Protein 4

Question 1

What is the fate of glutamine synthesized by tissues besides intestine (mostly muscle)

Answer 1

taken up by intestinal cells

Question 2

What is the purpose of glutamine in muscle

Answer 2

to transport ammonia

Question 3

What is the purpose of glutamine in liver during fed state

Answer 3

Liver: fed state – urea cycle

Question 4

What is the purpose of glutamine in liver during fasted state

Answer 4

glutamine is released into blood for pick up by kidneys for maintenance of acid base balance

Question 5

What is the purpose of glutamine in kidneys

Answer 5

breaks down glutamine to generate ammonia + glutamate

Question 6

90% of glutamate from diet is used by the?

Answer 6

Intestine

Question 7

How can glutamate be synthesized

Answer 7

from glutamine by glutaminase (this reaction also yields ammonia)

Question 8

Transamination from glutamate to pyruvate yields

Answer 8

α-ketoglutarate and alanine

Question 9

Synthesis of glutathione occurs when?

Answer 9

Glutamate when combined to glycine and cysteine

Question 10

The majority of proline synthesis comes from

Answer 10

intestinal metabolism of glutamate

Question 11

How is Ornithine formed

Answer 11

Glutamate Combines with aspartate

Question 12

40% of dietary arginine is oxidized in the intestine with formation of

Answer 12

citrulline and urea

Question 13

–Citrulline synthesized in the intestine is picked up by?

For what?

Answer 13

the kidneys

for arginine synthesis

Question 14

How does Arginine become conditionally essential

Answer 14

Intestinal injury may impair production of arginine by the kidneys

Question 15

The liver takes up citrulline for ?

Answer 15

urea synthesis

Question 16

When are glutamine and alanine released from muscle

Answer 16

Fasted state

Question 17

How do the muscles produce glucose

Answer 17

Alanine is released by the muscle and picked up by the liver.
Liver breaks alanine down into pyruvate which can be used for gluconogenesis

Question 18

What organ has very low activity of Branched chain aminotransferaces

Answer 18

Liver

Question 19

Alpha-ketoacids from muscle are further decarboxylated by

Answer 19

branched-chain alpha keto acid dehydrogenase (BCKAD)

Question 20

Decreased activity of BCKAD leads to

Answer 20

maple syrup urine disease

Question 21

What’s important about leucine

Answer 21

Only ketogenic

Preferred by muscle as source of energy

Question 22

Valine is glucogenic/ketogenic or both

Answer 22

Glucogenic

Question 23

Isoleucine is glucogenic/ketogenic or both

Answer 23

Both

Question 24

Leucine metabolism generates HMB which is important for?

Answer 24

HMG-CoA synthesis (which is important for cholesterol synthesis)

Question 25

Leucine yields

Answer 25

Acetyl CoA and acetoacetate

Question 26

an indicator of protein breakdown in muscle as well as other tissues where actin is found is?

Answer 26

Urinary 3-methylhistidine

Question 27

What is the fate of 3-methylhistidine

Answer 27

Cannot be reused for protein synthesis so its fate is to be excreted

Question 28

Where is actin found besides muscle

Answer 28

Actin is also present in platelets and intestine

Question 29

What is the Role of glutamine and glutamate in maintenance of acid base balance

Answer 29

In acidotic conditions glutamine and glutamate are deaminated in the kidneys yielding 2 ammonias

Question 30

Glycine role in kidneys

Answer 30

Can also be deamination to form ammonia

Question 31

3 reasons Why is glutamine important for intestines

Answer 31

–Serves as the primary source of energy
–Prevents atrophy of gut mucosa and bacterial translocation
–Needed for mucin production