Biology Past Paper Questions PDF

Toggle Masks Toggle Masks ventricles have more muscle than the atria and so the amplitude of...

Toggle Masks Toggle Masks ventricles have more muscle than the atria and so the amplitude of the QRS complex is bigger than that of the P wave. explain the shape of the graph. refer to enzymes. (7) when the enzyme and substrate are first mixed together, there are many substrate molecules. both enzyme and substrate molecules are in constant motion and collide. the higher the blood pressure, No cloze 2 found on card. Please substrate molecules bind to the the faster the blood flows. either add a cloze deletion, or use active site of the enzyme pressure and speed fall as the the Empty Cards tool. molecules. in a successful distance from the heart increases. More information collision, substrate is broken down and products are released. more active sites become filled with substrate molecules. the rate of the reaction depends on the number of free active sites, if all other condiitons are optimal and there's excess substrate. the enzyme concentration is the limiting factor because it controls the rate of the reaction. as the reaction proceeds, there's less substrate and more product. the enzyme concentration is constant. the substrate concentration is the limiting factor because it controls the rate of the reaction. eventually all of the substrate has been used and no more product can be formed so the line plateaus. where is DNA in eukaryotes and prokaryotes? eukaryotes - enclosed in the 1 mm to μm 1 μm to nm nucleus. 1000 μm 1000 nm prokaryotes - loose in the cytoplasm. 10 features of protoctista 10 features of plantae eukaryotic. eukaryotic. single-celled or multicellular. 2 advantages of eukaryotic cells multicellular. have nucleus. have nucleus. have mitochondria. harmful chemicals (like have mitochondria. some have chloroplasts. enzymes) are isolated. have chloroplasts. 80S ribosomes. substances with particular 80S ribosomes. have ER. functions (like chlorophyll) have ER. some have vacuoles. can be concentrated in one large permanent vacuole. some have cellulose cell area. cellulose cell wall. walls. autotrophic nutrition. autotrophic or heterotrophic nutrition. 2 anaerobic pathways to remove 2 anaerobic pathways to remove the hydrogen from NADred: the hydrogen from NADred: in animals, muscle cells may in animals, muscle cells may not get sufficient oxygen not get sufficient oxygen during vigorous exercise. during vigorous exercise. when deprived of oxygen, when deprived of oxygen, pyruvate is the hydrogen pyruvate is the hydrogen acceptor and is converted to acceptor and is converted to lactate, regenerating NAD. if lactate, regenerating NAD. if oxygen subsequently oxygen subsequently becomes available, the becomes available, the lactate can be respired to lactate can be respired to carbon dioxide and water, carbon dioxide and water, releasing the energy it releasing the energy it contains. contains. in various micro-organisms in various micro-organisms and in plant cells under and in plant cells under certain conditions, pyruvate certain conditions, pyruvate is converted to carbon is converted to carbon dioxide and to ethanal, a dioxide and to ethanal, a hydrogen acceptor, by hydrogen acceptor, by decarboxylase. ethanal is decarboxylase. ethanal is 2 components of chromosomes reduced to ethanol and NAD reduced to ethanol and NAD is regenerated, in alcoholic is regenerated, in alcoholic DNA. fermentation. this pathway is fermentation. this pathway is protein called histone. not reversible, so even if not reversible, so even if oxygen becomes available oxygen becomes available again, ethanol is not broken again, ethanol is not broken down. it accumulates in the down. it accumulates in the cells and can rise to toxic cells and can rise to toxic concentrations. concentrations.  2 examples of anatomical traits 2 differences between meiosis II and mitosis sharks, dolphins and 2 different polymers of alpha- penguins have streamlined in meiosis II: glucose molecules that constitute bodies - increase efficiency starch of catching food or escaping in metaphase, there's no predators. pairing of homologous some plants have flowers chromosomes. amylose. with nectar guides - indicate in anaphase, the chromatids amylopectin. the centre of the flower, the separate, instead of the source of nectar and pollen homologous chromosomes. for insects. this increases the amount of pollinators. 2 examples of intracellular 2 examples of behavioural enzymes that act in solution adapations enzymes that catalyse 2 examples of intracellular many plants flower in spring glucose breakdown in enzymes that're membrane-bound when pollinating insects glycolysis (a stage of have emerged, so that they respiration in solution in the on the cristae of can be pollinated. cytoplasm). mitochondria. mating rituals in animals enzymes in solution in the the grana of chloroplasts. increase an animal's chance stroma of the chloroplasts of reproducing. catalyse the synthesis of glucose. 2 examples of physiological adaptations 2 features of bile mammals and birds are 2 forces that draw water upwards contains bile salts which are in the transpiration stream endotherms - must avoid amphipathic (have wasting energy and must hydrophilic and hydrophobic maintain a stable internal the cohesive forces between parts) - emulsify lipids in temperature. water molecules. food. leaves fall of some plants the adhesive forces between alkaline - neutralises the acid when temperature and light the water molecules and the in food coming from the intensity decrease in autumn hydrophilic lining of the stomach. provides a suitable - so they don't lose water by xylem vessels. pH for the enzymes in the transpiration and risk small intestine. dehydration in winter when water may be frozen. 