3RD QTR: EARTH AND LIFE SCIENCE

ORGAN SYSTEMS

• group of organs

• work together to perform a certain function in an organism’s body

• are INTERDEPENDENT, interconnected, and packaged together in a relatively small space

  • independent in terms of its functionality, but are interdependent

NUTRITION

Activities by which living things obtain raw materials from the environment (transport them into cells)

NUTRIENTS

Chemical substances that organisms need to grow and function properly

ORGANIC

Carbon-based

AUTOTROPHS

Create their own food

DIGESTION

Breakdown of organic compounds into their simple forms for use by the cells

• digestive system breaks down food in 2 ways:

  • mechanically: movement of the body 

  • chemically: acids, liver releasing bile, pancreatic juices

PARTS OF DIGESTION

1. Mouth

2. Esophagus

3. Stomach

4. Small Intestine

5. Large Intestine

• often overlooked

• final state of food goes through here before the rectum

• absorbs remaining water in the body

6. Liver

• releases bile

7. Pancreas

• makes enzymes to digest the food further

8. Gallbladder

• holds bile

AIR

Made up of oxygen, nitrogen, carbon dioxide, and other gases

BREATHING

• mechanical process of pumping air into and out of the lungs

• done by a group of organs that make up the respiratory system

• exchange oxygen and carbon dioxide between air and the cells

• involves lungs only

• inspiration and expiration

RESPIRTATION

• process of exchange of oxygen and carbon dioxide between organism and its environment

• involves RBC and lungs

• 2 major processes of respiration:

  • internal respiration

  • external respiration

GILLS

• used by fish and other marine species to absorb oxygen trapped in water 

• filters carbon dioxide out of the bloodstream

• water does not go through stomach, only passes through the gills

  • absorbs trapped oxygen in the water

  • cannot breathe on land because they cannot collect oxygen

TRACHEAL SYSTEM

• insects, few land arachnids, and myriapods

• an elaborate system of small, branching tubes that carry oxygen to individual body cells

• trachea is from its head to butt

  • air sacs are spread out through their body

AMPHIBIANS

• amphibians, earthworms, some turtles

• respire through a process called cutaneous respiration

  • form of respiration in which gas exchange occurs across the skin

• breathe passively for their skin to absorb the air

  • take in oxygen and release carbon dioxide

• mechanisms are like this so they can absorb the oxygen in the soil as they are usually underground

• they eat through a small opening in their mouth to suck juices from decaying matter

CIRCULATORY SYSTEM

• road network within the body

• life support that feeds our cells with food, nutrients, oxygen, and removal of waste products

• 3 main parts: heart, blood vessels, blood

HUMAN HEART

• located between lungs in the middle of chest

• living pump

• each side is divided into 2 chambers:

  • atrium – accepts deoxygenated blood

  • ventricle – oxygenated blood

BLOOD VESSELS

• form an intricate transportation network to service every cell

• 3 kidneys of blood vessels:

  • arteries – away from heart (oxygenated)

  • veins – towards heart (deoxygenated)

  • capillaries – connects arteries to veins

• the blood vessels near the organs get thinner to better penetrate through them

BLOOD

• brings oxygen and nutrients to all parts of the body so they can keep working

• made up of 2 components:

  • blood plasma — majority of the blood; helps achieve the liquid consistency

  • formed elements

URINARY SYSTEM

• made up of organs that rid of the liquid waste in body

• kidney is one of the most important organs of the urinary system

• filters metabolic wastes: water, salts, and urea

IMMUNE SYSTEM

• made up of specialized cells, proteins, tissues, and organs

• protects and defends us against germs and pathogenic microorganisms

• major job: keep people healthy and prevent infections

• immune system is divided into 2:

  • innate immunity – built-in (ex: WBC, skin)

  • adaptive – specific (ex: Dengue, COVID, chickenpox)

LYMPH NODES

filter lymphatic fluid and store special cells that can trap cancer cells or bacteria

THYMUS

Site of maturity of T-cells that function for adaptive immune response

SPLEEN

Contains white blood cells that fight infection or diseases

BONE MARROW

• Lymphoid organ

• involved in the production of leukocytes, mainly the T-cells and B–cells

  • leukocytes – work in coordinated manner to monitor body for germs

  • eat the pathogens (phagocytosis)

