quiz 7

Question 1

for step 0 of cac
substrate:
product:
enzyme

Answer 1

pyruvate, CoA, NAD+
NADH, acetyl CoA
pyruvate dehydrogenase complex
also uses TPP, lipoate, FAD

Question 2

how is pyruvate transported to the mitochondria

Answer 2

tramsmembrane transporter proteins

Question 3

what does a low EC mean

Answer 3

pyruvate is metabolized by pyruvate dehydrogenase and acetyl CoA and CO2 is formed

Question 4

what are the 5 enzymes needed for step 0

Answer 4

NAD+/NADH
FAD/FADH2
CoA
TPP
a-lipoic acid

Question 5

describe NAD+

Answer 5

derived from niacin (B3)
transfers 2e- at once leaving H-
pellagra is a B3 deficiency

Question 6

describe FAD

Answer 6

derived from riboflavin (B2)
reduced to FADH2 by transferring 2e-
transfers one e- at a time when
cheilosis is a B2 deficiency

Question 7

describe CoA

Answer 7

derived from panthothenic acid (B5)
cofactor for fatty acid, acetyl choline, heme, cholesterol
required for energy conversion in cac
a deficiency is rare

Question 8

how does CoA cross the membrane

Answer 8

CoA is degraded by enzymes to B5
crosses membrane and reverts to CoA
ATP and cys are added

Question 9

describe TPP

Answer 9

derived from thiamine (B1)
absorbed in gut and phosphorylated
beriberi is a B1 deficiency

Question 10

describe a-lipoic acid

Answer 10

synthesized in plants and animals (esp broccoli, liver, spinach, tomatoes)
provides disulphide for redox rxn
receives acetyl from TPP and transfers it to CoA

Question 11

describe rxn 0

Answer 11

occurs before cycle begins
irreversible
pyruvate changes to acetyl CoA

Question 12

define oxidation

Answer 12

loss of e-

Question 13

define reduction

Answer 13

gain of e-

Question 14

define oxidant

Answer 14

oxidize other molecules, accepts e-, reduced

Question 15

define reductant

Answer 15

reduce other molecules
donates e-
oxidized

Question 16

define coupled rxn

Answer 16

combined 2 half rxns with a common intermediate

Question 17

standard reduction potential

Answer 17

Question 18

free energy

Answer 18

Question 19

which steps are regulated

Answer 19

0, 1, 3, and 4

Question 20

what is the net rxn for CAC

Answer 20

acetyl CoA + 3NAD+ + FAD + GDP + Pi + 2H2O —-> CoA + 2CO2 + 3NADH + 3H+ + FADH2 + GTP

Question 21

step 1
substrate:
product:
enzyme

Answer 21

acetyl CoA, oxaloacetate, H2O
citrate, CoA
citrate synthase

Question 22

step 2
substrate:
product:
enzyme

Answer 22

citrate
isocitrate
aconistase

Question 23

step 3
substrate:
product:
enzyme

Answer 23

isocitrate, NAD+
a-ketogluterate, NADH, CO2
isocitrate dehydrogenase

Question 24

step 4
substrate:
product:
enzyme

Answer 24

a-ketogluterate, NAD+, CoA-SH
succinyl-CoA, NADH, CO2
a-ketogluterate dehydrogenase

Question 25

step 5 substrate: product: enzyme

Answer 25

succinyl-CoA, Pi, GDP succinate, CoA, GTP succinyl-CoA synthetase

Question 26

step 6 substrate: product: enzyme

Answer 26

succinate, FAD fumarate, FADH2 succinate dehydrogenase

Question 27

step 7 substrate: product: enzyme

Answer 27

fumarate, H2O malate fumerase

Question 28

step 8 substrate: product: enzyme

Answer 28

malate, NAD+ oxaloacetate, NADH+H+ malate dehydrogenase

Question 29

what is the regulation of pyruvate dehydrogenase

Answer 29

regulated by energy charge

Question 30

what is citric acid used for

Answer 30

commercial food preservation

Question 31

how is redox power generated

Answer 31

oxidizing acetyl CoA and reducing NAD and FAD

Question 32

how many intermediates are shared by other pathways

Answer 32

5

Question 34

where does the majority of ATP come from

Answer 34

oxidative phosphorylation

Question 35

what is oxidative phosphorylation powered by

Answer 35

chemiosmosis

Question 36

define chemiosmosis

Answer 36

chemical osmosis pumps protons

Question 37

define crista

Answer 37

folds of the inner membrane where ATP synthase occurs

Question 38

define matrix

Answer 38

aqueous interior of mitochondria where CAC occurs

Question 39

how is ATP produced

Answer 39

when H+ flows through ATP synthase

Question 40

describe slow muscle twitches

Answer 40

aerobic energy long periods of more mitochondria

Question 41

describe fast muscle twitches

Answer 41

aerobic energy short bursts less mitochondria

Question 42

describe chloroplast in the plant cells

Answer 42

analogous to mitochondria uses light energy circuit is flipped

Question 43

what is potential energy modified to

Answer 43

work

Question 44

define ATP synthase

Answer 44

motor that preforms work

Question 45

define uncoupler

Answer 45

circuit continues but via an alternate route

Question 46

define inhibitor

Answer 46

blocks circuit and stops the floe

Question 47

what does uncoupleS oxidative phosphorylation do

Answer 47

allows H+ to flow without ATP synthase

Question 48

what does a low pH cause? a high pH?

Answer 48

pronation depreciation

Question 49

define oligomycin

Answer 49

blocks protein circuit creates a high pH in matrix causes cellular death