topic 5.2.2: respiration

Question 1

where does glycolysis occur

Answer 1

cytoplasm

Question 2

what is the function of glycolysis

Answer 2

glucose is split into 2 pyruvates. ATP and RNAD produced

Question 3

describe the first stage of glycolysis

Answer 3

PHOSPHORYLATION
2 phosphates released from ATP and attached to a glucose molecule to form hexose bisphosphate

Question 4

describe the second stage of glycolysis

Answer 4

LYSIS
this destabilises the molecule causing it to split into 2 3C sugars

Question 5

describe the third stage of glycolysis

Answer 5

PHOSPHORYLATION
another phosphate group added to each from free inorganic phosphate ions in cytoplasm

Question 6

describe the fourth stage of glycolysis

Answer 6

DEHYDROGENATION
formation of ATP
the 2 mols are then oxidised to form 2 pyruvates. NAD accept removed H+ so are reduced. 4 ATP mols formed

Question 7

what is substrate level phosphorylation

Answer 7

the formation of ATP with no ETC

Question 8

where does the link reaction occur

Answer 8

matrix

Question 9

what happens in the link reaction

Answer 9

OXIDATIVE DECARBOXYLATION
pyruvate enters matrix by AT via carrier proteins
then undergoes OD (H+ and CO2 removed)
H+ accepted by NAD
2C acetyl group is bound to coenzyme A
acetyl coA used to deliver to next stage

Question 10

where does the krebs cycle occur

Answer 10

matrix

Question 11

what is the purpose of the krebs cycle

Answer 11

generates reduced coenzymes and ATP

Question 12

what happens in the krebs cycle

Answer 12

coA released
acetyl combines with oxaloacetate
6C citrate formed
decarboxylation to produce 2CO2
ADP phosphorylated
FAD reduced
3NAD reduced
4C oxaloacetate produced

Question 13

where are the electron transport chains

Answer 13

membranes of cristae

Question 14

what is chemiosmosis

Answer 14

diffusion of protons from a region of high to low concentration through a partially permeable membrane which releases energy

Question 15

what is the final stage of respiration

Answer 15

oxidative phosphorylation

Question 16

describe the electron transport chain

Answer 16

high energy electrons move along carriers which releases energy
protons pumped across membrane, h+ stay
protons diffuse back across through atp synthase channels
at the end electrons combine with h+ and oxygen to form water (final electron acceptor)

Question 17

what are the overall products of respiration

Answer 17

28 atp, 6 h2o

Question 18

what happens in anaerobic respiration

Answer 18

pyruvate is reduced to form ethanol and carbon dioxide in plants or lactate in mammals by gaining h+ from red nad
nad is reused in glycolysis

Question 19

how many atp produced per glucose in anaerobic respiration

Answer 19

2

Question 20

how is respiratory quotient calculated

Answer 20

co2 produced/ oxygen consumed

Question 21

what is the rq for glucose

Answer 21

1

Question 22

what is the rq for fats

Answer 22

0.7

Question 23

what is the rq for proteins

Answer 23

0.9