B vitamins Flashcards

1
Q

T/F: does B1 work with B2, B3, and B5 in the pyruvate dehydrogenase reaction?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

T/F: B-vitamins may use phosphatases to help facilitate absorption?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

T/F: a thiamin deficiency can adversely affect nerve conduction through decreased production of acetylcholine?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What vitamin coenzymes forms are based on a nucleotide structure?

A

NADPH, FADH2, FMN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What vitamin coenzymes are needed in the Heme synthesis pathway?

A

B6, B7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

if a tryptophan load test was done on a patient who was deficient in B6, what would happen to the production of NAD+ and excretion of xanthurenic acid?

A

decreased production on NAD+

Increased excretion of xanthurenic acid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

B6 is used to make all of the following NTs except:
a. GABA
b. Serotonin
c. Dopamine
D. acetylcholine

A

B6 does not make acetylcholine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

IF (intrinsic factor) : what is the role of B12?

A

IF is bound to B12 and internalized via receptor-mediated endocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

All citric acid cycle dehydrogenases produce NADH except for?

A

succinate dehydrogenase which produces FADH2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the physiologival effects of nicotinic acid from B3?

A

causes vasodilatory prostaglandin release, responsible for the niacin flush

causes enhanced fibrinolysis to help prevent clot buildup and improve blood flow

improves lipid profile: decrease VLDL/ DL and increase HDL

increased histamine release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what enzyme blocks the production of vascodilatory prostaglandins in the niacin flush?

A

COX (cyclooxygenase).

so to prevent this use NSAIDs that inhibit COX for example aspirin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how can nicotinic acid be applied to Raynaud’s phenomenon?

A

vasodilatory mechanism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

why would nicotinic acid be harmful for someone with peptide ulcer disease?

A

NAC can cause increased histamine release, which mediates inflammation and vasodilations, increased histamine released makes symptoms worse because it stimulates gastric acid secretion irritating the ulcerated mucosa and increasing pain or bleeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

why would nicotinic acid potentially lead to hyperglycemia?

A

decreased phosphorylation of glucose by glucokinase which regulates blood glucose by phosphorylation in the liver. With decreased activity there is less glucose uptake and storage in liver, leaving more in bloodstream.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

to avoid all of these side effects of nictonic acid, what is an alternative?

A

nicotinamide!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

one coenyzme form of B12 is Methylcobalamin that catalyzes the methionine synthase rxn to make methionine, what would a deficiency here cause?

A

Methyl folate trap

17
Q

what is a symptom that a b12 deficiency does NOT share with B9?

A

neurological deficit

18
Q

how is B12 uptake facilitated in enterocytes and also in tissues?

A

receptor mediated endocytosis

19
Q

what would you expect to see affected by a deficiency in B1 Thiamin?

A

CNS and/or cardiovascular system

20
Q
A