatures at different depths.

• Upper mantle is seen as highly viscous layer which lies between the crust and the lower mantle.  Rocks in the upper mantle are cooler and brittle enough to break under stress.

• On the other hand, rocks at the lower mantle are hot and soft. When subjected to force, they do not break instead they just flow along their region

3. Core 

• The inner most layer which is separated into the liquid outer core and the solid inner core.

•  Earth’s core is the planet’s source of internal heat because it contains radioactive materials which release heat as they break down into more stable substance. It is composed mainly of an iron-nickel alloy. 

• Outer core: regarded as an all of very hot metals. It is made up of iron, some nickel, and about 10% Sulphur and oxygen. The temperature in this zone is about 5,000 °C so it remains in its liquid state.

• Inner core: can be found at the deepest region of the planet. It is characterized by an extremely high temperature of about 5,000- 6,000°C or even higher than the temperature at the sun’s surface. The inner core is very important region as the intense heat reflected from it mobilizes the materials of the outer core and the mantle

Atmosphere

• The atmosphere is the thin gaseous sphere that envelopes the lithosphere. 

• The present atmosphere is composed of 78% nitrogen (N), 21% oxygen (O2), 0.9% argon, and trace amount of other gases

• The atmosphere is divided into layers according to differences in the pattern of temperature as one goes to higher altitude. From the bottom, these are the TROPOSPHERE, STRATOSPHERE, MESOSPHERE and THERMOSPHERE

Layers of the Atmosphere

1. Troposphere

• This is the lowest part of the atmosphere - the part we live in. It contains most of our weather - clouds, rain, snow

• The troposphere contains about 75% of all of the air in the atmosphere, and almost all of the water vapor (which forms clouds and rain)

2. Stratosphere

• It contains much of the ozone in the atmosphere. The increase in temperature with height occurs because of absorption of ultraviolet (UV) radiation from the sun by this ozone.

• By absorbing dangerous UV radiation, the ozone in the stratosphere protects us from skin cancer and other health damage.

3. Mesosphere

• The region above the stratosphere is called the mesosphere. Here the temperature again decreases with height, reaching a minimum of about -90°C at the "mesopause"

4. Thermosphere

• The thermosphere lies above the mesopause, and is a region in which temperatures again increase with height. This temperature increase is caused by the absorption of energetic ultraviolet and X-Ray radiation from the sun.

5. Exosphere

• The region above about 500 km is called the exosphere. It contains mainly oxygen and hydrogen atoms.

Biosphere

• The biosphere is the sphere that encompasses all life forms on earth from the smallest phytoplankton to the biggest mushroom

Lesson 1: Landforms

• Geomorphology - scientific study of landforms and the processes that shape them

• Topography - study of the current terrain features of a region and the graphic representation of a particular landform on a map

• Landforms

• natural physical features on the surface of Earth

• water, wind, ice and the tectonic plates of Earth

Types of Landforms

1. Aeolian Landforms

• formed by the chemical and mechanical action of the wind

• Greek god of the winds, Aeolus

• Different aeolian landforms

1. Dunes - mounds or small hills made up of sand

2. Loess 

• predominantly silt-sized sediment formed by the accumulation of windblown dust

• yellowish or brownish in color and it exhibits “cat steps”

• Europe and Mississippi Valley and Asia

3. Mushroom rocks

• Rock pedestal

• natural occurring rock that resembles the shape of a mushroom

• Mushroom Rock State Park in Kansas, US

• Aeolian Landforms: Depositional

1. Erg

2. Ripples

3. Barchan

4. Longitudinal Dunes

5. Transverse Dunes

6. Star Dunes

2. Erosional Landforms

• created from exclusively erosional and weathering activities

• Examples

1. Mesas

• Table mountains

• elevated areas of land with a flat top and sides 

• cap rock: resistant rock

2. Buttes

• covers a smaller amount of area when compared to a mesa

• French word means “hillock” or small hill

3. Canyons

• Gorge

• deep ravine between cliffs 

• canyons were not produced by tectonic activities or natural disasters but were influenced by water and wind erosion

3. Mountainous and Glacial Landforms

• exhibit slopes, summit area, and local relief

• rise higher than the rest of their surroundings

• Types

1. Volcanoes

• controlled by geological processes that forms them and continually act on them after their formation

• vent: opening at the top

2. Hills

• elevated portions of lands that are formed by geologic activities such as faulting

• smaller than mountains

3. Valley or Dale

• low-lying area of land situated between hills or mountains

• vale, dell, mountain cove, hollow and coon or hanging valley.

Lesson 2: Volcano

• Geomorphology - study of the relief features of Earth’s crust

• Volcano is an example of extrusive volcanism

• 3 Primary geologic forces

1. Diastrophism - vertical and horizontal movement of the crust that typically produces the mountains

2. Erosion - physical removal of rock or wearing down of landmasses

3. Volcanism - phenomenon related to the various processes associated with the surface discharge of magma or hot water and steams

• Volcano - cone-shaped hill or mountain formed by the extrusion of lave or ejection of rock fragments from a vent

• Derived its name from vulcano, an island off Sicily named after the Roman god of fire, VULCAN

• 859 active volcanoes in the world, more than 75% of them are located in the Circle of Fire

Theories of Volcanism

• Plate tectonics is a scientific study of the origin and arrangement of the broad structural features of the Earth’s surface known as the LITHOSPHERE

• Another factor that contributes to the planet’s temperature is the presence of natural radioactivity in rocks

• Convection currents are formed and caused the plates in the crust to move

• Volcanoes are formed when hot materials such as magma from the below rises and leaks into the crust

Features of a Volcano

1. Cone - most striking part of the volcano

2. Fissure - elongated fracture or crack on the Earth’s crust from which lava erupts 

3. Conduit - passage way through which magma travels to reach the Earth’s surface 

4. Vent - opening where volcanic materials are released

5. Crater - bowl-shaped depression at the top of the volcano where the vent is located

6. Flank - side of the volcano

7. Summit - the highest point or apex of a volcano

8. Magma chamber or reservoir - underground compartment where the magma is stored

Volcanoes

1. Inactive or dormant 

• The volcano is declared inactive or dormant if the last traces of volcanic heat disappear and if it has not erupted in 2000 years

• Some extinct volcanoes in the phil. are Mt. Butay and Mount Guinsiliban on Camiguin Island 

2. Active

• currently erupting or shows signs of unrest activities

• Most active volcano is the Mayon Volcano in Albay - it has 50 eruptions and the most recent is on January 2018. 

3. Extinct 

• Volcanoes with no record of eruptions. They have not shown any signs of activity, so it is highly unlikely that they will be expected to erupt

• Some extinct volcanoes in the phil. are Mt. Butay and Mount Guinsiliban on Camiguin Island. 

Potential Volcano Related Hazards

• Lahar: rapidly flowing thick mixture of volcanic sediments and water

• Gases

• Water vapor (H₂O) 

• Hydroden sulfide (H₂S) 

• Sulfur dioxide (SO₂) 

• Carbon dioxide (CO₂) 

• Nitrogen (N) 

• Methane (CH₄)

• Lava flow: molten rocks that move down the slope of volcanic vents

• Pyroclastic Surges: volcanic materials of gases, ash, rock fragments, and water extruded above the ground

• Pyroclastic flow

• from Greek Words pyro (fire) and clast (broken)

• rock fragments spewed during volcanic eruptions

Types of Volcanoes

1. Composite

2. Cinder Cone

3. Shield

Volcanoes

• Volcanologists use volcanoes to study what is going inside the Earth. 

• Dramatic and powerful explosions tell us that the Earth is a dynamic planet. 

• Volcanologist cannot predict when eruption occur but they can warn people if there is imminent danger and advise them immediately. 

• Howel Williams

• Conduct an extensive research and study on volcanoes led to the development of volcanology as a new field in Modern Science.

• He is known as “Father of Modern Volcanology”. 

Lesson 3: Earthquakes

• The Philippines is a large archipelago consisting of more than 7100 islands. 

• It is located along the Western Pacific Basin and lies between two tectonic plates whose interactions give rise to geologic processes like tectonic earthquakes, volcanism, and mass movement. 

• For example, the earthquake in Bohol in 2013, the landslide in 2006 and volcanic eruption of mount Pinatubo 1991 brought about numerous deaths, destruction of properties, dislocation of people, and irreparable damage to environment. 

Earthquakes

• Earthquake - natural phenomenon that is characterized by a sudden, violent shifting of massive plates underneath Earth’s surface. This movement of plates releases stress that generates along geologic faults. 