2 functions of ileum in the 2 functions of mouth in the 2 functions of the plasmodesmata digestive system digestive system allow cell-to-cell transport. digestion of carbohydrates, ingestion. allow cell-to-cell fats and proteins. digestion of starch. communication. absorption of digested food.  2 isomers of glucose alpha-glucose. beta-glucose. 2 hosts of the pork tapeworm 2 functions of xylem primary host - humans. transport of water and secondary host - pigs. dissolved minerals. provides mechanical strength and support. the tapeworm's life cycle requires it to alternate between the pig and the human. 2 parts of the double circulatory system and what they serve the pulmonary circulation - serves the lungs. the right side of the heart pumps deoxygenated blood to the lungs. oxygenated blood 2 main components of cell returns from the lungs to the 2 main cell types in xylem membranes left side of the heart. the systemic circulation - vessels. proteins serves the body tissues. the tracheids. phospholipids left side of the heart pumps the oxygenated blood to the tissues. deoxygenated blood from the body returns to the right side of the heart. in each circuit the blood passes through the heart twice, once through the right side and once through the left side. 2 parts of the endosymbiotic 2 places that have phospholipids theory 2 parts of the small intestine in biological membranes. the division of chloroplasts in the myelin sheath that closely resembles that of duodenum. surrounds the axons of nerve free-living cyanobacteria. ileum. cells, for electrical mitochondria were once insulation. independent bacteria. 2 purine bases adenine. guanine. 2 places where goblet cells are in trachea, bronchi, 2 problems the faulty functioning bronchioles - trap bacteria of the valves lead to and dust. in stomach - secreted at varicose veins. gastric pit. mucus forms a heart failure. lining which protects the stomach wall from the  enzymes. lubricates the food. 2 reasons why meiosis is 2 reasons why food must be important digested it keeps the chromosome because the molecules are: 2 reasons why humans have an number constant from one insoluble and too big to cross internal gas exchange surface generation to the next. membranes and be absorbed it creates genetic variation in into the blood. the gametes, and therefore reduces water loss. the zygotes that they polymers, and must be reduces heat loss. converted to their monomers produce. this is by crossing so they can be rebuilt into over during prophase I, and molecules needed by body independent assortment at cells. metaphase I and metaphase II. 2 roles of DNA replication - DNA consists of 2 complementary strands, 2 reasons why mitochondria the base sequence of one 2 reasons why red blood cells are strand determining the base being cylindrical is better than biconcave discs sequence of the other. if 2 being spherical strands of a double helix are the surface area is larger separated, 2 identical double gives them a larger surface than a plane disc, so more helixes can be formed, as area to volume ratio. oxygen diffuses across the each parent strand acts as a reduces the diffusion membrane. template for the synthesis of distance between the edge the thin centre reduces the a new complementary and the centre, making diffusion distance, making strand. aerobic respiration more gas exchange faster. protein synthesis - the efficient. sequence of bases represents the information carried in DNA and determines the sequence of amino acids in proteins. 2 significant types of reaction in the Krebs cycle (4) there are 2 significant types of reaction: decarboxylation - occurs twice. decarboxylases remove carbon dioxide from the -COOH groups of Krebs cycle intermediates. 6C acid -> 5C acid -> 4C acid. dehydrogenation - occurs 4 times. dehydrogenases remove pairs of hydrogen atoms from Krebs cycle  intermediates. they're collected by hydrogen carriers giving 3 molecules of NADred and one molecule of FADred. the acetate group from the 2 stages of atrial systole original glucose molecule is entirely broken down to carbon 1. the atrium walls contract, 2 stages of negative pressure dioxide and water. the energy in increasing the blood breathing the bonds of the glucose molecule pressure in the atria. is carried by electrons in the 2. this pushes the blood hydrogen atoms in the through the tricuspid and inspiration. NADred and FADred. bicuspid valves down into expiration. the ventricles, which are each turn of the Krebs cycle relaxed. produces: one ATP produced by substrate-level phosphorylation. 3 molecules of NADred. one molecule of FADred. 2 molecules of carbon dioxide. 2 steps of DNA hybridisation 2 things potometer can measure 2 things pyruvate is converted to 1. DNA from both species is in anaerobic respiration extracted, separated and cut water uptake by the same pyruvate is not transferred to the into fragments. shoot under different mitochondria but is converted (in 2. the fragments from the 2 conditions. cytoplasm) to: species are mixed and, compare the uptake by leafy where they have shoots of different species ethanol in plants. complementary base under the same conditions. lactate in mammals. sequences, they hybridise together. 2 things that make the cell wall have high mechanical strength 2 things that maintain the diffusion gradients of oxygen and the structure of cellulose carbon dioxide between the inside microfibrils and their 2 things that chitin is found in laminated arrangement and outside of a leaf make the cell wall very exoskeleton of insects. strong. the mitochondria carrying fungal cell walls. when the vacuole is full of out respiration. solution, cell contents push the chloroplasts carrying out against the cell wall which photosynthesis. resists expansion, and so the cell becomes turgid,  supporting the plant. 2 things that modify the heart 2 things that organisms store 2 things that're found from an rate chemical energy in ECG analysis nervous stimulation. lipids. heart rate. hormonal stimulation. carbohydrates. heart rhythm. 