Science AT4 - 8.1, 8.2
the deoxygenated blood enters the heart through either the superior or inferior vena cava, depending on where it came from. the vena cava are the largest veins in the body. from the vena cava, the blood travels into the right atrium, through the tricuspid valve, into the right ventricle, through the pulmonary valve, into the pulmonary trunk, and out to the lungs via the pulmonary arteries. once in the lungs, the deoxygenated blood picks up oxygen from alveoli by diffusion and becomes oxygenated. then it returns to the heart via the pulmonary veins, into the left atrium, through the mitral valve, into the left ventricle, through the aortic valve, and into the body via the aorta. the aorta is the largest artery in the human body.
chemically bonded is not the same as chemically combined.
you can have two or more different atoms/molecules chemically bond and
you can have two or more different compounds/elements chemically combine
a chemical change is the result of a chemical reaction, and a chemical equation describes what happened.
change and reaction can be used interchangeably
yip yop
an atom is the smallest whole part of matter
an element is a type of matter made up of one type of atom
a molecule is a type of matter made up of two or more atoms that are chemically bonded together
a mixture is a material consisting of two or more different elements/compounds with no fixed ratio. components are not chemically combined so it can be physically separated
a compound is a type of matter made up of two or more different types of atoms that are chemically bonded together
physical change is where matter changes its physical state as a result of energy charges
chemical change is when one or more substances are changed to produce one or more new substances by breaking existing bonds and creating new ones
an acid is a compound that reacts with metals to produce hydrogen and reacts with an alkali/soluble base to produce a neutral solution consisting of salt and water
a metal is a type of matter that is solid (except for mercury), malleable, ductile, lustrous, sonorous, a good conductor of heat and electricity.
an alloy is a mixture of two or more metallic elements which results in different physical properties.
lustre is the manner in which a newly exposed surface of a metal reflects light
non metals:
hydrogen, helium, carbon, nitrogen, oxygen, fluorine, neon, phosphorous, sulfur, chlorine, argon, bromine,
H He C N O F Ne P S Cl Ar Br
thoracic/chest cavity is the hollow space inside the chest that holds structures such as the lungs, heart, etcc
the bronchi divide from the trachea and each one is connected to a lung. the left bronchus is longer, more narrow, more horizontal. surrounded by irregular rings of cartilage. made of smooth muscle
alveoli are balloon shaped structures within the alveolar sacs. hollow cavities. one cell thick for diffusion of dissolved gases. large surface area for maximum diffusion, over 300 million inside the lungs
upper respiratory tract: mouth, nose, nasal cavity, pharynx, larynx,
lower respiratory tract: trachea, bronchi, bronchioles, alveoli, diaphragm, lungs
bronchi are tubes that divide from the trachea, smooth, muscular tubes. surrounded by irregular rings of cartilage, each one connects to a lung. the left bronchus is longer, more narrow, more horizontal.
what is the difference between cellular respiration and breathing?
cellular respiration is the chemical reaction that takes place in the mitochondria of all living things where oxygen reacts with glucose to produce carbon dioxide, water, and energy.
breathing, on the other hand, is the physical inhalation and exhalation of air via the respiratory tract.
e rutherford’s gold foil proved that there were positively charged protons in the nucleus of atoms.
Copper, Iron, Gold, Lead, Silver, Zinc, Mercury, Iodine, Bromine, Tin
M M M M M M M NM NM M
An alloy is a mixture of two or more metallic elements resulting in different physical properties. not a fixed ratio.
electrolysis is the use of electricity to cause a chemical reaction
NM: Hydrogen, Helium, Carbon, Nitrogen, Oxygen, Fluorine, Neon, Phosphorus, Sulfur, Chlorine, Argon, Bromine, Oganesson,
JJ Thomson’s atomic model was the plum pudding model. consisted of a positive matrix with electrons scattered throughout.
Ionic bonds - when atoms that are very different give or swap valence electrons
Bohr’s atomic model was the planetary model, stating that atoms consist of a dense nucleus of protons and neutrons, orbitted by electrons
An element is a type of matter made up of one type of atom. Homogeneous, fixed ratio
Isotopes have a different number of proton and neutron.
Isobars have protons and neutrons = equal.
Petroleum is a liquid mixture of hydrocarbons which can be extracted from rock strata and refined to produce fuels such as petrol, paraffin, diesel.