• Hypocenter (focus) - place beneath the surface from which an earthquake initiated

• Epicenter - Directly above the focus

• Fault - crack across which the rocks have been offset first

• Foreshocks - small earthquakes that commonly precede a major earthquake

• Aftershock - After a major earthquake, smaller earthquakes occur

• Seismograph - instrument used to study earthquake which records the shaking of earthquake waves

• Seismogram - records

Types of Earthquakes

1. Tectonic 

• generated by the sudden displacement along faults in the solid and rigid layer of the earth

• happen when the shifting of the earth’s plate is driven by the sudden release of energy within some limited region of the rocks of Earth

2. Volcanic

• occurs in volcanic regions and can serve as an early warning of volcanic eruptions

• caused by either the injection or withdrawal of magma in response to the changes in pressure in the rock where the magma has experienced stress

3. Collapsed

• caused by seismic waves produced from the explosion of rock on the surface

• It is small earthquakes located underground and in mines that are caused by the integrations of the roof of the mine or cavern or by massive land sliding

3 Types of Faults

1. Normal

2. Reverse

3. Strike slip

Hazards brought by earthquakes

1. Ground breaking - cause mild or severe damage to properties or structures

2. Ground subsidence 

• grounds sink due to earthquake

• Subsidence: lowering of land due to various causes

• Any structure where this event happens can be swallowed. In another instance, a gaping hole can be left

3. Liquefaction

• strength and hardness of the soil are reduced

• the groundwater mixed with ground soil that makes the soil less stable

4. Fault Creep - Slow, more or less continuous movement occurring on faults due to ongoing tectonic deformation

5. Lateral Spread or flow - landslides that commonly form on gentle slopes and that have rapid fluid-like flow movement

6. Tsunami

• Japanese word for tidal wave or big wave in the port

• Coined by fishermen who turned to their ports after their villages had been devastated by a giant wave while the fishermen had not seen any waves in the open sea

• Generated when the ocean floor abruptly deforms and vertically displaces the overlaying water

• The height and strength of the waves depend on the duration and intensity of ground movement under the water

• Causes of Tsunami

1. Underwater earthquakes due to the crustal movements

2. Underwater volcanic eruptions

3. Landslide triggered by falling rocks, corals, or ice

4. Underwater explosions that may either be chemical or nuclear in nature

7. Seiches - large wave that moves up and down instead of forward

8. Landslides - the movement of rock, earth, or debris down a sloped section of land

Lesson 1: The Electromagnetic Spectrum

• James Clerk Maxwell (1862)

• Predicted the existence of EMW. 

• “Father of EM Theory”

• It was successfully proven by German Physicist HEINRICH HERTZ After Maxwell death

• Our Sun is a source of energy across the full spectrum, and its electromagnetic radiation bombards our atmosphere constantly.

• Earth's atmosphere protects us from exposure to a range of higher energy waves that can be harmful to life

• EM Spectrum: range of all types of EM radiation

• Radiation: energy that travels and spreads

• 2 types of electromagnetic radiation

• the visible light that comes from a lamp in your house

• the radio waves that come from a radio station

7 Types of Electromagnetic Waves

1. Radio wave

• lower frequencies than microwaves

• Radio-wave communications signals travel through the air in a straight line, reflect off of clouds or layers of the ionosphere, or are relayed by satellites in space

• radio captures radio waves emitted by radio stations, bringing your favorite tunes. Radio waves are also emitted by stars and gases in space

2. Microwave 

• extremely high frequency radio waves, and are made by various types of transmitters

• short wavelengths: 1 mm to 30 cm

• Microwaves cause water and fat molecules to vibrate, which makes the substances hot. So, we can use microwaves to cook many types of food.

• Mobile phones use microwaves, as they can be generated by a small antenna. (WIFI)

• fixed traffic, speed cameras, and for radar, which determine the range, altitude, direction, or speed of both moving and fixed objects, such as aircraft, ships, spacecraft, missiles, motor vehicles, and weather formations.

3. Infrared wave

• Infrared light

• human eye cannot see it, but humans can detect it as heat

• infrared absorbed by your skin causes the amplitude of vibration of molecules in your skin to increase. Your skin is warmed.

• Heat or thermal radiation

• A remote control uses light waves just beyond the visible spectrum of light-infrared light waves- to change channels on your TV

4. Visible light

• human eye can view

• human eye can detect wavelengths from 380 to 700 nanometers

• Fireflies, light bulbs, and stars

• It starts with red light and ends with violet light

5. Ultraviolet Radiation

• extending from the violet, or short-wavelength, end of the visible light range to the X-ray region

• emitted by the Sun and are the reason skin tans and burns

• hot objects in space

• undetectable by the human eye

• when it falls on certain materials, it may cause them to fluoresce—i.e., emit electromagnetic radiation of lower energy, such as visible light

• Many insects, however, are able to see ultraviolet radiation

6. X-ray

• see through a person's skin and reveal images of the bones beneath it

• imaging teensy biological cells and structural components of materials like cement to killing cancer cells

7. Gamma ray

• produced in the disintegration of radioactive atomic nuclei and in the decay of certain subatomic particles

• area of oncology to treat malignant and cancerous tumors during a process called gamma knife surgery

• beams of gamma rays are directed at tumors in order to kill cancerous cells

• imaging techniques in nuclear medicine for diagnostic purposes (gamma cameras)

• positron emission tomography (PET) scan: an imaging test that allows your doctor to check for diseases in your body

Lesson 2: Effects of Electromagnetic radiation

• Information is sent from place to place by means of radio waves. 

• We forecast weather using microwaves. Waves even invade our kitchen when food is cooked in a microwave oven. 

• X-rays and gamma rays are now used in medical diagnosis and treatment. 

• Ultraviolet rays are used as a medical sterilizing agent. 

• The hazards brought about by EM waves depend on their FREQUENCY

• The higher the frequency, the greater the energy of the radiation

Electromagnetic Radiation and Life

• Radiation may be ionizing or non-ionizing

• Ionization: process of removing electrons from neutral atoms

• lonizing radiation can produce molecular changes that can lead to damage in biological tissues

• Electromagnetic radiation

1. Ionizing radiation

• X ray and gamma ray

• Immediate effect: death or radiation burns

• Delayed effect: cancer or mutation, which may be on the person exposed to radiation or to his/her offspring

2. Non-ionizing radiation

• Less dangerous

• Radio wave, microwave, infrared light, visible light, UV ray

1. Microwaves cause cataracts

2. Far infrared waves are thermal

3. Shorter, near infrared waves are not hot at all - in fact you cannot even feel them.

4. Excessive exposure to visible light, especially in the blue region, can cause eye damage

5. Lasers can cause blindness

6. Too much exposure to ultraviolet rays burns our skin and produces the so-called sun tan

7. UV rays can also cause skin cancer.

8. Ultraviolet rays can damage the retina

Electromagnetic Radiation and the Environment

• Greenhouse effect: gases in Earth's atmosphere trap the Sun's heat

• Enhanced effect: The greenhouse effect resulting from the increased concentration of greenhouse gases of human activity

• Anthropogenic greenhouse effect

• Enhanced greenhouse effect leads to global warming

Lesson 1: Reflection

• Light - electromagnetic radiation that has properties of waves and particles

• Image formation by mirrors, the twinkling of stars, the beautiful colors of a rainbow, bending of light by a medium

• Echo – reflected sound wave

• Reflection - when light bounces off an object

• If the surface is smooth and shiny, like glass, water or polished metal, the light will reflect at the same angle as it hit the surface.

• Example of invisible light reflection: surface of a smooth pool of water, where incident light is reflected in an orderly manner to produce a clear image of the scenery surrounding the pool\

• Two types of Reflection

1. Regular or Specular: reflection from smooth surfaces

2. Diffuse: rough surfaces

• Incident light ray (incoming light wave) - which lands upon the surface is said to be reflected off the surface

• Reflected ray – the ray that bounces back

• Normal - a perpendicular drawn on a reflecting surface

• The law of reflection: determine the reflection of incident light rays on reflecting surfaces

1. The incident ray, the reflected ray and the normal all lie in the same plane

2. The angle of incidence = Angle of reflection

Mirrors and Reflection of Light

2 types of Mirrors

1. Plane Mirror

• Flat surface

• Ordinary mirror

2. Spherical Mirror

• Example: shiny spoon

• Concave or convex

1. Concave

• Inside curve of a spoon

• Can produce real or virtual images, depending on the distance between the mirror and the object

• The image may be larger, the same size as, or smaller than the object

2. Convex

• Curve outwards, like the back side of the spoon 

• The image formed is never real because the reflected rays spread out from the mirror

• Images formed by a convex mirror are always virtual, upright, and smaller than the object.

Uses of Concave and Conex

1. Concave Mirror

• used in certain types of astronomical telescopes called reflecting telescopes

• The mirrors condense lots of light from faint sources in space onto a much smaller viewing area and allow the viewer to see far away objects and events in space that would be invisible to the naked eye

• Concave lenses are used in eyeglasses for people who are nearsighted (those who have trouble seeing things that are far away)

2. Convex Mirror

• shop security and rear-view mirrors on vehicles because they give a wider field of vision

• Convex lenses are used in glasses for people who are farsighted (those who can’t see things very well up close)

Lesson 2: Refraction

• This bending by refraction makes it possible for us to have lenses, magnifying glasses, prisms and rainbows.

• Without refraction, we wouldn’t be able to focus light onto our retina.

• Retina - part of the eye that receives light and send these signals on to the brain for visual recognition

• Refraction - bending of light as it passes from one medium to another

• Since the surface of the glass is curved, the water in the glass also acts as a magnifying glass, slightly enlarging the spoon

• Cause of refraction: Change of Speed Results in Change in Direction

• Light refracts whenever it travels at an angle into a substance with a different refractive index (optical density)

• When light travels from air into water, it slows down, causing it to continue to travel at a different angle or direction

Refractive Index

• Index of Refraction

• Describes how fast light travels through the material 

• Dimensionless

• Refractive index (n) =  Speed of light in vacuum (c)

        Speed of light in the medium (v)

• N = c/v

• C = 3x10⁸ m/s

• N₁ of air = 1.0003

Laws of Refraction

1. The incident ray, refracted ray, and the normal to the interface of two media at the point of incidence all lie on the same plane.

