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Flashcards in Exam 3 Deck (28):
1

During protein synthesis, how many phosphoanhydride bonds are hydrolyzed (broken) for each amino acid in a protein?

4

2

Which molecule is involved with the oxidation of glucose, synthesis of fatty acids and oxidation of fatty acids?

acetyl-CoA

3

What represents the net products of glycolysis from one molecule of glucose?

2 pyruvate, 2 NADH, 2 ATP

4

What is the name for the process that produces ATP from ADP in glycolysis?

substrate-level phosphorylation

5

Under anaerobic conditions in skeletal muscle, pyruvate is converted into

lactate

6

What is an inhibitor of pyruvate dehydrogenase?

NADH

7

What transport system moves activated fatty acids (acyl-CoA) from the cytosol to the mitochondrial matrix?

Carnitine shuttle

8

Each round of B-oxidation of a saturated fatty acyl-CoA produces

1 NADH, 1 QH2, 1 acetyl-CoA

9

The activation of acetyl-CoA for fatty acid synthesis is achieved by converting the acetyl-CoA into

malonyl-CoA

10

What molecule is able to move across the mitochondrial membrane and is thus used to "transfer" acetyl-CoA from the mitochondria to the cytosol?

citrate

11

Under anaerobic conditions, _______ is produced in the muscle and is then used by the liver for _____.

lactate
gluconeogenesis

12

How does insulin cause an increase in the rate of glucose transport into cells?

recruits glucose transporters from intracellular vesicles to the cell membrane

13

What hormone is most likely responsible for the body weight set-point?

leptin

14

What aspect of brown adipose tissue is responsible for its ability to generate heat?

the uncoupling protein thermogenin allows fatty acid oxidation without ATP production

15

When a reaction is at equilibrium, the DeltaG is equal to

0

16

The steps in glycolysis that are different than those in gluconeogenesis are catalyzed by these enzymes

pyruvate kinase, phosphofructokinase, hexokinase

17

To mobilize glucose from glycogen for energy, the activity of two enzymes, _____ and _____ are carefully regulated by kinases and phosphatases to ensure sufficient energy is available for use.

glycogen phosphorylase and glycogen synthase

18

Inhibited by NADH and Succinyl-CoA

Alpha-ketoglutarate dehydrogenase complex

19

Inhibited by Succinyl-CoA and ATP

Citrate synthase

20

Stimulated by AMP and CoA

Pyruvate dehydrogenase complex

21

Stimulated by ADP; inhibited by ATP

Isocitrate dehydrogenase

22

Stimulated by Citrate

Acetyl-CoA carboxylase

23

Lactate released from muscle converted back to glucose in liver. What is the cost of ATP of this cycle?

4 ATP since 2 ATP are generated in glycolysis.
Gluconeogenesis is 6 ATP.

24

What is one of the major hormones that regulates gluconeogenesis?

Insulin. It decreases transcription of genes coding for certain gluconeogenic enzymes.

25

For which genes would you expect insulin to suppress transcription?

Gluconeogenic enzymes:
G6P
PEPCK
Fructose,1,6-biphosphatase
Pyruvate carboxylase

26

Which compound could be involved in a reaction coupled to the synthesis of ATP from ADP + Pi?

Reactions involving phoshphoenolypyruvate, 1,3-bisphosphoglycerate, and phosphocreatine

27

ADP stimulates the activity of phosphofructokinase, yet it is a _____ of the reaction not a ______

product
not a reactant

28

Yeast grow under anaerobic conditions and can convert pyruvate to alcohol in a process called

fermentation