Cellular respiration

Question 1

in citric acid cycle, what happens to NAD+

Answer 1

electrons are passed to it and its reduced to NADH

Question 2

in citric acid cycle, what happens to FAD

Answer 2

electrons are passed to it, reduced to FADH2

Question 3

is ATP produced or used in citric acid cycle

Answer 3

produced

Question 4

how many turns of citric acid cycle does complete oxidation of glucose require

Answer 4

2

Question 5

Overall, 1 turn of citric acid cycle/glucose

Answer 5

1 ATP
3 NADH
1 FADH2
2 CO2

Question 6

total production/glucose (glycolysis + Krebs)

Answer 6

4 ATP
10 NADH
2 FADH2
6 CO2

Question 7

what are the 2 mobile e- carriers in ETC

Answer 7

coenzyme Q and cytochrome Q

Question 8

what does complex II do

Answer 8

shuttles e- from FADH2 to coenzyme Q

Question 9

what are the 3 functions of ETC

Answer 9

• e- transferred from carrier to carrier
• e- drop in free E as they move from carrier to carrier: E released to pump H+ into intermb space
• ETC generates H+ gradient: used to produce ATP by chemiosmosis

Question 10

from who does complex I receive electrons

Answer 10

NADH

Question 11

what does coenzyme Q receive e- from

Answer 11

complex I or FADH2 (via complex II)

Question 12

where does complex III receive its e-s from

Answer 12

coenzyme Q

Question 13

what does complex III contain

Answer 13

cytochromes

Question 14

what does cytochrome c receive its e- from

Answer 14

complex III

Question 15

where does complex IV get its e-s from

Answer 15

cytochrome C

Question 16

does complex IV contain cytochromes

Answer 16

yes

Question 17

what does complex IV do other than pumping H+

Answer 17

transfers e- to O2 producing H2O

Question 18

what enzyme catalyzes ADP+ Pi -> ATP

Answer 18

ATP synthase

Question 19

what happens to H+ once it passes through ATP synthase

Answer 19

diffuses back into mitochondrial matrix

Question 20

in mitochondria, what has a higher H+ concentration, intermb space or matrix

Answer 20

intermb space

Question 21

where do the 6 CO2 produced/ glucose come from

Answer 21

• 2 CO2 from pyruvate oxidation
• 4 CO2 from CA cycle

Question 22

where do the 32 ATP produced/ glucose come from

Answer 22

4 ATP:
- glycolysis (2 ATP)
- citric acid cycle (2 ATP)
(both substrate level phosphorylation)

28 ATP
- NADH = 25 ATP (2.5 ATP/NADH) so 10 NADH
- FADH2= 3 ATP (1 FADH2=1.5 ATP) so 2 FADH2

Question 23

what other organic molecules can CR extract energy from

Answer 23

protein, fats

Question 24

how does cellular respiration work from protein

Answer 24

protein –(hydrolysis)–> A.A.—-> pyruvate, Acetyl CoA or a-ketoglutarate

(NH3 excreted in form of ammonia/uria in process called deamination)

Question 25

how does cellular respiration work from fats

Answer 25

fats—-(hydrolysis)—> glycerol—-> G3P
and
fats—-(hydrolysis)—> fatty acids—-> Acetyl-CoA

Question 26

oxidation of 1g of fat produces ___ as much ATP as 1 g of carbs

Answer 26

2x

Question 27

why do cells regulate rates

Answer 27

responding to metabolic needs

Question 28

what is phosphofructokinase allosterically regulated by

Answer 28

ATP and AMP

Question 29

when there is high ATP, what happens to phosphofructokinase

Answer 29

ATP inhibits

Question 30

when there is low ATP, what happens to phosphofructokinase

Answer 30

AMP activates (bc low ATP=high ADP/AMP)

Question 31

when there is high citrate, what happens to phosphofructokinase

Answer 31

inhibited by citrate

Question 32

does fermentation need O2

Answer 32

no

Question 33

what is fermentation

Answer 33

anaerobic catabolism of organic molecules (production of ATP without O2)

Question 34

how does fermentation produce ATP w/o oxygen

Answer 34

ATP produced by glycolysis only
2ATP/glucose

Question 35

what are the 2 types of fermentation

Answer 35

1. alcohol fermentation
2. lactic acid fermentation

Question 36

for alcohol fermentation, what 2 steps are used to convert pyruvate to ethanol

Answer 36

1. glycolysis
   glucose—-> 2 pyruvate ——> 2 acetaldehyde + 2 CO2
   PRODUCTS: 2 ATP, 2 NAD+, 2 CO2, 2 acetaldehyde
2. 2 acetaldehyde —-> 2 ethanol
   PRODUCTS: 2 ethanol, 2 NAD+

Question 37

how does lactic acid fermentation turn glucose to lactate

Answer 37

glucose ——> 2 pyruvate ——> 2 lactate

PRODUCTS: 2 ATP, 2 NADH (GET USED TO MAKE 2 NAD+)