2. (a) When a ray of light passes obliquely from an optically denser medium to a less dense medium, it is refracted away from the normal. 

(b) When a ray of light passes obliquely from an optically less dense medium to a denser medium, it is refracted towards the normal. 

(c) When the incident ray is perpendicular to the interface, no bending of light ray occurs. 

3. Snell’s law, named after the Dutch astronomer and mathematician Willerbrord Snell, relates the index of refraction of two media and the angles from the normal using the equation:

n1 sinθ1=n2 sinθ2

n1= index of refraction of the incident medium

n2=index of refraction of the refractive medium

1= angle of incidence

2= angle of refraction

Shallowing Effect

• Effect of refraction

• Objects submerged in a liquid always appear to be shallower than they actually are

• The light coming from the objects changes angle at the surface of liquid, bending towards the liquid. It can be shown mathematically that the index of refraction is the ratio of the real depth to the apparent depth.

• N =   Real depth

     Apparent depth

• N of water = 1.33

Refraction of Light in Real Life

• Result of Refraction: Mirage and looming optical illusions

• A swimming pool always looks shallower than it really is because the light coming from the bottom of the pool bends at the surface due to refraction of light.

• Formation of a rainbow is an example of refraction as the sun rays bend through the raindrops resulting in the rainbow.

• When white light passes through a prism it is split into its component colors – red, orange, yellow, green, blue and violet due to refraction of light.   

Lesson 1: Living things and their environment

• Diversity: all variety of life that exists in Earth 

• Reproduction: process of humans breeding off springs

• Humans begin their lives as a cell

• a cell is created by a fusion of 2 sex cells

• Sex cells contain chromosomes that contain genetic information

• Morphology: study of form and structure of organisms

• Physiology: study of functions of organism

Male Reproductive System

• Role: produce and transport sperm cells

• Urethra: passes through the penis and carries urine and sperm

• Penis: external sexual organ of males which through sperms are delivered into female's body

• Testes: in which sperms are produced

• Testosterone: sex hormones

• Epididymis: on the back of each testicle where sperm stays for 2 to 4 days.    

• Vas deferens: tube that sperms pass through from the epididymis

• Scrotum: hangs from the penis which houses the testes and protects the sperm cells

Sperm Cells

• fertilizes the egg cell

• located in the testes

• Male have 2 testes inside the scrotum

• Parts of sperm cells: head (contains the chromosomes), neck, middle piece (contains the mitochondria), tail (movement)

• Glands 

1. Prostate gland - neutralizes acid in female's

2. seminal vesicles - rich in sugar 

3. bulbourethral gland - neutralizes the traces of acidic urine 

Delivery of Sperm Cell

• blood go through the penis making it erect

• sperms exit the penis through ejaculation

• after semen is deposited, the sperm swims until it reaches the egg cell

• 3.5 ml semen 300 to 400 million sperm cells

Female Reproductive System

Egg cells

• egg cells are the biggest cells

• Ovaries: one on each side

• Ovaries produce hormones called estrogen and progesterone

• Ovulation: produce one ripened egg every 28 days

• Eggs are stored in ovaries

• Fallopian tubes: from ovary to uterus, contain egg until fertilization, passageway of sperm cells to the egg

• Uterus or womb: located between the 2 ovaries, where the fertilized egg will develop

• If egg is unfertilized, the uterus shed and passes causing menstrual discharge

• Cervix: connecting the lower part of uterus to the upper portion of vagina

• Vagina or birth canal: from cervix to outside of the body

• Vulva: external genitalia 

• Role: produce egg cells and for child bearing

Egg Production

• 2 million egg cells

• ova, ovum, egg cells  

• 3-4 days for ovum to travel to fallopian tubes

• 24 to 48 hours to die

• The fertilized ovum called zygote will be implanted to the uterus

Female Reproductive Cycle

• monthly psychological cycles: ovarian and menstrual cycle

• Ovarian cycle: prepare the bodies to make pregnancy possible

• Ovulation: monthly release of ovum

• Ovarian cycle occurs in 2 distinct stages

1. Follicular

2. Luteal phase 

• Egg cells mature within follicles

• Follicles: cluster of cells that surrounds immature egg cells

• hormones regulate the completion of egg cell's maturation

• Follicle stimulating hormones and luteinizing hormones

• these hormones cause to produce estrogen

• Estrogen: acids the growth of ovum follicle

• when follicle burst, ovulation occurs

• the luteal phase begins

• Corpus luteum: yellowish mass of follicle cells

• Lh causes this to produce estrogen and progesterone

• progesterone: signals the body to prepare for fertilization

Menstrual Cycle

• 11 to 15

• Menstruation: monthly shedding of the lining of uterus

• dry and sticky: non fertile, creamy: semi fertile, clear: fertile

• Dysmenorrhea or menstrual cramps: throbbing or cramping pain in the lower abdomen

Lesson 2: Prevention, Detection, and Treatment of Sexually Transmitted Diseases

• STD: generally acquired by sexual contact

• may pass from person to person in blood, semen, or vaginal and other bodily fluids.

• There are generally no cure but There are treatment of sexually transmitted diseases.

Sexually Transmitted Diseases

1. Syphilis

• bacterium Treponema pallidum

• incubation period of about a few weeks to several months and occurs in several stages before it turns into dangerous condition

• anal sex and oral sex, as well as vaginal sex

• A painless sore known as a chancre 

• genitals, rectum, or mouth

• Congenital Syphilis: contracted by babies born to an infected mother

• Infected persons and their sexual partners must be tested and treated with antibiotics. Sexual activity must be avoided until disease is cured.

2. Gonorrhea

• Neisseria gonorrhea

• invades the epithelial lining of the vagina and the male urethra

• This results in a discharge called pus

• rectum, eyes, throat, and joints

• Sexually active women younger than 25 and men who have sex with men are at increased risk of getting gonorrhea.

• Men: burning sensation during urination, pain or swelling in one testicle and a pus discharge

• Women: vaginal discharge, painful urination, vaginal bleeding in between periods

• If untreated, could lead to pelvic inflammatory disease

• Antibiotics are used to treat the disease

3. Genital Herpes

• herpes simplex virus-2 (HSV-2)

• painful, itching lesions and blister-like eruptions in the genital area that occur 10 days after exposure to an infected sexual partner

• may stay dormant in the body but may activate due to stress or illness

• Condom use is advised by doctors. There is no cure

4. HIV

• Human Immunodeficiency Virus

• Attack cells that help the body fight the infection

• No cure but treatable with medicine

• Most people with HIV don’t have any symptoms for many years

• the virus stays in your body for life

5. AIDs

• Acquired Immunodeficiency Syndrome

• caused by a virus known as the Human Immunodeficiency Virus (HIV) which attack the immune system 

• contact with body fluids containing virus, sexual intercourse, sharing of contaminated needles, receiving of contaminated blood via transfusion, or birth from an infected mother

• weight loss associated with diarrhea, swollen lymph glands, chronic low-grade fever, fatigue, and night sweats

• susceptible to opportunistic infections such as pneumonia, tuberculosis, or fungal infection in the lungs and throat.

• There is no known cure for AIDS, but a prompt medical attention can reduce or delay the onset of serious complications.

Lesson 1: Nervous System

• It controls and interprets all the activities that happen in the body

• Functions

1. Gathers information both from the outside world and from inside of the body

2. Transmit information to the processing areas in the brain and spinal cord

3. Processes information to determine the best response

4. Sends information to muscles, glands, and organs so they can respond correctly

• keeps the body working properly despite the constant CHANGES that takes place around it

• These changes are called stimuli (singular: stimulus)

Basic Cells of the Nervous System

Neurons

• basic functional units of structure and function of the nervous system

• They carry information through the nervous system in the form of nerve impulses

• Parts of a Neuron

1. Dendrites - It receives and carry information TOWARD the body cell

2. Cell Body

• largest part of the neuron

• Contains the nucleus (a large dark structure), which control all the activities of the cell

3. Axon - It carries messages AWAY from the cell body

4. Myelin Sheath - covers the axon, which speeds up the travel of the nerve impulses

5. Schwann Cells - produce myelin or fat layer

6. Node of Ranvier - gaps or nodes in the myelin sheath

Parts and Functions of Nervous System

The Central Nervous System (CNS)

• command center of the entire body; it processes information and sends instructions to other parts of the body

• spinal cord provides the LINK BETWEEN THE BRAIN AND THE REST OF THE BODY

Brain

• important and delicate organ that is protected by and encased in a bone called skull

• The brain appears gray because it is mostly composed of gray matter, which is because of the presence of billions of cell bodies

• mass of the brain is about 1.4 kilograms only

• Our brain uses around 20 percent of our body’s total energy

• 3 Main Parts

1. Cerebrum

• makes up 85% of the human brain and largest part of the brain 

• surface of the cerebrum is called the cerebral cortex, which increases the surface area so that more thinking activities can occur

• shapes the attitudes, emotions, and even the personality of an individual

2. Cerebellum

• Left: knowledge, right: artistic

• second largest part

• located behind the brain stem 

• coordinates the actions of the muscles and maintains balance

• Balance, equilibrium, and posture are coordinated by the cerebellum

3. Brain Stem

• connects the spinal cords to the rest of the brain

• coordinates many survival functions of the body such as breathing, heart rate, sleep, and wakefulness