A compound is a type of matter that is made up of two or more different types of chemically bonded atoms. Homogeneous fixed ratio
Physical changes are easier to reverse than chemical changes as they do not involve the rearrangement of atomic structures
Atoms are arranged in the periodic table according to increasing atomic number, or proton amount in the nucleus of its atoms.
an acid is a compound with a ph lower than 7. reacts with metals to produce hydrogen and reacts with an alkali or soluble base to produce a neutral solution.
carbon dioxide extinguishes a flame
an alkali is a soluble base that neutralises an acid.
nucleon refers collectively to protons and neutrons
daltons atomic model is the billiard ball. hard, discrete, indivisible packets of matter
oxygen promotes burning
protons and neutrons are each approx 1840 times heavier than electrons
hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine, argon, potassium, calcium.
CH4
Valence electron is one on the outer shell that performs bonds
2, 8, 8
opposites attract, like repel neutrons do neither
an ion is an atom that has a positive or negative charge. positive charge means more protons than electrons, negative means more electrons than protons.
positive = cation
rutherford’s atomic model is the nuclear model. consisted of a dense nucleus made up of protons only, orbitted by electrons, no neutrons.
photosynthesis occurs in all plants in the chloroplast. carbon dioxide reacts with water under the presence of sunlight and chlorophyll to produce oxygen and glucose.
mass number is ejejjejeje the mass number refers to the amount of protons and neutrons in the nucleus of an atom, or nucleon. mass number is different to the atomic mass. atomic mass is a decimal, and the mass number is the atomic mass rounded to no decimal places
atomic number is written ehehehehhe it is the number of protons in the nucleus of an atom.
a molecule is a type of matter made up of two or more chemically bonded atoms. these atoms can be the same type or different.
negative ion is called an anion
M: Lithium, Beryllium, Sodium, Magnesium, Aluminium, Potassium, Calcium, Iron, Tin, Gold, Silver, Mercury, Lead, Cobalt, Zinc,
Signs of a chemical reaction:
Permanent change in colour
Disappearance of an original substance (not always)
Appearance of a new substance
Change in temperature
Energy given off
Fizzing/effervescence
Covalent bonds occur between similar atoms (metals or non metals or metalloids etc) where valence electrons of the atoms are shared. 2 8 8 orbittals overlapped
noble gases are gases that do not usually react because they have a full outer ring of electrons. they are very stable
displacement reaction is when element takes the place of another element in a compound
smallest part of a compound that can exist by itself and retain all of its chemical properties is a molecule.
MAtter is anything that has mass and takes up space
cellular respiration is silly
a base has a pH higher than 7 and a soluble one reacts with an acid to produce a neutral solution
combustion occurs when a fuel such as a hydrocarbon reacts with oxygen to produce carbon dioxide, water, and lets off a useful energy such as heat or light.
the smallest unit of an element that can exist alone and retain all of the element’s chemical properties is an atom
neutralisation is a chemical reaction where an acid reacts with a soluble base (alkali) to produce a neutral solution (salt and water)
hydrogen makes a popping noise when it comes in contact with a flame
precipitate is the insoluble solid that settles to the bottom of a solution. a precipitation reaction is when two solutions with soluble compounds combine to form an insoluble precipitate. this will “fall out” of the solution.
bronchi are smooth muscular tubes that divide from the trachea. they are surrounded by irregular rings of cartilage and divide into bronchioles. there are two bronchi, left and right. the left bronchus is narrower, more horizontal, longer than the right. each one is connected to a lung, carries air to and from
lower respiratory tract: trachea, bronchi, bronchioles, alveoli, lungs, diaphragm
upper respiratory tract: nose, nasal cavity, mouth, pharynx, larynx
alveoli are balloon shaped structures within alveolar sacs. hollow cavities. place where the exchange of gases occurs. one cell thick. for quick diffusion. large surface area for efficiency, moist
pharynx is a muscular tube that connects the nose and mouth to the larynx and oesophagus. passageway for air. also referred to as the throat on its own.
nasal or oral cavity, pharynx, larynx (passes epiglottis), trachea, primary bronchi, secondary, tertiary, bronchioles, alveoli, capillaries,
bronchioles divide from the tertiary bronchi and connect to alveolar sacs. they transport air to the alveoli for exchange of gases. less than 1mm in diameter.
elimination: removal of waste material from the digestive tract, such as faeces.
excretion: removal of metabolic wastes produced by cells.