2 things this graph shows 2 types of closed circulatory 2 types of autotrophic organisms systems photoautotrophic. single circulation. chemoautotrophic. at higher concentration double circulation. differences across a membrane, the rate of uptake increases and reaches a plateau, where the carrier proteins are saturated. the rate of uptake is reduced with the addition of a respiratory inhibitor, meaning the process requires ATP, meaning active transport must be taking place. 2 types of intrinsic proteins 2 types of endocytosis carrier proteins - transport 2 types of lipids water-soluble substances phagocytosis. across. triglycerides. pinocytosis. channel proteins - allow phospholipids. active transport of ions across. 2 types of organic bases pyrimidine - thymine, cytosine, uracil. purine - adenine, guaninine. 2 types of metabolic pathways 2 types of parasites anabolic reactions - building endoparasites - live in body up molecules. of host. catabolic reactions - ectoparasites - live on breaking molecules down. surface of body of host.  2 uses of calcium ions (Ca2+) 2 types of transport proteins 2 uses of immobilised enzymes important structural channel proteins. components of bones and lactose-free milk. carrier proteins. teeth in mammals. biosensors. components of plant cell walls, providing strength. 2 ways meiosis create genetic variation in the gametes, and therefore the zygotes that they produce. 2 uses of magnesium 2 uses of phosphate ions (PO43-) crossing over during prophase I. plants need it to make independent assortment at: chlorophyll, so it's essential constituents of nucleotides. metaphase I - so that the for photosynthesis. constituents of daughter cells contain mammals need magnesium phospholipids. different combinations of for their bones. maternal and paternal chromosomes. metaphase II - so daughter cells have different combinations of chromatids. 2 ways the water potential of the xylem is made more negative than the water potential of the 2 ways to follow the progression endodermal cells of an enzyme-catalysed reaction 2 ways proto-oncogenes can for a given concentration of become oncogenes the water potential of the substrate endodermis cells is raised by if they become mutated. water being driven in by the measuring the formation of if the cell is infected with a Casparian strip. product. virus. the water potential of the measuring the xylem is decreased by active disappearance of substrate. transport of mineral salts from the endodermis and pericycle into the xylem. 3 adaptations of mesophytes shed their leaves before winter so that they don't lose 3 adaptations of capillaries water by transpiration, when 3 advantages of the binomial water may be scarce. system have thin, permeable walls. the aerial parts of many non- have large surface area for woody plants die off in unambiguous naming. exchange of materials. winter so they aren't based on Latin, so can be  blood flows very slowly exposed to frost or cold used all over the world. through capillaries, allowing winds, but their implies that 2 species time for exchange of underground organs survive. sharing part of their name materials. most annual mesophytes live are closely related. through the winter as dormant seeds, with such a low metabolic rate that almost no water is required. 3 cellular processes that inorganic ions are used for 3 components of the nucleus 3 domains muscle contraction. nuclear envelope. bacteria. nervous coordination. nucleoplasm. archaea. maintaining water potential nucleolus. eukaryota. in cells and blood. 3 elements in carbohydrates 3 elements in lipids 3 features of chitin carbon. carbon. strong. hydrogen. hydrogen. waterproof. oxygen. oxygen. lightweight. 3 features of red blood cells 3 functions of extrinsic proteins 3 functions of glycoproteins (erythrocytes) provide structural support. involved in: contain the pigment form recognition sites, by haemoglobin. identifying cells. cell-to-cell recognition. are biconcave discs. form receptor sites for signalling. have no nucleus. hormone attachment. hormone reception. 3 functions of the cell wall 3 groups of organisms that're transport - gaps between recognised depending on their cellulose fibres make the cell respiration wall fully permeable to water and dissolved minerals and obligate aerobes - living ions. organisms that use aerobic mechanical strength - the respiration, and break down structure of cellulose 3 globular proteins substrates using oxygen. microfibrils and their releases a large amount of laminated arrangement energy. globin. make cell wall very strong. facultative anaerobes - carbohydrase. when vacuole is full of micro-organisms that respire immunoglobulin. solution, cell contents push aerobically, but can also against cell wall which respire without oxygen. resists expansion and cell obligate anaerobes - species becomes turgid, supporting of bacteria and Archaea that the plant. use anaerobic respiration. communication between they respire without oxygen cells - cell walls have pores and can't grow in its where plasmodesmata pass presence. through. 3 non-proteins that are combined with polypeptides to chemically 3 main mechanisms for movement 3 measures that reduce tapeworm modify them of water in plants infection carbohydrates - making cohesion-tension. education about the cause. glycoproteins. capillarity. improved sanitation. lipids - making lipoproteins. root pressure. frequent inspection of meat. phosphates - making  phospho-proteins. 3 possibilities for the mechanism of DNA replication conservative replication - where the parental double helix remains intact, and is conserved. a whole new double helix is made. 3 parts of saliva semi-conservative replication - where the parental double 3 places where smooth muscle is helix separates into 2 amylase - digests starch into located strands, each of which acts maltose. as a template for the HCO3- and CO32- ions - make synthesis of a new strand. the pH in the mouth slightly skin. alkaline which is optimum blood vessel walls. pH for amylase. digestive and respiratory mucus - lubricates the food's tracts. passage down the esophagus. dispersive replication - where the 2 new double helixes contain fragments from both strands of the parental double helix. 