Spinal Cord

• tubelike organ of neurons and blood vessels

• located inside the backbone and is about 1.8 cm wide

• Impulses from the PNS are carried to the spinal cord, which then brings the message to the brain

Peripheral Nervous System

• The PNS links the central nervous system (brain and spinal cord) to the rest of the body

• made up of a network of bundled ropelike structures called NERVES, which extend or branch out from the central out from the CNS to the different organs of the body

• part of the peripheral nervous system that stimulates skeletal muscles under your conscious control is called SOMATIC NERVOUS SYSTEM

• The part of the peripheral nervous system that is not under the direct control of the conscious mind is called AUTONOMIC NERVOUS SYSTEM

• ANS: directs motor nerve fibers in smooth muscles, cardiac muscles, and the glands

• Autonomic Nervous System

1. Parasympathetic Division - most active under normal conditions; it keeps the body functioning even when the person is not active

2. Sympathetic Division

• dominates in times of physical and emotional stress

• controls the “fight-or-flight” response 

Lesson 2: Endocrine System

• Hormones: partially control or regulate the fast reactions and slow changes happening in your body

• Happiness Chemicals

1. Dopamine – Reward Chemical

2. Oxytocin – The Love Hormone

3. Serotonin – The Mood Stabilizer

4. Endorphin – The Pain Killer

• Hormones: chemical messengers that carry instructions to cells to change their activities

• Gland: organ whose cells secrete materials to the different parts of the body

• Endocrine Gland

• Endo means “within”, krinein means “separate”

• ductless glands that secrete hormones directly into either the bloodstream or the fluid around the cells

• brain, stomach, small intestine, kidney, liver, and heart

Endocrine System

• These hormones control nearly all the processes in your body

• body’s functions, from metabolism to growth and development, emotions, mood, sexual function and even sleep

• Hormones deliver their messages by locking into the cells they are targeting so they can relay the message

• Your endocrine system continuously monitors the amounts of hormones in your blood

• Homeostasis: self-regulating process by which an organism tends to maintain stability while adjusting to conditions that are best for its survival

• Endocrine system is made up of organs called glands

• Glands produce and release different hormones

• Hormones nearly affect every process in your body

1. Metabolism

2. Growth and development.

3. Emotions and mood.

4. Fertility and sexual function.

5. Sleep.

6. Blood pressure

Major Endocrine Glands

1. Hypothalamus

• At the base of the brain

• Link between the nervous system and the endocrine system

• Determine when to tell other glands, including the pituitary gland, to produce hormones

2. Pituitary Gland

• Hypophysis

• in the center of the skull

• Referred to as the “master gland” because it produces hormones that control many activities of the other endocrine glands

• made of two lobes, the anterior and posterior glands

3. Thyroid Gland

• under the larynx or voice box

• three hormones: triiodothyronine (T₃), thyroxine (T₄), and calcitonin

• Both T₃ and T₄ contain the element iodine

• maintaining heart rate, blood pressure, muscle tone, and reproductive functions

• An insufficient amount of these hormones in the body can lead to hypothyroidism, which causes weight gain, lethargy, and intolerance to cold

• Parathyroid Glands

• These four tiny glands control the level of calcium in your body

• release the parathyroid hormone

4. Adrenals

• The word adrenal means “above kidney”

• located at top each of your kidneys

• inner adrenal medulla and the outer adrenal cortex

• inner adrenal medulla

• produces adrenaline which plays an important role in the body’s coping mechanism

• part of the body’s emergency action team

• gives the body a strength that could be considered “superhuman”

5. Pineal Gland

• located near the thalamus of the brain

• produces melatonin (a hormone that causes you to feel sleepy)

• synchronizes daily rhythms, regulates body systems, and helps the body adapt to seasonal changes

6. Pancreas

• produces two types of hormones: insulin and glucagon

• Insulin: keeps the levels of sugar (glucose) in the bloodstream under control

• Glucagon: increases the level of sugar in the body by speeding up the conversion of glycogen into sugar in the liver

7. Ovaries 

• ovaries release sex hormones called estrogen, progesterone

8. Testes

• make sperm and release the hormone testosterone

Conditions and Disorders affect Endocrine System

1. Diabetes

• chronic (long-lasting) health condition that affects how your body turns food into energy

• Most of the food you eat is broken down into sugar (also called glucose) and released into your bloodstream. When your blood sugar goes up, it signals your pancreas to release insulin. 

• Glucose meter/ Glucometer

• 3 types of Diabetes

1. Type 1 diabetes: need to take insulin injection for lifetime 

2. Type 2 diabetes

• Insulin Resistance: The body produces minimal insulin or the body’s cell do not react to insulin, a condition

• 90% of diabetes cases

• Diet exercise, and taking antidiabetic tablets

3. Gestational diabetes

• Due to hormonal changes during pregnancy, a pregnant woman’s cell is less responsive to insulin

• As more glucose enter the placenta and is absorbed by the baby, it can lead to condition known as macrosomia or “fat baby”

2. Thyroid Disorders

• Hypothyroidism happens when the thyroid doesn’t produce enough hormones

• Hyperthyroidism occurs when it creates too many hormones.

3. Hypogonadism

• Low Testosterone

• In men, hypogonadism can cause erectile dysfunction

• testes do not produce enough of the sex hormone testosterone

4. Polycystic Ovary Syndrome (PCOS)

• irregular periods, abnormal hair growth, excess acne and weight gain

• The ovaries may develop numerous small collections of fluid (follicles) and fail to regularly release eggs.

• Having PCOS does not mean you can't get pregnant. PCOS is one of the most common, but treatable, causes of infertility in women.

5. Osteoporosis

• When a woman’s ovaries don’t produce enough estrogen, bones become brittle and weak

• People with an overactive parathyroid gland (hyperparathyroidism) may also have weak bones.

6. Dwarfism

• Pituitary dwarfism: body’s insufficient production of growth hormones

• Dwarfism is short stature that results from a genetic or medical condition

• Some people prefer the term "short stature" or "little people" rather than "dwarf" or "dwarfism."

• Disproportionate Dwarfism and Proportionate Dwarfism

Lesson 3: Infections of the Nervous System

1. Encephalitis is an acute infection and inflammation of the brain.

2. Meningitis is an inflammation of the meninges and the membranes surrounding the brain and the spinal cord.

3. Rabies is a viral infection transmitted through bites by infected animals such as dogs and cats.

4. Tetanus is a disease caused by certain bacteria found in soil contaminated with animal waste. It is often introduced into the body via open wounds

Nervous system and Neurodegenerative Disorders

• Neurodegenerative diseases are characterized by damage or death or death of neurons in specific parts of the brain or spinal cord which could lead to dysfunction and disabilities.

• 2 classes

1. Parkinson’s disease –is a progressive disease of the nervous system that affects the patient’s movement. It is named after English physician James Parkinson who first described the disorder.

2. Alzheimer’s disease- is a condition characterized by severe mental deterioration which get worse over time.

• Epilepsy is a brain disorder associated with seizures, involuntary movement, and loss of consciousness.

Lesson 1: Hersey-Chase Blender Experiment

• DNA or deoxyribonucleic acid – hereditary material in humans and other organisms

• Genetic material – molecule that bears genes and passed down from parents to children

Hersey-Chase Blender Experiment

• 1952, two American biologist; Alfred Hershey and Martha Chase conducted an experiment

• To conclude whether it was DNA or protein that was needed to infect the bacterium to produce more virus

• Is the DNA or protein the hereditary material?

• They used blender to detach the viruses from the bacteria

• The virus T2, a bacteriophage was used

• Viruses cannot reproduce without injecting its hereditary info to the host

• 2 different mediums, one containing the bacteria and T2 virus with phosphorus that is found in the DNA and one medium with the same virus and bacteria but with sulfur isotope that is found in proteins but not in the DNA

• It was seen that the medium with the phosphorus was potent with the bacteria, and the medium with the sulfur was with the viruses. This means that phosphorus that was found in the DNA is the genetic material that made it possible for the viruses to infect the bacteria.

Lesson 2: The Watson-Crick DNA Model: A double helix

Rosalind Franklin’s X-ray Diffraction

• British physicist and researcher from King's College in London

• studied the structure of DNA using a technique known as x-ray crystallography.

• "Unrecognized brain behind the DNA double helix associated with Watson and Crick,"

• November 1951, Franklin delivered a lecture to a group of scientists, including biologist James Watson, on the two forms of DNA: Type A (dry form) and Type B (wet form)

• Photo 51: x-ray diffraction photograph of DNA taken by Franklin in 1952. 

• Photo 51, was instrumental in the elucidation of the double-helical structure of DNA

• Hydrated DNA was exposed to an x-ray beam for more than 60 hours, which resulted in the scattering of its component molecules to produce an image useful in the creation of the three-dimensional structure of DNA.​

• she published her x-ray diffraction photographs of the DNA in 1953 in the same issue of Nature where the Watson-Crick model first appeared

• studies on the structures of the tobacco mosaic virus and the polio virus

• In 1958, four years before the Nobel Prize in Physiology or Medicine was awarded to Watson, Crick, and Wilkins, Rosalind Franklin died of ovarian cancer. She was 37.​

The Watson-Crick DNA Model: A double helix

• Deoxyribonucleic Acid (DNA) is a double-stranded, helical molecule.