NERVOUS SYSTEM

• made up of brain, spinal cord, and nerves

• controls much of what you think and feel and what your body does

  • Central Nervous System and Peripheral Nervous System

BRAIN

Main control center of coordination

CEREBRUM

Intelligence

Cerebellum

Coordination / Balance

Medulla

Controls and coordinates the activities of internal organs

SPINAL CORD

• organ made up of tightly packed neurons

• carries nerve impulses from all over the body to and from the brain

  • ex: heartbeat

• controls many of the body’s involuntary actions

NERVE CELLS

• Information and signal processors of the body

• a human being has approximately 100 billion neurons

• neurons vary in size and shape

  • but have a common structure (dendrites-axons)

  • stellate shape that allows information to spread rapidly

• nerve fillings are important for telling the brain not to do something

SKELETAL SYSTEM

• delivers form and support to the body

• bone serves to the following

  • protect the vital organs inside the body

  • protect and supports muscles

  • produce blood cells

• includes bones, cartilage ligaments, and tendons

BONE

Hard, living tissue, contains blood vessels, nerves, and dividing cells

CARTILAGE

Softens the ends of the long bones where they meet

PLANT ANATOMY

• deals with structure

• in-depth detailed examination in order to identify position, relations, structure, and function of body parts

PLANT MORPHOLOGY

• study of the physical form and external structure of plants

• general term for the study of the morphology of plants

  • physical form and external structure

ROOT SYSTEM

• below the ground, not visible

• composed of root

• responsible for absorbing different nutrients of the ground

ANATOMY OF ROOT SYSTEM

• almost always underground

• main goal is to absorb nutrients

• pointy structure to penetrate the soul

  • where all essential nutrients are

• primary root cannot be destroyed

  • all branches go through here for them to go to the shoot system

  • main function is for increased surface area

• lateral root grows sideways to get more nutrients

CADMIUM BABY CELLS

Branches out if plant needs more lateral stem

APICAL MERISTEM

Stimulates lateral growth

XYLEM

Water passes

PHLOEM

Nutrients pass to deliver to other parts

SHOOT SYSTEM

• exposed to atmosphere, above ground

• composed of stem, leaves, flowers, and fruits

• more complex

ANATOMY OF LEAF

• usually a green, flattened, lateral structure attached to a stem

• functions as a principal organ of photosynthesis

• part where gas exchange (CO2-O2) occur

• plant mostly likes the colors red and blue — reason for its green color

ANATOMY OF FLOWER

• present in angiosperms only

• possess whorls of often colorful petals or sepals

• bears the reproductive parts

• androgynous – both male and female parts

• stigma receives pollen → goes down to female parts

• bees are known to be the best pollinators

ANATOMY OF SEED

• mature ovule of a flowering plant

• considered as the embryo, which bears the young plant

• micropyle is a small pore that allows water absorption, which can trigger germination.

ANATOMY OF FRUIT

• mesocarp – part we eat

• seed-bearing structure of a plant which is formed from the ovary

ADVENTITIOUS ROOTS

• Rise aboveground to get more nutrients → spread over large areas

METABOLISM

• all things that keep you alive can be converted into energy

  • ex: oxygen, heart, food, brain, medicine, sun, water, etc.

• Law of Conservation of Energy: “Energy cannot be created nor destroyed”

• living things are actively engaged in energy transformations

• only Earth has the capacity to harness energy from other sources and transform this for life

• Metabolism is the sum of all chemical reactions in the cell

• Cells are chemical factories

NUTRITIONAL DIVERSITY OF ORGANISMS

• Carbon Requirements

  • CO2 or organic compounds

• Energy sources

  • light or chemical

• Oxygen Requirements for ATP Synthesis

  • aerobic or anaerobic

CATABOLISM

• Complex molecules are broken into smaller and simpler molecules

• Example: Cellular Respiration

  • glucose is broken down into CO2 + H20, releasing ATP

ANABOLISM

• Simpler molecules are used to build complex and larger molecules

• Example: Photosynthesis

  • CO2 + water is converted into glucose and oxygen

ATP (ADENOSINE TRIPHOSPHATE)