3 pyrimidine bases thymine. cytosine. uracil. 3 reasons why a classification 3 principles of cell theory system is needed all living organisms are allows us to see evolutionary made of one or more cells. relationships. the cell is the basic unit of if a new animal is life. discovered, some of its cells can only be made from characteristics can be pre-existing cells. predicted. easier to communicate.  3 stages in the louse life cycle 3 reasons why turgor is important 3 sites where enzymes act to plants 1. the nits are empty eggs. extracellular. 2. after about a week an egg provides support. intracellular, in solution. hatches into a nymph. maintains their shape. intracellular, membrane- 3. nymphs become adult after holds them upright. bound. about a week and like the adult, they feed on blood. 3 stages of the cell cycle 1. interphase - synthesis and 3 things longer fatty acid chains growth. have more of (6) 3 stages of the cardiac cycle 2. mitosis - formation of 2 genetically identical more carbon atoms - more daughter nuclei. has 4 carbon dioxide is produced. 1. atrial systole. stages: prophase, muscles have a limited blood 2. ventricular systole. metaphase, anaphase, supply and if they respired 3. diastole. telophase. fat, instead of glucose, they 3. cytokinesis - the division of would produce more carbon the cytoplasm to form 2 dioxide than could be daughter cells. removed quickly enough. more hydrogen atoms - more NAD is reduced, so more ATP is produced. this is why tissues with a rich blood supply respire fat as the large amount of ATP they produce is readily transported around the body. more hydrogen atoms - more water is produced. this metabolic water is very important for desert animals and explains why they respire fat. 3 things that can happen if the genes that control the cell cycle 3 things that can denature are damaged 3 things that can mutate DNA enzymes cells may fail to divide. radiation. high temperatures. cells may divide too some chemicals. extremes of pH. frequently. some viruses. organic solvents. cells may divide at the wrong time. 3 things that gastric juice contains peptidases - secreted by chief cells. pepsinogen (inactive enzyme) is secreted 3 things that make up a and activated by H+ ions to nucleotide pepsin (an endopeptidase) which hydrolyses protein to pentose sugar - ribose in polypeptides. RNA and deoxyribose in hydrochloric acid - secreted DNA. by oxyntic cells. lowers the organic base. 3 things that taxonomy allows us pH of the stomach contents phosphate group - has the to do to the optimum pH for the same structure in all enzymes. kills bacteria. nucleotides. discover and describe mucus - secreted by goblet biological diversity.  cells. mucus forms a lining investigate evolutionary which protects the stomach relationships between wall from the enzymes. organisms. lubricates the food. classify organisms to reflect their evolutionary relationships. 3 things that this graph of oxygen dissociation curve for adult human haemoglobin shows. 3 types of RNA messenger RNA (mRNA) - long, single stranded molecule. synthesised in the 3 things that're lost if biodiversity nucleus and carries the decreases genetic code from the DNA to the ribosomes in the cytoplasm. potential new foods are lost. ribosomal RNA (rRNA) - sources of new, useful found in the cytoplasm. characteristics to breed into consists of large, complex it's an oxygen dissociation crops (like disease molecules. constituent of curve. resistance) are lost. ribosomes. the oxygen affinity of potential new medicinal transfer RNA (tRNA) - small haemoglobin is high at a drugs and new raw materials single-stranded molecule, high partial pressure of are lost. which folds so that in places, oxygen and oxyhaemoglobin there're base sequences doesn't release its oxygen. forming complementary oxygen affinity reduces as pairs. transport specific the partial pressure of amino acids to the ribosomes oxygen decreases, and in protein synthesis. oxygen is readily released, meeting respiratory demands. the graph shows that a very small decrease in the oxygen partial pressure leads to a lot of oxygen dissociating from haemoglobin. 3 types of blood vessels 3 types of heterotrophic nutrition 3 types of muscle arteries. saprotrophic nutrition. cardiac muscle. veins. parasitic nutrition. skeletal muscle. capillaries. holozoic nutrition. smooth muscle. 3 ways how biodiversity can 3 types of phosphorylation increase or decrease  oxidative phosphorylation - succession - over time, a the energy for making the community of organisms ATP comes from oxidation- 3 ways carbon dioxide is changes its habitat, making reduction reactions. transported it more suitable for other photophosphorylation - the species. energy for making the ATP in solution in the plasma. natural selection - can comes from light. as the hydrogen carbonate generate and change substrate-level biodiversity. ion, HCO3-. phosphorylation - occurs human influence - human when phosphate groups are bound to haemoglobin as activity has made the transferred from donor carbamino-haemoglobin. environment less hospitable molecules, or when enough to living organisms, energy is released for a decreasing their biodiversity, reaction to bind ADP to and in some cases led to inorganic phosphate. extinction. 4 advantages of using ATP as an intermediate in providing energy, instead of glucose directly. 