IB Biology HL C1.2 Cell respiration Questions

a. used as a source/(temporary) store of energy / is the energy currency of the cell;

b. releases energy when converted to ADP/when a phosphate is removed;

c. amount of energy released can be used/sufficient for (many metabolic) tasks;

d. active transport/another valid example;

e. ATP to ADP conversion is reversible / ATP can be regenerated from ADP;

f. can be produced in different ways/using energy from different sources/by aerobic or anaerobic respiration;

g. stable within cell so does not release energy prematurely/before needed;

h. small molecule/soluble so can move easily/quickly (through the cell);

i. cannot diffuse through membranes so is not lost from cell/to the environment;

h. The idea of ATP being small/soluble must be there along with its moveability.

a. movement of cells/chromosomes and example of movement;
b. movement of flagellum/cilium;
c. endocytosis/exocytosis;
d. detachment of myosin heads from actin filaments / myosin heads change their angle/become cocked;
e. active transport and example of use of active transport;
f. anabolic reactions / polymerization example / example of synthesizing macromolecules;
g. generation of heat and to provide optimum temperature for enzyme activity / in homeostasis / to maintain body temperature;
h. phosphorylation of substrates in glycolysis;
i. phosphorylation of substrates in photosynthesis light-independent reaction/Calvin cycle;

For a. accept descriptions of cells (e.g. amoeboid phagocyte moving to site of infection) or chromosomes (e.g. anaphase, chromosomes moving to opposite poles).
For d. ignore 'muscle contraction'.
For e. E.g. sodium-potassium pump (in neurons) / maintaining resting potential in neurons / generation of root pressure / villus epithelial cells / selective reabsorption in kidney.
For e. do not accept transport of large molecules as example.
For f. accept examples such as DNA replication / transcription / translation / and other examples of formation of macromolecules.
For h. accept phosphorylation of glucose (to glucose-6-phosphate) or phosphorylation of fructose-6-phosphate (to fructose 1,6-biphosphate).
For i. accept formation of triose phosphate and formation of ribulose bisphosphate (regeneration of RuBP).

a. NAD/FAD carries/is reduced by gaining «two» H «atoms»/«two» electrons
b. reduced NAD produced in glycolysis/link reaction/Krebs cycle
c. reduced NAD/FAD delivers electrons/hydrogen «atoms» to ETC
d. ETC is in mitochondrial inner membrane/cristae
e. electrons release energy as they flow along the chain/from carrier to carrier
f. electrons from ETC accepted by oxygen/oxygen is the final electron acceptor
g. proteins in the inner mitochondrial membrane/electron carriers act as proton pumps
h. protons pumped into intermembrane space/proton gradient across inner mitochondrial membrane/proton concentration higher in intermembrane space than in matrix
i. energy «from electrons» used to pump protons into intermembrane space/generate a proton gradient / high $\mathrm{H}^{+}$concentration is a store of «potential» energy
j. ATP synthase in inner mitochondrial membrane/cristae
k. energy released as protons pass down the gradient/through ATP synthase
I. ATP synthase converts ADP to ATP/phosphorylates ADP
m. oxidative phosphorylation «is ATP production using energy from oxidizing foods»

a. energy released by oxidation reactions;

b. more carbon/hydrogen (per gram) in triglycerides (than glucose)

OR

more C-C/C-H bonds (per gram) in triglycerides (than glucose);

c. triglycerides in less oxidized/more reduced state/ have less oxygen (per gram than glucose);

d. more acetyl CoA formed (per gram) from triglycerides (than glucose)

OR

more $\mathrm{NADH}_{2} /$ reduced NAD (per gram) from triglycerides (than glucose);

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