• Cells require ATP for all activities

  • including movement and metabolism

  • without ATP, the body weakens

• ATP is obtained from food

• the cell “pays” with ATP to perform functions

PROTEINS

• proteins are essential macromolecules synthesized by cells

• proteins are the functional language of the cells

• during metabolism, complex proteins are created 

  • which helps maximize ATP production

• DNA to RNA to Protein process:

  • DNA is converted into RNA to exit the nucleus

  • RNA interacts with ribosomes, where it is translated into protein

  • Amino acids form chains, resulting in proteins

• many proteins, including enzymes, work by binding to other molecules

ENZYMES

• speed up reactions by reducing the energy required

• every reaction in the body requires millions of ATP molecules

  • cells collaborate with enzymes to make reactions efficient and less energy-consuming

• enzymes are shaped to fit a molecule called substrate

  • once the substrate binds to the enzyme’s active site, a chemical reaction occurs

    • either breaks down or builds molecules

TEMPERATURE

• high temp. – will not work properly

• many temperature-sensitive proteins have been discovered in a wide variety of organisms

PH LEVELS

• example in the digestive system:

  • Pepsin (stomach enzyme) functions in an acidic environment

  • Trypsin (intestinal enzyme) functions in a basic environment

ENZYME INHIBITORS

• some molecules bind to enzymes, slowing down or stopping their activity

• Reversible inhibitors bind noncovalently

  • meaning their effects are temporary

PHOTOSYNTHESIS

• photoautotrophs use light energy to drive the synthesis of organic molecules for carbon dioxide and water

• water and carbon dioxide are converted into glucose and oxygen

• the process of photosynthesis & aerobic respiration are interconnected:

  • animals produce carbon dioxide, which plants use

  • plants produce oxygen and food, which animals consume

PROCESS OF PHOTOSYNTHESIS

• Photosynthesis primarily occurs in the leaves of plants

• Chloroplasts are organelles responsible for photosynthesis 

• Inside chloroplasts are thylakoids, which are stacked into grana

  • Chlorophyll, the green pigment inside the thylakoid, absorbs light to drive the action

  • Photosynthesis occurs in the thylakoid membranes

LIGHT-DEPENDENT REACTIONS

• occurs in the thylakoid membrane

• converts light energy into chemical energy in the form of NADP and ATP

• uses the visible light spectrum:

  • plants absorb mostly blue and red photons

  • green light is reflected, which is why plants appear green

• light excites chlorophyll →  triggers electron movement → powers synthesis of ATP and NADPH

LIGHT-INDEPENDENT REACTIONS (CALVIN CYCLE)

• occurs in the stroma

• uses ATP and NADPH from the light-dependent reactions to convert CO2 to glucose

• Carbon Fixation

  • the first step of the Calvin Cycle

  • CO2 is attached to another molecule using the enzyme, RuBisCo

  • once attached, this initiates a process that generates glucose

CELLULAR RESPIRATION

• the process of breaking down glucose to release ATP

• takes place in the mitochondria and cytoplasm

GLYCOLYSIS

• occurs in the cytoplasm

• breaks down glucose (C6H12O6) into 2 molecules of pyruvate

• 3 key steps:

  • Energy Investment Phase: 2 ATP are used to activate glucose

  • Glucose Splitting: Glucose (6C) is split into two 3-carbon molecules

  • Energy Payoff Phase: produces 4 ATP (net gain of 2 ATP) and 2 NADH

• End products: 2 Pyruvate, 2 ATP (net), and 2 NADH

KREBS CYCLE

• also the Citric Acid Cycle

• takes place in the mitochondria

  • generates electron carriers

• further breaks down pyruvate to release energy-storing molecules

• Key steps:

  • Pyruvate is converted into Acetyl-CoA

  • Acetyl-CoA enters the cycle, combining with a 4-carbon molecule

  • series of reactions release CO2, NADH, FADH2, and ATP

  • End Products: 6CO2, 2 ATP, 8 NADH, 2 FADH2

ELECTRON TRANSPORT CHAIN

• where ATP is produced through oxidative phosphorylation

• uses NADH and  FADH2 to generate a large amount of ATP

• Key Steps:

  • NADH and FADH2 donate electrons to the electron transport chain

  • Electrons move through proteins, pumping H+ ions across the membrane

  • H+ ions flow back through ATP Synthase, generating ATP

  • Oxygen acts as the final electron acceptor, forming H2O

• End Products: ~34 ATP and H2O