• A and T, C and G

• James Watson (1928 - Present) and Francis Crick (1916 - 2004) realized that these pairing rules meant that either strand contained all the information necessary to make a new copy of the entire molecule, and that the aperiodic order of bases might provide a "genetic code". ​  

•   Rosalind Franklin (1920 - 1958) had earlier produced the first clear crystallographic evidence for a helical structure. 

• Crick went on to do fundamental work in molecular biology and neurobiology. 

• Watson become Director of the Cold Spring Harbor Laboratory, and headed up the Human Genome Project in the 1990s.

• On April 25, 1953, an article in the scientific journal Nature titled "Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid" was published by American biologist James Watson and English physicist Francis Crick. 

• This was the first published article that described the structure of the DNA as a double helix. 

• How the genetic information inside the nucleus of cells was stored and passed from one generation to the next.

• The model was based on the x-ray diffraction image taken by Rosalind Franklin and Raymond Gosling in 1952. 

• In recognition of the tremendous impact of the elucidation of the double-helix structure of DNA, James Watson; Francis Crick, and Maurice Wilkins were awarded the Nobel Prize in Physiology or Medicine in 1962.​

• The backbone of the helix consists of alternating sugars and phosphates, while the steps of the ladder are made up of nitrogenous base pairs.

• Hydrogen bonds connect the nitrogenous base pairs together, making the double helix highly stable.

Key Features of the DNA Model

1. The helix turns clockwise (a right-handed double helix).​

2. The backbones of the helix are in opposing directions (antiparallel chains).​

3. Nitrogenous bases are flat structures inside the helix.​

4. Bases are 3.4 angstrom units apart.​

5. Adenine pairs with thymine using two hydrogen bonds, while guanine pairs with cytosine using three hydrogen bonds (base complementarity).​

6. There are 10 bases every 360° turn.​

7. There are 34 angstrom units in every complete turn.​

8. The double-helix diameter is 20 angstroms.​

9. DNA follows a semiconservative mode of replication.​

Lesson 3: Griffith’s Transformation Experiment

Frederick Griffith

• The discovery of DNA can be traced back to the study made by a British medical officer in 1928.

• He studied two strains of the bacterium, a harmless strain (rough strain or R strain) and a pathogenic strain (smooth strain or S strain), that cause pneumonia

The Experiment

• Mice injected with the S strain died from pneumonic infection within a few days, while mice injected with the R strain continued to live.

• Griffith killed the S strain by heat injection and the mice survived. He also mixed the bacterial remains of the S strain with the living R strain.

• Griffith concluded that there was some chemical component, which he called the “transforming factor” in the bodies of the pathogenic bacteria that led to a heritable change in the live nonpathogenic bacteria.

• Nucleic acids transferred from one bacterial strain transformed the other bacterial strain, proving that nucleic acid is the genetic material

Lesson 4: Genetic Mutations

• Chromosomal aberrations

• Changes in the chromosome of organisms that are inheritable and are permanent

• Different types of mutations can result in changes in the quantity or quality of genes or chromosomes, and may or may not affect the phenotype of an organism

Different Type of Genetic Mutations

1. Albinism

• aren’t born with the usual amount of melanin pigment

• Melanin: chemical in your body that determines the color of your skin, hair and eyes. 

• Very pale skin, hair and eyes and prone to sunburn and skin cancer

• Albino: Latin “Albus” means white

• A person with albinism or albinos

• Albinism isn’t a disease. Albinism is a genetic condition that people are born with. It’s not contagious, and it can’t be spread.

• Caused by mutations in specific genes that are responsible for melanin production

• Symptoms of Albinism

• Very pale skin, hair and eyes

• Patches of missing skin pigment

• Crossed eyes (strabismus)

• Rapid eye movements (nystagmus)

• Vision problems

• Light sensitivity (photophobia)

2. Sickle Cell Anemia

• one of a group of inherited disorders known as sickle cell disease

• affects the shape of red blood cells, which carry oxygen to all parts of the body

• some red blood cells are shaped like sickles or crescent moons that become rigid and sticky, which can slow or block blood flow

3. Trisomy 21 (Down Syndrome)

• a person has an extra chromosome (47)

• Babies with Down syndrome have an extra copy of one of these chromosomes, chromosome 21

• Having an extra copy of a chromosome is ‘trisomy.’ Down syndrome is also referred to as Trisomy 21. 

• This extra copy changes how the baby’s body and brain develop, which can cause both mental and physical challenges for the baby.

• Facts about Down Syndrome

• Women of all ages have babies with Down syndrome

• People with Down syndrome can expect to live to 60

• People with Down syndrome are not always happy

• People with Down syndrome are at risk of developing health problems

• Most kids with Down syndrome will live a normal life

4. Hemophilia 

• which the blood doesn't clot in the typical way because it doesn't have enough blood-clotting proteins (clotting factors)

• Internal bleeding can damage your organs and tissues and be life-threatening

5. Huntington’s Disease

• causes the progressive breakdown (degeneration) of nerve cells in the brain 

• has a broad impact on a person's functional abilities and usually results in movement, thinking (cognitive) and psychiatric disorders

• often first appear when people are in their 30s or 40s

• Symptoms 

• Muscle problems, such as rigidity or muscle contracture

• Impaired gait, posture and balance

• Difficulty organizing, prioritizing or focusing on tasks

• Lack of awareness of one's own behaviors and abilities

• Slowness in processing thoughts or ''finding'' words

• Frequent thoughts of death, dying or suicide

6. Cystic Fibrosis

• genetic (inherited) disease that causes sticky, thick mucus to build up in organs, including the lungs and the pancreas

• thick mucus clogs the airways and makes it difficult to breathe

7. Klinefelter’s Syndrome 

• occurs in men as a result of an extra X chromosome

• The most common symptom is infertility

• Klinefelter syndrome is the result of one extra X (written as XXY) 

• Most men with Klinefelter syndrome produce little or no sperm

• It affects testicular growth, resulting in smaller than normal testicles, which can lead to lower production of testosterone. The syndrome may also cause reduced muscle mass, reduced body and facial hair, and enlarged breast tissue.

8. Turner’s Syndrome

• It is found only in girls that can cause problems ranging from short height to heart defects

• partial or complete loss (monosomy) of one of the second sex chromosomes

• XO

• Common symptoms include short stature and premature ovarian failure, which can result in the failure to attain puberty. Most women with Turner syndrome are infertile.

• abnormalities of the eyes and ears, skeletal malformations, heart anomalies, and kidney abnormalities

Based on Chromosome Structure

1. Deletion

• A part of a chromosome is missing or "deleted”

• When genes are missing, there may be errors in the development of a baby, since some of the "instructions" are missing

• One example of a genetic syndrome caused by a deletion is called "Cri du Chat," where part of the #5 chromosome is missing or deleted

2. Duplication

• Part of a chromosome is abnormally copied (duplicated)

• Results in extra copies of genetic material from the duplicated segment

3. Inversion

• A chromosome breaks in two places; the resulting piece of DNA is reversed and re-inserted into the chromosome

• An inversion that includes the chromosome's constriction point (centromere) is called a pericentric inversion

• An inversion that occurs in the long (q) arm or short (p) arm and does not involve the centromere is called a paracentric inversion

4. Translocation

• A piece of one chromosome breaks off and attaches to another chromosome

• Described as balanced if no genetic material is gained or lost in the cell

• If there is a gain or loss of genetic material, the translocation is described as unbalanced 

Genetic Disorders

1. Tay-Sachs Disease or Hexosaminidase

• rare, neurodegenerative disorder in which deficiency of an enzyme (hexosaminidase A) results in excessive accumulation of certain fats (lipids) known as gangliosides in the brain and nerve cells

• SYMPTOMS: muscle weakness, speech problems, and impaired cognitive and motor functions

2. Phenylketonuria

• PKU

• inherited disorder that increases the levels of a substance called phenylalanine in the blood

• Phenylalanine is a building block of proteins (an amino acid) that is obtained through the diet. It is found in all proteins and in some artificial sweeteners.

• SYMPTOMS: stunted growth, epilepsy, and behavioral problems, skin rashes and a mouse-like body odor

3. Cri-du-chat Syndrome

• (cat's cry) syndrome, also known as 5p- (5p minus) syndrome

• when a piece of chromosome 5 is missing

• high-pitched cry that sounds like that of a cat

• by intellectual disability and delayed development, small head size (microcephaly), low birth weight, and weak muscle tone (hypotonia) in infancy

• Affected individuals also have distinctive facial features, including widely set eyes (hypertelorism), low-set ears, a small jaw, and a rounded face. Some children with cri-du-chat syndrome are born with a heart defect

4. Duchenne Muscular Dystrophy

• progressive muscle degeneration and weakness due to the alterations of a protein called dystrophin that helps keep muscle cells intact

Lesson 1: Theory of Plate Tectonics

• Earth began as a single landmass or supercontinent called Pangaea

• The term Pangaea comes from the Greek words pan which means “all” and gaea which means “Earth”.

• Pangaea literally translates to “all of Earth” or “all lands”

• It was surrounded by a vast sea or super ocean called Panthalassa, which means “all seas”

• Tectonic is a term derived from a Greek word tekton which means “carpenter” or “builder”

• Describe the movement of the lithosphere

• Also called lithospheric plates

• Are massive, irregular slab of solid rocks that envelope the surface of Earth.

Theories of Plate Tectonics

1. Contraction theory

• proposed in the early 20^th century.