3 ways water is transported around the plant the hydrolysis of ATP to ADP involves a single reaction apoplast pathway. that releases energy 3 ways plants and animals are symplast pathway. immediately. the breakdown used to support human vacuolar pathway. of glucose involves many civilisation intermediates and it takes longer for energy to be plant species provide the released. staple foods (like wheat, only one enzyme is needed to rice). release energy from ATP, but medicinal drugs are derived many are needed to release from plants and fungi (like energy from glucose. antibiotics) ATP releases energy in small living organisms provide amounts, when and where important raw materials (like it's needed. glucose contains rubber, cotton). large amounts of energy which would be released all at once. ATP provides a common source of energy for many different chemical reactions, increasing efficiency and control by the cell. 4 changes in prophase 1. the chromosomes condense. 2. the centriole pairs separate and move to the opposite ends of the cell. 3. protein microtubules form, radiating from each centriole, making the 4 features of carnivorous mammal spindle. spindle fibres extend teeth 4 features that specialised from pole to pole and from respiratory surfaces need for gas pole to the centromere of the sharp incisors - grip and exchange each chromosome. 4. at the end of prophase, the tear muscle from bone. nuclear envelope the canine teeth - large, a large SA - maximises the disintegrates and the curved and pointed for absorption of gases. nucleolus disappears. piercing and seizing prey, for moist - ensures the efficient tearing muscle and killing. diffusion of gases. the premolars and molars thin - short diffusion pathway the longest stage of mitosis. have cusps - sharp points for gases. that cut and crush. good blood supply - to carnassials (a pair of transport gases to and from specialised cheek teeth) - the gas exchange surface slide past each other, and maintain the shearing muscle off the concentration.  bone. 4 functions of monosaccharides 4 fibrous proteins source of energy in 4 functions of the human gut respiration - C-H and C-C bonds are broken to release collagen. ingestion. energy, which is transferred keratin. digestion. to make ATP. actin. absorption. building blocks for larger myosin. egestion. molecules. intermediates in reactions. constituents of nucleotides. 4 kingdoms of eukaryota plantae. animalia. fungi. protoctista. 4 organic bases in RNA purine bases: 4 parts of the large intestine adenine. caecum. guanine. appendix. colon. pyrimidine bases: rectum. cytosine. uracil. 4 products of each turn of the 4 properties that enzymes and 4 processes that involve active Krebs cycle chemical catalysts share in the transport reactions they catalyse one ATP produced by muscle contraction. substrate-level they speed up reactions. nerve impulse transmission. phosphorylation. they aren't used up. absorption of glucose in the 3 molecules of NADred. they aren't changed. kidney. one molecule of FADred. they have a high turn-over mineral uptake into plant 2 molecules of carbon number - they catalyse many root hairs. dioxide. reactions per second. 4 stages of aerobic respiration  glycolysis - generates pyruvate, ATP, NADred. 4 roles of triglycerides the link reaction - pyruvate is converted into acetyl energy reserves in both coenzyme A. plants and animals - lipids the Krebs cycle - generates 4 reasons why the contain more carbon- polysaccharides starch and carbon dioxide, NADred, hydrogen bonds than glycogen are more suitable than FADred. carbohydrates. glucose for storage thermal insulation - when the electron transport chain - stored under the skin, lipids generates ATP from ADP and they are insoluble so have no insulate against heat loss in inorganic phosphate. osmotic effect. the cold or heat gain when they can't diffuse out of the it's hot. cell. protection - fat is stored they are compact molecules around internal organs, and can be stored in a small protecting against physical space. damage. they carry a lot of energy in metabolic water - water their C-H and C-C bonds. released during chemical reactions in the body. triglycerides produce a lot of metabolic water when oxidised. 4 steps of fat becoming a respiratory substrate 1. fat is hydrolysed into its constituent molecules - glycerol and fatty acids. 2. the glycerol is phosphorylated with ATP, dehydrogenated with NAD and converted into triose phosphate, which enters the glycolysis pathway. 4 stages of diastole 4 stages of ventricular systole 1. the ventricles relax. 1. the ventricle walls contract, 3. the long chain fatty acid 2. the volume of the ventricles increasing the blood molecules are split into 2- increases and so the pressure in the ventricles. carbon fragments that enter pressure in the ventricles 2. the blood cannot flow back the Krebs cycle as acetyl decreases, risking the blood from the ventricles into the CoA. in the pulmonary artery and atria because the atrio- 4. hydrogen is released, picked aorta flowing backwards into ventricular valves are closed up by NAD and fed into the the ventricles. by the rise in ventricular electron transport chain. this 3. that tendency to flow pressure. produces very large numbers backwards causes the semi- 3. this forces blood up through of ATP molecules (the actual lunar valves at their bases to the semi-lunar valves, out of number depends on the shut, preventing blood re- the heart, into the pulmonary length of the hydrocarbon entering the ventricles. artery and the aorta. chain of the fatty acid). 4. the atria also relax so blood 4. the pulmonary artery carries from the vena cavae and deoxygenated blood to the pulmonary veins enters the lungs, and the aorta carries atria and the cardiac cycle oxygenated blood to the rest longer fatty acid chains have: starts again. of the body. more carbon atoms, so more  carbon dioxide is produced. muscles have a limited blood supply and if they respired fat, rather than glucose, they would produce more carbon dioxide than could be removed quickly enough. more hydrogen atoms, so more NAD is reduced, so more ATP is produced. this is why tissues with a rich blood supply, such as the liver, respire fat: the large amount of ATP they produce is readily transported around the body. more hydrogen atoms, so more water is produced. this metabolic water is very important for desert animals and explains why they respire fat. 4 steps of protein becoming a respiratory substrate 1. tissue protein is mobilised to supply energy. 