when you breathe in, your diaphragm contracts and pulls downwards. your intercostal muscles, muscles between your ribs, contract, pulling your ribcage up and out. these actions expand the chest cavity so that the lungs can expand into it. the air pressure inside the lungs is reduced; this causes air to naturally flow into the lungs.
alveolis’ surfaces are moist so that gases can be fully dissolve before diffusing as it makes the process more efficient
the diaphragm is a curved broad band of muscle that forms the base of the chest cavity. sep chest cavity from abdomen. controls breathing by contracting and expanding.sits underneath the lungs.
the larynx is also known as the voicebox. it acts as a passageway for air to pass through and sits above the trachea. protects the trachea by producing a coughing reflex if solids pass the epiglottis.
the trachea is a tube that leads from the back of the throat to the bronchi. muscular tube surrounded by c shaped rings of cartilage due to its position in relation to the oesophagus. inner membrane is lined with cillia, microscopic hairs that catch dust particles from air.
when you breathe out, the diaphragm expands back up. the ribcage is pulled back in and out because the intercotal muscles expand. the lungs contract, air pressure in lungs is increased.
throat mainly consists of pharynx + larynx. mostly pharynx. but technically it also contains the epiglottis, oesophagus, tonsils
alveolar sacs are clusters of alveoli
the epiglottis is a small flap of cartilage above the larynx (voicebox). it is usually upright but moves to block the larynx when food enters the body.
the bladder is a storage space that holds urine (wastes that have been filtered from the blood) before it is expelled from the body.
the ureter is the tube that carries wastes from the kidney to the bladder.
the urethra is the tube that carries urine, leading from the bladder to the outside of the body
organs of the excretory system inclue liver, skin, lungs, large intestine, urinary system; kidneys, ureters, urethra, bladder,
the excretory system’s function is to remove any dangerous, unnecessary excess material from metabolic reactions that occur in the body. mains homeostasis
the urethra is a tube leading from the bladder to the outside of the body. function is to remove urine (concentrated wastes) from the excretory system. expelled
the ureters are tubes that carry urine and transport it from the kidneys to bladder. 2 ureters, each connected to a kidney muscles in walls tighten and relax, forcing urine down.
the function of the excretory system is to remove unnecessary, harmful excess wastes from metabolic process that occur in the body. maintains homeostasis
homeostasis is a state of balance among the body, required for it to function correctly.
homeostasis is a state of balance among the body, required for proper functioning
the urethra is a tube carrying urine that leads from the bladder to outside the body. expels urine from the excretory system.
the ureters are tubes that lead from the kidneys to the bladder. carries urine, concentrate of wastes, to the bladder before it is expelled. muscular walls tighten to push urine downwards.
the skin’s function in the excretory system is the excrete sweat, which contains metabolic wastes such as urea, salts, water. additionally, the removal of sweat cools the body down.
the kidney’s function in the excretory system is to filter wastes from blood to form urine.
the function of the excretory system is to remove unnecessary, dangerous excess wastes from metabolic reactions that occur in the body. maintains homeostasis.
homeostasis is a state of balance among the body. it is required for th body to properly function.
the kidney’s function in the excretory system is to remove and filter wastes from the blood, such as urea, water, salts, hormones, drugs
the organs of the excretory system include the skin, liver, lungs, large intestine, urinal system organs; kidneys, bladder, ureters, urethra.
the liver’s function is to detoxify and break down any toxins and harmful chemicals that enter our body via the bloodstream
the function of the liver is to detoxify and break down any toxins and harmful chemicals that enter the body’s via the bloodstream
the kidneys filter wastes such as urea, water, salts, hormones, and drugs
the function of the excretory system is the remove dangerous, unnecessary excess wastes from metabolic processes/reactions in the body. maintains homeostasis, the state of balance among the body that ensures it functions properly
the ureters are tubes connected to either kidney. carries urine from the kidneys to the bladder for storage. 2. muscular walls contract and expand to push the urine down to the bladder.