• this theory suggested that as the Earth cooled after its formation, its surface contracted and wrinkled, with these wrinkles being the mountain ranges on Earth’s surface

• EDUARD SUESS, an Austrian geologist, made an analogy between the wrinkles on the surface of a dried shrunken fruit and the mountains on the surface of a cooling Earth

2. Continental Drift Theory

• Proposed by Alfred Wegener in his book “The Origins of Continents and Ocean in 1915.

• Explained that about 1, 100 million years ago, there was a super continent named Rodinia, which predated Pangaea

• During the late Triassic period, Pangaea began to break up into a smaller supercontinent called Laurasia and Gondwanaland which move to the northern and southern extreme of the planet

• During the history of Pangaea’s formation, the now known North America smashed into northwestern Africa forming a vast mountain range.

• As Pangaea continued northward and crashed into the ocean floor of Panthalassa, it created a chain of mountain ranges extending from Alaska to Southern South America

• At around 250 mya, Pangea began to break apart forming a valley that is now called Atlantic Ocean

3. Seafloor Spreading Theory

• Proposed by an American geologist Harry Hess in 1960s.

• It says that the seafloors or ocean floors, not the continents move and carry the continents along.

Lesson 2: Mechanism of Plate Movements

• The plate tectonics is regarded as the most important theory ever developed in the field of geology. 

• There are TWO major thoughts that were raised to explain the mechanism of tectonic plates. These thoughts are heat loss and gravity which can be explained using the MANTLE CONVECTION THEORY and the SLAB PULL THEORY.

2 Major Ideas that explains the mechanism of tectonic plates

1. Mantle Convection Theory

• A process where can be transferred from one place to another.

• A method of heat transfer that is usually observed among fluid molecules (gas and liquid).

• Warm less dense material rises

• Cooler more dense material sink

• Fluids expand and become less dense when heated. In effect, the less dense fluid rises away from the heat source.  As it rises, it pulls cool fluid down to replace it.

• As the “pulled” fluid becomes heated, it also rises and pulls down more cool fluid creating a cycle that stop only when the heat is evenly distributed throughout the fluid.

• Arthur Holmes (1929)

• Using Wegener’s observations, Holmes suggested that as the mantle becomes heated, its density decreases and eventually rises up. 

• He added that when the material cools it, it would sink, exhibiting a circling behavior that he describes like a conveyer belt

• According to Holmes, the pressure of the heated magma broke the continents apart forcing the pieces to DRIFT in opposite directions. He further speculated that when the materials sank, continents will be brought back together again.

• Tectonic plates are moved passively by convection currents in Earth’s mantle.

• Mantle rocks near the Earth’s core become extremely hot making them less dense than the cooler mantle rocks in the upper layers. In effect, hot rocks rise and the cooler rocks sink.

• The convection currents push the magma up, forming new crusts and exerting a lateral force on the plate, pushing it apart to create seafloor spreading.

2. Slab Pull Theory

• This theory states that gravity and the plates themselves are the ones responsible for the plate tectonics through SUBDUCTION process.

• Subduction zones exist at the outer edges of plates where rocks are older. Hence, they are cooler and denser compared to those located at the inner layers.

• The old rocks or slabs also subduct or sink into the mantle below due to gravitation forces. 

• As the slab is pulled down into the mantle, it drags the rest of the plate along, causing tectonic plate movement. A very dense slab will sink faster than a less dense slab because of the gravitational pull and it will exert greater force on the plate to attached to it.

• The Slab Pull Theory believes that mantle convection is not the cause of plate tectonics but rather, it is a product of subduction.

Lesson 3: Plate Boundaries

• Region between plates

• Plates may move toward each other (converge), move apart(diverge), or move past one another

Types of Plate Boundaries

1. Divergent Plate Boundary

• When two plates move away from each other, a gap or rift between them is created.  If the gap eventually widens, it then evolves into a rift valley. 

• Divergent boundaries between oceanic plates produce mid-oceanic ranges, the mountain ranges formed underwater.

• Any continent or landmass above a divergent plate boundary will be torn apart into distinct landmasses. Surrounding waters will fill the space between them and later become an ocean.

2. Convergent Plate Boundary

• Occur when two plates slide toward each other and form either a subduction zone (if one plate moves underneath the other) or an orogenic belt (if the two simply collide and compress)

• Orogenic belt – region of deformed rocks

• 3 Kinds of Convergence

1. Oceanic-oceanic

• Marina Trench

• When two oceanic plate collides, a subduction zone is formed

2. Oceanic-continental

• In an oceanic-continental subduction, the oceanic plate goes down. As the denser oceanic plate subducts beneath the continental plate and descends into the mantle, the temperature increases, causing the rocks to melt and form magma.

• Andes Mountain of South America

3. Continental-continental 

• When two continental plates collide, no subduction happens. Instead, the continents suture themselves. The continental crust buckles and rocks pile up, creating mountain ranges.

• Alps Mountain Range

3. Transform Plate Boundary

• The plates slide against one another in opposite directions. No mountains or volcanoes are produced. Instead, earthquakes result from the movement of plates and release massive amounts of energy. 

• Earthquakes- refers to the shaking of Earth as a result of the breaking or shifting of the rocks of the tectonic plates.

• Dip slip – movement of faults

• Faults – crack on the Earth’s crust

1. Normal – hanging wall goes down

2. Reverse – hanging wall goes up

3. Strike-slip – slides 

QUARTER 1.2

Lesson 3: Earthquakes

• The Philippines is a large archipelago consisting of more than 7100 islands. 

• It is located along the Western Pacific Basin and lies between two tectonic plates whose interactions give rise to geologic processes like tectonic earthquakes, volcanism, and mass movement. 

• For example, the earthquake in Bohol in 2013, the landslide in 2006 and volcanic eruption of mount Pinatubo 1991 brought about numerous deaths, destruction of properties, dislocation of people, and irreparable damage to environment. 

Earthquakes

• Earthquake - natural phenomenon that is characterized by a sudden, violent shifting of massive plates underneath Earth’s surface. This movement of plates releases stress that generates along geologic faults. 

• Hypocenter (focus) - place beneath the surface from which an earthquake initiated

• Epicenter - Directly above the focus

• Fault - crack across which the rocks have been offset first

• Foreshocks - small earthquakes that commonly precede a major earthquake

• Aftershock - After a major earthquake, smaller earthquakes occur

• Seismograph - instrument used to study earthquake which records the shaking of earthquake waves

• Seismogram - records

Types of Earthquakes

1. Tectonic 

• generated by the sudden displacement along faults in the solid and rigid layer of the earth

• happen when the shifting of the earth’s plate is driven by the sudden release of energy within some limited region of the rocks of Earth

2. Volcanic

• occurs in volcanic regions and can serve as an early warning of volcanic eruptions

• caused by either the injection or withdrawal of magma in response to the changes in pressure in the rock where the magma has experienced stress

3. Collapsed

• caused by seismic waves produced from the explosion of rock on the surface

• It is small earthquakes located underground and in mines that are caused by the integrations of the roof of the mine or cavern or by massive land sliding

3 Types of Faults

1. Normal

2. Reverse

3. Strike slip

Hazards brought by earthquakes

1. Ground breaking - cause mild or severe damage to properties or structures

2. Ground subsidence 

• grounds sink due to earthquake

• Subsidence: lowering of land due to various causes

• Any structure where this event happens can be swallowed. In another instance, a gaping hole can be left

3. Liquefaction

• strength and hardness of the soil are reduced

• the groundwater mixed with ground soil that makes the soil less stable

4. Fault Creep - Slow, more or less continuous movement occurring on faults due to ongoing tectonic deformation

5. Lateral Spread or flow - landslides that commonly form on gentle slopes and that have rapid fluid-like flow movement

6. Tsunami

• Japanese word for tidal wave or big wave in the port

• Coined by fishermen who turned to their ports after their villages had been devastated by a giant wave while the fishermen had not seen any waves in the open sea

• Generated when the ocean floor abruptly deforms and vertically displaces the overlaying water

• The height and strength of the waves depend on the duration and intensity of ground movement under the water

• Causes of Tsunami

1. Underwater earthquakes due to the crustal movements

2. Underwater volcanic eruptions

3. Landslide triggered by falling rocks, corals, or ice

4. Underwater explosions that may either be chemical or nuclear in nature

7. Seiches - large wave that moves up and down instead of forward

8. Landslides - the movement of rock, earth, or debris down a sloped section of land

QUARTER 2.1

Lesson 4: The Electromagnetic Spectrum

• James Clerk Maxwell (1862)

• Predicted the existence of EMW. 

• “Father of EM Theory”

• It was successfully proven by German Physicist HEINRICH HERTZ After Maxwell death

• Our Sun is a source of energy across the full spectrum, and its electromagnetic radiation bombards our atmosphere constantly.

• Earth's atmosphere protects us from exposure to a range of higher energy waves that can be harmful to life

• EM Spectrum: range of all types of EM radiation

• Radiation: energy that travels and spreads

• 2 types of electromagnetic radiation

• the visible light that comes from a lamp in your house

• the radio waves that come from a radio station

7 Types of Electromagnetic Waves

1. Radio wave

• lower frequencies than microwaves

• Radio-wave communications signals travel through the air in a straight line, reflect off of clouds or layers of the ionosphere, or are relayed by satellites in space

• radio captures radio waves emitted by radio stations, bringing your favorite tunes. Radio waves are also emitted by stars and gases in space

2. Microwave 

• extremely high frequency radio waves, and are made by various types of transmitters

• short wavelengths: 1 mm to 30 cm

• Microwaves cause water and fat molecules to vibrate, which makes the substances hot. So, we can use microwaves to cook many types of food.

