4.4.1 Respiration

Question 1

outline why plants, animals and microorganisms need to respire, with reference to active transport and metabolic reactions;

Question 2

describe, with the aid of diagrams, the structure of ATP

Question 3

state that ATP provides the immediate source of energy for biological processes

Question 4

explain the importance of coenzymes in respiration, with reference to NAD and coenzyme A;

Question 5

state that glycolysis takes place in the cytoplasm

Question 6

outline the process of glycolysis beginning with the phosphorylation of glucose to hexose bisphosphate, splitting of hexose bisphosphate into two triose phosphate molecules and further oxidation to pyruvate, producing a small yield of ATP and reduced NAD;

Question 7

state that, during aerobic respiration in animals, pyruvate is actively transported into mitochondria;

Question 8

explain, with the aid of diagrams and electron micrographs, how the structure of mitochondria enables them to carry out their functions

Question 9

state that the link reaction takes place in the mitochondrial matrix

Question 10

outline the link reaction, with reference to decarboxylation of pyruvate to acetate and the reduction of NAD;

Question 11

explain that acetate is combined with coenzyme A to be carried to the next stage

Question 12

state that the Krebs cycle takes place in the mitochondrial matrix

Question 13

outline the Krebs cycle, with reference to the formation of citrate from acetate and oxaloacetate and the reconversion of citrate to oxaloacetate (names of intermediate compounds are not required)

Question 14

explain that during the Krebs cycle, decarboxylation and dehydrogenation occur, NAD and FAD are reduced and substrate level phosphorylation occurs;

Question 15

outline the process of oxidative phosphorylation, with reference to the roles of electron carriers, oxygen and the mitochondrial cristae

Question 16

outline the process of chemiosmosis, with reference to the electron transport chain, proton gradients and ATPsynthase (HSW7a);

Question 17

state that oxygen is the final electron acceptor in aerobic respiration

Question 18

evaluate the experimental evidence for the theory of chemiosmosis (HSW1);

Question 19

explain why the theoretical maximum yield of ATP per molecule of glucose is rarely, if ever, achieved in aerobic respiration

Question 20

explain why anaerobic respiration produces a much lower yield of ATP than aerobic respiration;

Question 21

compare and contrast anaerobic respiration in mammals and in yeast

Question 22

define the term respiratory substrate

Question 23

explain the difference in relative energy values of carbohydrate, lipid and protein respiratory substrates