2. protein is hydrolysed into its constituent amino acids, which are deaminated in the 4 steps of granulocytes engulfing 4 steps of granulocytes engulfing liver. bacteria: bacteria: 3. the amino group is converted into urea and excreted. the granulocytes engulf the the granulocytes engulf the 4. the residue is converted to bacteria. bacteria. acetyl CoA, pyruvate or a lysosome fuses with the a lysosome fuses with the another Krebs cycle vesicle formed. vesicle formed. intermediate, and oxidised: the enzymes digest the cells. the enzymes digest the cells. the products are absorbed the products are absorbed into the cytoplasm. into the cytoplasm. 4 steps of ventilation in fish 1. the fish's mouth opens and the buccal cavity floor lowers. the operculum is 4 tissue layers of the gut closed. 4 types of human teeth 2. this lowers the pressure in mucosa - the innermost the buccal cavity, and water layer. incisors. is drawn in. submucosa. canines. 3. the mouth closes and the inner circular muscles and premolars. floor of the buccal cavity outer longitudinal muscles. molars. raises. serosa - the outermost layer. 4. the operculum opens, increasing the pressure in the buccal cavity, forcing water over the gills and out of the operculum. 4 ways how DNA is suited to its 4 ways humans have affected functions biodiversity it's a very stable molecule farming, roads and industry - and its information content destroyed habitats and passes unchanged from reduced the numbers of generation to generation. individuals and driven to 4 ways of assessing relatedness it's a very large molecule and extinction many species. with genetic evidence carries a large amount of over-fishing - reduced fish genetic information. stocks and has stressed DNA sequences. the 2 strands are able to productive, diverse areas in DNA hybridisation. separate, as they're held the ocean. trawlers disrupt amino acid sequences. together by hydrogen bonds. habitats, damaging immunology. as the base pairs are on the populations of the species inside of the double helix, living there. within the deoxyribose- misuse of land - increased phosphate backbones, the the area of deserts. genetic information is pollution of riverse by protected. industrial chemicals. 5 adaptations of hydrophytes 5 advantages of immobilised 5 adaptations of xerophytes enzymes water is a supportive medium so they have little rolled leaves - reduces leaf increased stability and support tissues. area exposed to air. function over a wider range surrounded by water so little sunken stomata - humid air of temperature and pH than need for transport tissue, so is trapped in the pits outside enzymes free in solution. xylem is poorly developed. the stomata, reducing the products are not leaves have little cuticle water potential gradient. contaminated with the because there's no need to hairs - stiff, interlocking enzyme. prevent water loss. hairs trap water vapour and enzymes are easily stomata on upper surface of reduce the water potential recovered for reuse. floating leaves because the gradient. a sequence of columns can lower surface is in the water. thick cuticle - wax is water be used so several enzymes stems and leaves have large proof, reducing water loss. with differing pH or optimum air spaces, continuous down fibres of sclerenchyma are temperatures can be used in to their roots, forming a stiff - the leaf shape is one process. reservoir of oxygen and maintained even when the enzymes can be easily added carbon dioxide, which create cells become flaccid. or removed, giving greater buoyancy. control over the reaction. 5 characteristics of genetic code the code is a triplet code - 3 bases code for each amino acid. 5 conditions of the gut that the the code is degenerate - there are 64 possible codes pork tapeworm needs to survive 5 factors affecting rate of but only 20 amino acids are transpiration found in proteins. it's surrounded by digestive the code is punctuated - juices and mucus. genetic factors - the number, there are 3 triplet codes that peristalsis produces constant distribution and size of the don't code for amino acids. motion. stomata. in mRNA, they're called stop it experiences pH changes in temperature. codons and mark the end of its passage to the duodenum. humidity. a portion to be translated. it's exposed to the host's air speed. the code is universal - in all immune system. light intensity. organisms known, the same if the host dies, so does the triplet codes for the same parasite. amino acid. the code is non-overlapping - each base occurs in only one triplet. 5 features of transport systems in animals a suitable medium in which to carry materials. a pump for moving the blood. 5 functions of the golgi body valves to maintain the flow in 5 functions of proteins one direction. modifies proteins and lipids. enzymes. produces glycoproteins. some systems also have: antibodies. transports lipids and hormones. digestive enzymes. a respiratory pigment which transport proteins. synthesises secretory increases the volume of forming structures. vesicles. oxygen that can be packages proteins. transported. a system of vessels with a branching network to distribute the transport medium to all parts of the body. 5 roles of ATP 5 things about translocation the 6 differences between mitosis in mass flow theory doesn't explain animal and plant cells metabolic processes - to build large, complex the rate of phloem transport in animal cells: molecules from smaller, is much faster than if the simpler molecules. substances were moving by cells become rounded before active transport - the change diffusion. mitosis. the shape of carrier proteins it doesn't take into account centrioles are present. in membranes and allow the sieve plates. cleavage furrow develops molecules/ions to be moved sucrose and amino acids from the outside in wards. against a concentration move at different rates and spindle degenerates at gradient. in different directions in the telophase. movement - for muscle same tissue. occurs in epithelia, bone contraction. phloem has a relatively high marrow, other sites. nerve transmission - sodium- oxygen consumption, and translocation is slowed or in plant cells: potassium pumps actively transport sodium and stopped at low temperatures or if respiratory poisons are no shape change. potassium ions across the applied. no centrioles. axon membrane. the companion cells are cell plate develops from the secretion - the packaging biochemically very active, centre outwards. and transport of secretory but the mass flow theory spindle remains throughout products into vesicles in doesn't suggest a role for new cell wall formation. cells. them. occurs in meristems. 