• Mobile phones use microwaves, as they can be generated by a small antenna. (WIFI)

• fixed traffic, speed cameras, and for radar, which determine the range, altitude, direction, or speed of both moving and fixed objects, such as aircraft, ships, spacecraft, missiles, motor vehicles, and weather formations.

3. Infrared wave

• Infrared light

• human eye cannot see it, but humans can detect it as heat

• infrared absorbed by your skin causes the amplitude of vibration of molecules in your skin to increase. Your skin is warmed.

• Heat or thermal radiation

• A remote control uses light waves just beyond the visible spectrum of light-infrared light waves- to change channels on your TV

4. Visible light

• human eye can view

• human eye can detect wavelengths from 380 to 700 nanometers

• Fireflies, light bulbs, and stars

• It starts with red light and ends with violet light

5. Ultraviolet Radiation

• extending from the violet, or short-wavelength, end of the visible light range to the X-ray region

• emitted by the Sun and are the reason skin tans and burns

• hot objects in space

• undetectable by the human eye

• when it falls on certain materials, it may cause them to fluoresce—i.e., emit electromagnetic radiation of lower energy, such as visible light

• Many insects, however, are able to see ultraviolet radiation

6. X-ray

• see through a person's skin and reveal images of the bones beneath it

• imaging teensy biological cells and structural components of materials like cement to killing cancer cells

7. Gamma ray

• produced in the disintegration of radioactive atomic nuclei and in the decay of certain subatomic particles

• area of oncology to treat malignant and cancerous tumors during a process called gamma knife surgery

• beams of gamma rays are directed at tumors in order to kill cancerous cells

• imaging techniques in nuclear medicine for diagnostic purposes (gamma cameras)

• positron emission tomography (PET) scan: an imaging test that allows your doctor to check for diseases in your body

Lesson 5: Effects of Electromagnetic radiation

• Information is sent from place to place by means of radio waves. 

• We forecast weather using microwaves. Waves even invade our kitchen when food is cooked in a microwave oven. 

• X-rays and gamma rays are now used in medical diagnosis and treatment. 

• Ultraviolet rays are used as a medical sterilizing agent. 

• The hazards brought about by EM waves depend on their FREQUENCY

• The higher the frequency, the greater the energy of the radiation

Electromagnetic Radiation and Life

• Radiation may be ionizing or non-ionizing

• Ionization: process of removing electrons from neutral atoms

• lonizing radiation can produce molecular changes that can lead to damage in biological tissues

• Electromagnetic radiation

1. Ionizing radiation

• X ray and gamma ray

• Immediate effect: death or radiation burns

• Delayed effect: cancer or mutation, which may be on the person exposed to radiation or to his/her offspring

2. Non-ionizing radiation

• Less dangerous

• Radio wave, microwave, infrared light, visible light, UV ray

1. Microwaves cause cataracts

2. Far infrared waves are thermal

3. Shorter, near infrared waves are not hot at all - in fact you cannot even feel them.

4. Excessive exposure to visible light, especially in the blue region, can cause eye damage

5. Lasers can cause blindness

6. Too much exposure to ultraviolet rays burns our skin and produces the so-called sun tan

7. UV rays can also cause skin cancer.

8. Ultraviolet rays can damage the retina

Electromagnetic Radiation and the Environment

• Greenhouse effect: gases in Earth's atmosphere trap the Sun's heat

• Enhanced effect: The greenhouse effect resulting from the increased concentration of greenhouse gases of human activity

• Anthropogenic greenhouse effect

• Enhanced greenhouse effect leads to global warming

QUARTER 2.2

Lesson 6: Reflection

• Light - electromagnetic radiation that has properties of waves and particles

• Image formation by mirrors, the twinkling of stars, the beautiful colors of a rainbow, bending of light by a medium

• Echo – reflected sound wave

• Reflection - when light bounces off an object

• If the surface is smooth and shiny, like glass, water or polished metal, the light will reflect at the same angle as it hit the surface.

• Example of invisible light reflection: surface of a smooth pool of water, where incident light is reflected in an orderly manner to produce a clear image of the scenery surrounding the pool\

• Two types of Reflection

1. Regular or Specular: reflection from smooth surfaces

2. Diffuse: rough surfaces

• Incident light ray (incoming light wave) - which lands upon the surface is said to be reflected off the surface

• Reflected ray – the ray that bounces back

• Normal - a perpendicular drawn on a reflecting surface

• The law of reflection: determine the reflection of incident light rays on reflecting surfaces

1. The incident ray, the reflected ray and the normal all lie in the same plane

2. The angle of incidence = Angle of reflection

Mirrors and Reflection of Light

2 types of Mirrors

1. Plane Mirror

• Flat surface

• Ordinary mirror

2. Spherical Mirror

• Example: shiny spoon

• Concave or convex

1. Concave

• Inside curve of a spoon

• Can produce real or virtual images, depending on the distance between the mirror and the object

• The image may be larger, the same size as, or smaller than the object

2. Convex

• Curve outwards, like the back side of the spoon 

• The image formed is never real because the reflected rays spread out from the mirror

• Images formed by a convex mirror are always virtual, upright, and smaller than the object.

Uses of Concave and Conex

1. Concave Mirror

• used in certain types of astronomical telescopes called reflecting telescopes

• The mirrors condense lots of light from faint sources in space onto a much smaller viewing area and allow the viewer to see far away objects and events in space that would be invisible to the naked eye

• Concave lenses are used in eyeglasses for people who are nearsighted (those who have trouble seeing things that are far away)

2. Convex Mirror

• shop security and rear-view mirrors on vehicles because they give a wider field of vision

• Convex lenses are used in glasses for people who are farsighted (those who can’t see things very well up close)

Lesson 7: Refraction

• This bending by refraction makes it possible for us to have lenses, magnifying glasses, prisms and rainbows.

• Without refraction, we wouldn’t be able to focus light onto our retina.

• Retina - part of the eye that receives light and send these signals on to the brain for visual recognition

• Refraction - bending of light as it passes from one medium to another

• Since the surface of the glass is curved, the water in the glass also acts as a magnifying glass, slightly enlarging the spoon

• Cause of refraction: Change of Speed Results in Change in Direction

• Light refracts whenever it travels at an angle into a substance with a different refractive index (optical density)

• When light travels from air into water, it slows down, causing it to continue to travel at a different angle or direction

Refractive Index

• Index of Refraction

• Describes how fast light travels through the material 

• Dimensionless

• Refractive index (n) =  Speed of light in vacuum (c)

        Speed of light in the medium (v)

• N = c/v

• C = 3x10⁸ m/s

• N₁ of air = 1.0003

Laws of Refraction

1. The incident ray, refracted ray, and the normal to the interface of two media at the point of incidence all lie on the same plane.

2. (a) When a ray of light passes obliquely from an optically denser medium to a less dense medium, it is refracted away from the normal. 

(b) When a ray of light passes obliquely from an optically less dense medium to a denser medium, it is refracted towards the normal. 

(c) When the incident ray is perpendicular to the interface, no bending of light ray occurs. 

3. Snell’s law, named after the Dutch astronomer and mathematician Willerbrord Snell, relates the index of refraction of two media and the angles from the normal using the equation:

n1 sinθ1=n2 sinθ2

n1= index of refraction of the incident medium

n2=index of refraction of the refractive medium

1= angle of incidence

2= angle of refraction

Shallowing Effect

• Effect of refraction

• Objects submerged in a liquid always appear to be shallower than they actually are

• The light coming from the objects changes angle at the surface of liquid, bending towards the liquid. It can be shown mathematically that the index of refraction is the ratio of the real depth to the apparent depth.

• N =   Real depth

     Apparent depth

• N of water = 1.33

Refraction of Light in Real Life

• Result of Refraction: Mirage and looming optical illusions

• A swimming pool always looks shallower than it really is because the light coming from the bottom of the pool bends at the surface due to refraction of light.

• Formation of a rainbow is an example of refraction as the sun rays bend through the raindrops resulting in the rainbow.

• When white light passes through a prism it is split into its component colors – red, orange, yellow, green, blue and violet due to refraction of light.    

