Exam 4 Misc

Question 1

Two backup systems in the liver to deal with Ammonia.

Answer 1

Periportal and Perivenous both located in the acinus

Question 2

Periportal system

Answer 2

glutaminase releases NH3 from glutamine to make urea via the cycle
glutamate dehydrogenase releases NH3 from glutamate to create a-ketoglutarate

Question 3

Perivenous system

Answer 3

glutamine synthetase scavenges excess NH3 to make glutamate and a-ketoglutate which are taken to the kidneys for deamination

Question 4

Transamination

Answer 4

Amino Acid 1 + Keto Acid 2 –> Amino Acid 2 + Keto Acid 1

Question 5

Deamination

Answer 5

Amino acid –> keto acid + NH3 (via dehydratase)

Question 6

General Catabolic Site for amino acids

Answer 6

Most in liver and kidney with the branched chains in the muscle

Question 7

Cause of Maple Syrup Urine Disease

Answer 7

Deficiency in the Branched Chain a-keto acid Dehydrogenase Complex

Question 8

Cause of Phenylketonuria

Answer 8

Deficiency in the enzyme Phenylalanine Hydroxylase. Without it, Phenylalanine can’t be broken down to Tyrosine. It builds up and becomes phenylpyruvate / phenylketone

Question 9

Catecholamines are derived from which amino acid?

Answer 9

Tyrosine

Question 10

Which amino acid makes niacin and where?

Answer 10

Tryptophan in the liver

Question 11

Which amino acid makes taurine?

Answer 11

Cysteine

Question 12

Which amino acid makes Cysteine?

Answer 12

Methionine

Question 13

Which amino acid is considered semi-essential and why?

Answer 13

Cysteine because infants and those with certain metabolic diseases or malabsorbtion syndrome are unable to get it

Question 14

Which Amino Acids do not undergo transamination?

Answer 14

Lysine and Threonine

Question 15

What happens physically when you do not consume enough essential amino acids?

Answer 15

Muscle degradation (body breaks down muscle to get protein), decreased immune response, weakness, fatigue, and changes to the texture of your skin and hair

Question 16

What happens mentally when you do not consume enough essential amino acids?

Answer 16

Lysine has an effect on serotonin and stress.

Question 17

Which tissues can use ketone bodies?

Answer 17

The same tissues that can use fatty acids (heart, brain and not liver)

Question 18

Which amino acids are important to transfer amino acids from the muscle to the liver?

Answer 18

Glutamine and Alanine

Question 19

Creatine use in exercise vs rest

Answer 19

During exercise phosphocreatine provides a way to replenish ATP (substrate level phosphorylation) while at rest the phosphocreatine is degraded to creatine and excreted.

Question 20

Rate limiting enzyme of the urea cycle

Answer 20

Carbamoyl Phosphate Synthetase

Question 21

6 Primary functions of proteins

Answer 21

Hormones, enzymes, antibodies, Transportation and storage or molecules, energy, repair

Question 22

Insulin Function

Answer 22

GI hormones amplify pancreatic response to glucose. Stimulates glycolysis, glycogenesis, lipogenesis, protein synthesis. Affects glucose uptake in muscle and liver.

Question 23

Glucagon

Answer 23

Activates liver lipases and glycogenolysis

Question 24

Catecholamines

Answer 24

Increase blood glucose by decreasing glucose uptake of muscles. Epi / Norepi

Question 25

Glucocorticouds

Answer 25

Important for stimulating gluconeogenesis. Cause degradation to make amino acids available. Adrenal cortex

Question 26

Phases of fed / fasting

Answer 26

Fed / Post Absorption: Glycogenolysis Fasting: Gluconeogenesis Starvation: Gluconeogenesis / Ketosis

Question 27

When can ketones not be made?

Answer 27

When insulin is high

Question 28

Which amino acids can become glucose?

Answer 28

Ala, Gly, Cys, Ser. Must first be able to be converted to pyruvic acid

Question 29

Which amino acids can become lipids?

Answer 29

Ile, Leu, Trp, Lys, Phe, Tyr. Must first be able to be converted to Acetyl CoA