the skin’s function in the excretory system is the secrete sweat which contains metabolic
metals:
lithium, berylllium, sodium, magnesium, aluminium, potassium, calcium, tin, gold, silver, lead, zinc, mercury
Li Be Na Mg Al K Ca Sn Au Ag Pb Zn Hg
a precipitate is the insoluble solid that settles to the bottom of a solution
a precipitation reaction is when two solutions with soluble compounds combine to form an insoluble precipitate that falls out of the solution
mass number = protons + neutrons = top left of element symbol
atomic number = protons = bottom left of element symbol
nucleon = P+n
signs of a chemical reaction include:
permanent change in temperature
permanent change in colour
fizzing/effervescence (gas given off)
energy given off (light, heat etc)
disappearance of an original substance (not always
appearance of a new substance
photosynthesis is a process that occurs in all plants in the presence of sunlight and chlorophyll where carbon dioxide and water react to produce glucose and oxygen. takes place in the chloroplast
cellular respiration is a process that occurs in all living things where glucose reacts with oxygen to produce carbon dioxide and water and energy in the form of ATP. takes place in the mitochondria.
an alloy is a mixture of two or more metallic elements, resulting in different physical properties
petroleum is a liquid mixture of hydrocarbons that can be extracted from rock strata and refined to produce fuels such as paraffin, diesel, and petrol.
an acid has a pH lower than 7 and reacts with metals to produce hydrogen. neutralises bases.
isobars are atoms of an element family where the amount of protons and neutrons are the same
isotopes are atoms of an element family where the amount of protons and neutrons are different
compound examples: H2O, C6H12O6, CO2,
element examples: O, Au, Na
a diatomic molecule has two atoms chemically bonded
carbon dioxide extinguishes a flame
an alkali is a soluble base
oxygen promotes burning so it will relight a glowing splint
the proton and neutron are each approximately 1840 times heavier than the electron
Copper, Iron, Gold, Lead, Silver, Zinc, Mercury, Iodine, Bromine, Tin
Cu Fe Au Pb Ag Zn Hg I Br Sn
Hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium magnesium aluminium silicon phosphorus sulfur chlorine argon potassium calcium
excretion is the removal of metabolic wastes from chemical reactions that occur in the body’s cells, such as salts, water, urea, and hormones. parts of the body that perform elimination include the skin, lungs, kidney.
elimination is the removal of wastes from the body’s digestive tract. these have not been metabolised, such as faeces, and are removed through the anus and rectum.
combustion is a type of chemical reaction where a fuel such as a hydrocarbon reacts with oxygen to produce carbon dioxide, water, and lets off a useful energy such as heat or light
neutralisation is a type of chemical reaction in which an acid reacts with an alkali/soluble base to produce a neutral solution consisting of a salt and water
hydrogen will make a popping sound when it comes into contact with a flame
the stomach is a bag shaped organ with an opening on either end. it is connected to the small intestine and esophagus. it has muscular walls and stomach acids such as hydrochloric. it churns and breaks down food chemically and physically. acts as a storage space for up to three hours before it sends the food to the small intestine. part of the gastrointestinal tract.
excretion is the removal of metabolic wastes from processes that occur in the body’s cells.
elimination is the removal of wastes from the digestive tract. these wastes have not been metabolised.
villi are small, finger like projections that line the small intestine. they increase the surface area of the small intestine for maximum absorption of nutrients, that are then diffused into the surrounding network of capillaries.
digestion is the breaking down of large insoluble food particles into simple, soluble molecules.
rectum serves as a storage space for waste before it heads to the anus to be eliminated part of the large intestine
all glands are organs, but not all organs are glands. a gland is just an organ that secretes products. there are two types, endocrine and exocrine.
a bunch of cells make tissue, a bunch of tissues make up organs, a bunch of organs make up an organ system, a bunch of organ systems make up an organism
teeth are hard, enamel covered projections embedded into the jaw. mechanically break down food by crushing, grinding, chewing etc
lumen refers to the hollow space inside a tubular structure
systemic and pulmonary circulation are the two types of circulation. systemic involves the blood going from the heart to the rest of the body, then back onces it is finished. it is controlled by the left side of the heart. pulmonary involves the blood being pumped from the heart to the lungs then back to the lungs once it has picked up oxygen. it is controlled by the right side of the heart.
arteries carry oxygenated blood with the exception of the pulmonary artery, which carries deoxygenated blood.
veins carry deoxygenated blood with the exception of the pulmonary vein which carries oxygenated blood.
the right side of the heart is thinner than the left side because it only needs to pump blood to the nearby lungs, which does not require too much pressure. the left is thicker because it needs to pump blood all around the body, exerting more pressure.
elimination is the removal of waste material from the digestive system. the waste material has not been involved in chemical reactions in the cells.
excretion is the removal of waste products from the body’s cells after being metabolised involved in chemical reactions.