QUARTER 3.2

Lesson 8: Endocrine System

• Hormones: partially control or regulate the fast reactions and slow changes happening in your body

• Happiness Chemicals

1. Dopamine – Reward Chemical

2. Oxytocin – The Love Hormone

3. Serotonin – The Mood Stabilizer

4. Endorphin – The Pain Killer

• Hormones: chemical messengers that carry instructions to cells to change their activities

• Gland: organ whose cells secrete materials to the different parts of the body

• Endocrine Gland

• Endo means “within”, krinein means “separate”

• ductless glands that secrete hormones directly into either the bloodstream or the fluid around the cells

• brain, stomach, small intestine, kidney, liver, and heart

Endocrine System

• These hormones control nearly all the processes in your body

• body’s functions, from metabolism to growth and development, emotions, mood, sexual function and even sleep

• Hormones deliver their messages by locking into the cells they are targeting so they can relay the message

• Your endocrine system continuously monitors the amounts of hormones in your blood

• Homeostasis: self-regulating process by which an organism tends to maintain stability while adjusting to conditions that are best for its survival

• Endocrine system is made up of organs called glands

• Glands produce and release different hormones

• Hormones nearly affect every process in your body

1. Metabolism

2. Growth and development.

3. Emotions and mood.

4. Fertility and sexual function.

5. Sleep.

6. Blood pressure

Major Endocrine Glands

• Hypothalamus

• At the base of the brain

• Link between the nervous system and the endocrine system

• Determine when to tell other glands, including the pituitary gland, to produce hormones

• Pituitary Gland

• Hypophysis

• in the center of the skull

• Referred to as the “master gland” because it produces hormones that control many activities of the other endocrine glands

• made of two lobes, the anterior and posterior glands

• Thyroid Gland

• under the larynx or voice box

• three hormones: triiodothyronine (T₃), thyroxine (T₄), and calcitonin

• Both T₃ and T₄ contain the element iodine

• maintaining heart rate, blood pressure, muscle tone, and reproductive functions

• An insufficient amount of these hormones in the body can lead to hypothyroidism, which causes weight gain, lethargy, and intolerance to cold

• Parathyroid Glands

• These four tiny glands control the level of calcium in your body

• release the parathyroid hormone

• Adrenals

• The word adrenal means “above kidney”

• located at top each of your kidneys

• inner adrenal medulla and the outer adrenal cortex

• inner adrenal medulla

• produces adrenaline which plays an important role in the body’s coping mechanism

• part of the body’s emergency action team

• gives the body a strength that could be considered “superhuman”

• Pineal Gland

• located near the thalamus of the brain

• produces melatonin (a hormone that causes you to feel sleepy)

• synchronizes daily rhythms, regulates body systems, and helps the body adapt to seasonal changes

• Pancreas

• produces two types of hormones: insulin and glucagon

• Insulin: keeps the levels of sugar (glucose) in the bloodstream under control

• Glucagon: increases the level of sugar in the body by speeding up the conversion of glycogen into sugar in the liver

• Ovaries 

• ovaries release sex hormones called estrogen, progesterone

• Testes

• make sperm and release the hormone testosterone

Conditions and Disorders affect Endocrine System

1. Diabetes

• chronic (long-lasting) health condition that affects how your body turns food into energy

• Most of the food you eat is broken down into sugar (also called glucose) and released into your bloodstream. When your blood sugar goes up, it signals your pancreas to release insulin. 

• Glucose meter/ Glucometer

• 3 types of Diabetes

1. Type 1 diabetes: need to take insulin injection for lifetime 

2. Type 2 diabetes

• Insulin Resistance: The body produces minimal insulin or the body’s cell do not react to insulin, a condition

• 90% of diabetes cases

• Diet exercise, and taking antidiabetic tablets

3. Gestational diabetes

• Due to hormonal changes during pregnancy, a pregnant woman’s cell is less responsive to insulin

• As more glucose enter the placenta and is absorbed by the baby, it can lead to condition known as macrosomia or “fat baby”

2. Thyroid Disorders

• Hypothyroidism happens when the thyroid doesn’t produce enough hormones

• Hyperthyroidism occurs when it creates too many hormones.

3. Hypogonadism

• Low Testosterone

• In men, hypogonadism can cause erectile dysfunction

• testes do not produce enough of the sex hormone testosterone

4. Polycystic Ovary Syndrome (PCOS)

• irregular periods, abnormal hair growth, excess acne and weight gain

• The ovaries may develop numerous small collections of fluid (follicles) and fail to regularly release eggs.

• Having PCOS does not mean you can't get pregnant. PCOS is one of the most common, but treatable, causes of infertility in women.

5. Osteoporosis

• When a woman’s ovaries don’t produce enough estrogen, bones become brittle and weak

• People with an overactive parathyroid gland (hyperparathyroidism) may also have weak bones.

6. Dwarfism

• Pituitary dwarfism: body’s insufficient production of growth hormones

• Dwarfism is short stature that results from a genetic or medical condition

• Some people prefer the term "short stature" or "little people" rather than "dwarf" or "dwarfism."

• Disproportionate Dwarfism and Proportionate Dwarfism

QUARTER 4.2

Lesson 9: Genetic Manipulation

• Biotechnology: coined from the words biology and technology in the 1970’s, when the first genetically engineered bacteria were reported. 

• use of biological processes of microorganisms

• Hybridization: merges the best traits of different organisms

• Inbreeding: maintain the continuous transmission of desired characters along the genetic line

• Recombinant DNA: a form of genetic engineering that allows gene from one organism to be transferred into the DNA of another organism.

• Molecular biologists, must use their knowledge of the DNA structure and its functions to manipulate the DNA molecules including…

1. extracting the DNA from cells 

2. cutting them to smaller segments

3. identifying the sequence responsible for the trait

4. making unlimited copies 

5. Bringing them together with a different segment forming a hybrid 

Biotechnology in your food

• Improvement of crop quality and yield has been the major goal of farmers since people started to cultivate plants. 

• Scientists have explored various ways of genetic modification to give food crops desirable characteristics such as….

• Resistance to insecticides and drought

• Improve taste, texture, size, and color of fruits and vegetables

• Improve protein content in grain crops

• Genetically modified food: crops created for human or animal consumption by employing the latest genetic engineering methodologies

• Falvr savr tomato: first genetically engineered crop product to be commercialized (to be left longer to ripen on the vine)

• Scientists cut the male flower at the stem and rub the pollen-producing section against the female flower. When pollinated, it creates a watermelon, which contains the seeds of the seedless variety.

• Cantaloupes, Potatoes, Corn - resistance to insects and other pest

Lesson 10: Evolution

• Satanic leaf-tailed gecko

• 3 Observations by Wildlife Biologist

1. Organism are well suited to the environment where they live

2. Although it appears to be different, it shares a lot of similar common characteristics with other life forms

3. It offers a glimpse of life’s rich biodiversity

• Evolution: refer to any change in the genetic composition of a population of organisms over time

• Writings of plato

• Georges-Louis Leclerc Comte de Buffon

• In the eighteenth century, ideas about the evolution of animals were reintroduced 

Theoretical Ideas about Evolution

1. Lamarck’s Theory of Adaptation

• Around 1800, some scientists started to question whether living organisms could really change their structure or form

• French scientist Jean Baptiste de Lamarck suggested the concept of inheritance of acquired characteristics.

• The development of long necks in giraffes

• He said that change is made by what the organisms want or need –LAW OF USE AND DISUSE

• For example, Lamarck believed that elephants all used to have short trunks. They stretched their trunks to reach the water and branches, and their offspring inherited long trunks. 

• Lamarck also said that body parts that are not being used, such as the human appendix and little toes are gradually disappearing. Eventually, people will be born without these parts

• He proposed that if an animal could develop a particular characteristic in its lifetime, then this trait could be passed on to their offspring and its succeeding generations

2. Charles Darwin and Natural Selection

• middle of 19^th century when Charles Darwin (1809-1882), an English naturalist and geologist, developed his theory about evolution.

• During his expedition, he witnessed the diversity of life forms including some fossils records

• Darwin had read Malthus’ essay about human population growth

• “Survival of the fittest”

• Herbert Spencer

• (1820–1903) was an English philosopher who initiated a philosophy called 'Social Darwinism'.

• He coined the term 'survival of the fittest' seven years before Darwin's publication of his theory of natural history, The Origin of the Species in 1859.

• Social Darwinism: Successful deserve their success while those who fail deserve their failure

• Natural Selection: if an organism developed and possessed a small inherited variation that would increase the individual’s ability to compete, survive, and reproduce, then this characteristic will be passed on

• He published this idea in his Origin of Species by Means of Natural Selection

• James Hutton

• published his hypothesis that layers of rock can form slowly and move forces beneath Earth’s surface. Other rock layers are buried and then pushed upward from the seafloor, which gave rise to mountains and valleys that are further shaped by rain, wind, and temperature

• Charles Lyell

• made an argument that the laws of nature in the form of geological processes are constant and assumed that the geological activities that are occurring today must have also happened in the past, which shaped Earth millions of years ago. 

3. Mendel’s Key to the Missing Link

• An Austrian Monk named Gregor Mendel (1822-1884) was carrying out imperative experiments that would finally prove Darwin’s concept of natural selection

• He was able to cultivate almost thirty thousand pea plants and in doing so, figured out the basic foundation of genetics

• Using Mendel’s work on genetics, a couple of studies showed how genetic traits in an animal or plant population could be selected by environmental pressure and how these populations easily become adapted to its environment

• The genetic makeup of an organism is known as genotype

• The organism’s genotype (nature) and the environment I which it lives (nurture) regulate the characteristic traits of the organism called phenotype

1. Mutations

• change in a DNA sequence

• common fruit fly

• (Drosophila melanogaster); a single mutation in the fruit fly can alter its eye color from normal red to white

2. Gene Flow

• A result of migrating individuals that breed in a new location is called gene flow

• pollen or spores being dispersed by air in a new location, animals hibernating and transferring to anew locale due to changes in temperature, or humans moving to new cities or countries

3. Genetic Drift

• Any change in the allele frequencies in a population due to random sampling is called genetic drift

• The bottleneck effect is an extreme example of genetic drift that happens when the size of a population is severely reduced.

4. Founder Effect

• a small group of individuals breaks off from a larger population to establish a colony