Metabolic Flux

Question 1

The allosteric modulation binds ___.

Answer 1

Noncovalently

Question 2

Protein kinase is a ___ reaction.

Answer 2

Transferase reaction

Question 3

Phosphoprotein phosphatase is a ___ reaction.

Answer 3

Hydrolysis reaction

Question 4

Effectors that inhibit activity are termed?

Answer 4

Negative effectors

Question 5

Effectors that increase enzyme activity are called?

Answer 5

Positive effectors

Question 6

Is Glucose-6-phosphate a positive or negative effector?

Answer 6

Negative effector

Question 7

Is glucose-6-phosphate a homotropic effect?

Answer 7

Yes; immediate substrate or product of the enzyme which serves as an allosteric effector.

Question 8

is fructose 1,6-bisphosphate a positive or negative effector?

Answer 8

Positive

Question 9

Is fructose 1,6-bisphosphate a heterotropic effector?

Answer 9

Yes; an allosteric effector who is neither the immediate substrate or product of the enzyme

Question 10

ATP is a ______ effector.

Answer 10

Homotropic effector

Question 11

Covalently modifiable enzymes will undergo the addition or removal of phosphate groups from specific ___, ___ or ___ residues of the enzyme.

Answer 11

Serine threonine or tyrosine

Question 12

The majority of enzymes in any given cell are ___ allosterically or covalently modifiable.

Answer 12

Neither

Question 13

HExokinase is inhibited by?

Answer 13

Glucose 6-phosphate

Question 14

What inhibits PFK? (2)

Answer 14

ATP, Citrate

Question 15

What activates PFK?

Answer 15

ADP, AMP, Fructose2,6-bisphosphate

Question 16

What inhibits Pyruvate Kinase?

Answer 16

ATP

Question 17

What Activates Pyruvate kinase?

Answer 17

Fuructose 1,6-bisphosphatate

Question 18

Is Glucokinase inhibited by glucose 6-phosphate?

Answer 18

No!

Question 19

Is pyruvate kinase covalently modifiable?

Answer 19

Yes!

Question 20

Via the Law of Mass action, high concentrations of NADH and Acetyl CoA drive the E3 and E2 mechanisms____.

Answer 20

Backward

Question 21

When E1 is phosphorylated, it is on or off?

Answer 21

Off

Question 22

When E1 is dephosphorylated, it is on or off?

Answer 22

On

Question 23

Pyruvate dehydrogenase phosphatase will turn on or off E1?

Answer 23

On

Question 24

Acetyl-CoA and NADH will turn E1 on or off?

Answer 24

Off

Question 25

Covalent regulations are under ___ control

Answer 25

Hormonal (Insulin, glucagon, epinephrine and norepinephrine)

Question 26

Phosphodiesterase can quickly terminated what?

Answer 26

cAMP (2nd messenger)

Question 27

The ___ messenger initiates an amplification cascase

Answer 27

First

Question 28

Caffeine can inhibit ___.

Answer 28

Phosphodiesterase

Question 29

Glycogen phosphorylase can be caused by what two hormones?

Answer 29

Glucagon(liver) and Epinephrine (muscle and liver)

Question 30

When insuline is present, level of cAMP___.

Answer 30

Decrease

Question 31

Transcription factors are?

Answer 31

Nuclear proteins, when activated bind to a DNA's response element and activate or repress the transcription of that gene. Leading to increased or decreased synthesis of the encoded protein.

Question 32

How long is the half-life of a protein?

Answer 32

Between 3 minutes and 20 hours

Question 33

What is the half-life of insulin?

Answer 33

5-7 minutes

Question 34

Ubituitination is a tag for what?

Answer 34

Destruction of defective protein. (Recycles garbage, makes amino acid)