6 stages of the flow of blood through the left side of the heart 1. the left atrium relaxes and receives oxygenated blood from the pulmonary vein. 2. when full, the pressure forces open the bicuspid valve between the atrium and ventricle. 3. relaxation of the left ventricle draws blood from the left atrium. 4. the left atrium contracts, pushing the remaining blood into the left ventricle, 6 factors of the rate of diffusion through the valve. 5. with the left atrium relaxed 6 elements in proteins the concentration gradient. and bicuspid valve closed, the diffusion distance. the left ventricle contracts. carbon. its strong muscular wall the surface area of the hydrogen. exerts high pressure. membrane. oxygen. 6. this pressure pushes blood the sizes of the diffusing  nitrogen. molecules. up through the semi-lunar sulfur. the nature of the diffusing valves into the aorta. the phosphorus. molecules. ventricular pressure closes temperature. the bicuspid valve, preventing backflow of blood into the left atrium. 6 steps of guard cells opening: 6 steps of guard cells opening: 1. the chloroplasts in the guard 1. the chloroplasts in the guard cells photosynthesise, cells photosynthesise, producing ATP. producing ATP. 2. this ATP provides energy for 2. this ATP provides energy for 6 steps of natural selection active transport of potassium active transport of potassium ions into the guard cells from ions into the guard cells from 1. mutation causes differences the surrounding epidermal the surrounding epidermal in DNA. cells. cells. 2. variation causes different 3. stored, insoluble starch is 3. stored, insoluble starch is physical appearance or converted into soluble converted into soluble behaviour. malate. malate. 3. competitive advantage - 4. the potassium ions and 4. the potassium ions and some are more suited to the malate ions lower the water malate ions lower the water environment than others and potential in the guard cells, potential in the guard cells, out-compete them for making it more negative. making it more negative. resources. 5. water enters the guard cells 5. water enters the guard cells 4. those more suited to the by osmosis. by osmosis. environment survive better. 6. the outer cell walls are 6. the outer cell walls are 5. reproduction - those more thinner than the inner cell thinner than the inner cell suited to the environment walls. the guard cells expand walls. the guard cells expand have more offspring. as they absorb water but less as they absorb water but less 6. offspring inherit the so in the areas where the cell so in the areas where the cell advantageous alleles, so wall is thick. turgor pushes wall is thick. turgor pushes they're also suited to the outer wall outwards to open outer wall outwards to open environment. stomata. stomata. at night, the reverse process at night, the reverse process occurs and the pore closes. occurs and the pore closes. 7 adaptations of the tapeworm suckers and hooks - attach it to the duodenum wall. thick body covering - protect 6 steps of using the binomial it from the host's immune system responses. the ability to make enzyme 1. each organism has 2 names, inhibitors - prevent the host's 7 features of prokaryota its genus and its species. enzymes digesting it. 2. the genus name is the first no digestive system, but a prokaryotic. word and has a capital letter. large surface area to volume single-celled. 3. the species name comes ratio - digested food is some have mesosomes. second and doesn't have a absorbed over its whole body some have photosynthetic capital letter. surface. lamellae. 4. the first time the scientific unnecessary organs have 70S ribosomes.  name is used in a text, it's degenerated - lives in a peptidoglycan cell wall. written in full. stable environment so don't saprotrophic, parasitic or 5. if used again, the genus need to move or sense autotrophic nutrition. name may be abbreviated. environment. most of the 6. both names are printed in body is adapted for italics, or underlined when reproduction. hand-written. hermaphrodite - each proglottid contains male and female reproductive organs. the eggs have resistant shells - survive until eaten by the secondary host. 7 things the tapeworm must do to survive the harsh environment of the gut 9 features of animalia 9 features of fungi penetrate the host. eukaryotic. eukaryotic. attach to the host. multicellular. single-celled. protect itself against the have nucleus. have nucleus. host's immune responses. have mitochondria. have mitochondria. only develop organs that're 80S ribosomes. 80S ribosomes. essential for survival. have ER. have ER. produce many eggs - gives small, scattered, temporary large permanent vacuole. high chance of transmission vacuole. chitin cell wall. to the secondary host. heterotrophic nutrition. saprotrophic or parasitic have an intermediate host. have nervous coordination. nutrition. have resistant stages while away from a host. ATP (2) the molecule that makes energy available when it's needed for biological processes. adenosine triphosphate. it's a nucleotide. ATP is synthesised when energy ATP is called the energy currency is made available (like of the cell because it's involved mitochondria), and it's broken when energy changes happen down when energy is needed (muscle contraction). Cellulose Digestion  Casparian strip the impermeable band of suberin in the cell walls of endodermal cells, blocking the movement of water in the apoplast, driving it into the cytoplasm. the grass is cut by the teeth and mixed with saliva to form cud, which is swallowed Brunner's glands down the oesophagus to the rumen. release alkaline secretion which the rumen (A) is the chamber increases pH of stomach contents in which the food mixes with microbes. they secrete cellulase which digest cellulose into glucose. this is fermented to organic acids that're absorbed into the blood, and are an energy source for the ruminant. the waste products, carbon dioxide and methane, are released. C6H12O6 -> 2CH3COOH + CO2 + CH4 the fermented grass passes to the reticulum (B) and is re-formed into cud. it's regurgitated into the mouth for further chewing. cud may be swallowed and regurgitated to the mouth several times. the cud passes next into the omasum (C) where water and organic acids made from fermented glucose are absorbed into the blood. the abomasum (D) is the stomach where protein is digested by pepsin. digested food passes to the small intestine, from where the products of digestion are absorbed into the blood. Cellulose Digestion Cellulose Digestion Cellulose Digestion  the grass is cut by the teeth the grass is cut by the teeth the grass is cut by the teeth and mixed with saliva to and mixed with saliva to and mixed with saliva to form cud, which is swallowed form cud, which is swallowed form cud, which is swallowed down the oesophagus to the down the oesophagus to the down the oesophagus to the rumen. rumen. rumen. the rumen (A) is the chamber the rumen (A) is the chamber the rumen (A) is the chamber in which the food mixes with in which the food mixes with in which the food mixes with microbes. they secrete microbes. they secrete microbes. they secrete cellulase which digest cellulase which digest cellulase which digest cellulose into glucose. this is cellulose into glucose. this is cellulose into glucose. this is fermented to organic acids fermented to organic acids fermented to organic acids that're absorbed into the that're absorbed into the that're absorbed into the blood, and are an energy blood, and are an energy blood, and are an energy source for the ruminant. source for the ruminant. source for the ruminant. the waste products, carbon the waste products, carbon the waste products, carbon dioxide and methane, are dioxide and methane, are dioxide and methane, are released. released. released. C6H12O6 -> 2CH3COOH + C6H12O6 -> 2CH3COOH + C6H12O6 -> 2CH3COOH + CO2 + CH4 CO2 + CH4 CO2 + CH4 the fermented grass passes the fermented grass passes the fermented grass passes to the reticulum (B) and is to the reticulum (B) and is to the reticulum (B) and is re-formed into cud. it's re-formed into cud. it's re-formed into cud. it's regurgitated into the mouth regurgitated into the mouth regurgitated into the mouth for further chewing. for further chewing. for further chewing. cud may be swallowed and cud may be swallowed and cud may be swallowed and regurgitated to the mouth regurgitated to the mouth regurgitated to the mouth several times. several times. several times. the cud passes next into the the cud passes next into the the cud passes next into the omasum (C) where water omasum (C) where water omasum (C) where water and organic acids made from and organic acids made from and organic acids made from fermented glucose are fermented glucose are fermented glucose are absorbed into the blood. absorbed into the blood. absorbed into the blood. the abomasum (D) is the the abomasum (D) is the the abomasum (D) is the stomach where protein is stomach where protein is stomach where protein is digested by pepsin. digested by pepsin. digested by pepsin. digested food passes to the digested food passes to the digested food passes to the small intestine, from where small intestine, from where small intestine, from where the products of digestion are the products of digestion are the products of digestion are absorbed into the blood. absorbed into the blood. absorbed into the blood. Cohesion-tension Cohesion-tension Cohesion-tension water vapour evaporates from water vapour evaporates from water vapour evaporates from leaf cells into the air spaces and leaf cells into the air spaces and leaf cells into the air spaces and diffuses out through the stomata diffuses out through the stomata diffuses out through the stomata into the atmosphere. into the atmosphere. into the atmosphere. this draws water across the cells this draws water across the cells this draws water across the cells of the leaf in the apoplast, of the leaf in the apoplast, of the leaf in the apoplast, symplast and vacuolar pathways, symplast and vacuolar pathways, symplast and vacuolar pathways, from the xylem. from the xylem. from the xylem. as water molecules leave xylem as water molecules leave xylem as water molecules leave xylem cells in the leaf, they pull up other cells in the leaf, they pull up other cells in the leaf, they pull up other water molecules behind them in water molecules behind them in water molecules behind them in  the xylem. the xylem. the xylem. the water molecules all move the water molecules all move the water molecules all move because they have cohesion. this because they have cohesion. this because they have cohesion. this continuous pull produces tension continuous pull produces tension continuous pull produces tension in the water column. in the water column. in the water column. the charges on the water the charges on the water the charges on the water molecules also cause attraction to molecules also cause attraction to molecules also cause attraction to the hydrophilic lining of the the hydrophilic lining of the the hydrophilic lining of the vessels. this is adhesion, and vessels. this is adhesion, and vessels. this