Nitrogen Metab and Integration of Metabolism

Question 1

How much is the protein turnover per day

Answer 1

300-400g

Question 2

Catabolism of amino acids turns them into this final product

Answer 2

A- keto acid

Question 3

The first phase of amino acid catabolism involves transferring their amino group to a-ketoglutarate forming this amino acid

Answer 3

Glutamate

Question 4

Enzyme in the transamination step of the 1st phase of amino acid catabolism

Answer 4

Aminotransferase

Question 5

Coenzyme of aminotransferase in Transamination

Answer 5

B6 pyridoxal phosphate

Question 6

In the 2nd step of the 1st phase of AA catabolism, glutamate is oxidatively deaminated to release free ammonia in which organs

Answer 6

Liver and kidney

Question 7

What is the enzyme involved in the oxidative deamination step of AA catabolism?

Answer 7

Glutamate dehydrogenase

Question 8

Transport of ammonia to peripheral tissues is through this amino acid

Answer 8

Glutamine through glutamine synthase

Question 9

Glutamine can also be transported in the blood and deaminated to release ammonia in these organs

Answer 9

Liver and kidney through glutaminase

Question 10

Exceptions to transamination of amino acids to glutamate

Answer 10

Lysine
Threonine
Proline
Hydroxyproline

Question 11

Transport of ammonia in the muscle is possible when pyruvate is transaminated to what amino acid

Answer 11

Alanine

Question 12

Excretion of excess nitrogen in telostean fish which excrete highly toxic ammonia

Answer 12

Ammonotelic

Question 13

Excess nitrogen excretion in birds which secrete uric acid as semisolid Guano

Answer 13

Uricotelic

Question 14

Excess nitrogen excretion in land animals who excrete it as urea

Answer 14

Ureotelic

Question 15

In what organ does the urea cycle occur?

Answer 15

Liver only

Question 16

Where in the cell does urea cycle occur?

Answer 16

Both mitochondria and cytosol

Question 17

Substrates of Urea cycle

Answer 17

NH3
Aspartate
CO2

Question 18

What is the rate limiting step of urea cycle?

Answer 18

NH3 + CO2 to carbamoyl phosphate through carbamoyl phosphate synthetase 1

Question 19

Allosteric activator of carbamoyl phosphate synthetase 1

Answer 19

N- acetylglutamate

Question 20

Most common enzyme deficiency in Urea cycle

Answer 20

Ornithine transcarbamoylase

Question 21

Link of urea cycle to Krebs cycle

Answer 21

Fumarate

Question 22

1 mol of urea needs how many ATP?

Answer 22

3 mol of ATP

but 4 high energy bonds (AMP)

Question 23

Urea can be excreted through

Answer 23

Urine

Intestines where bacteria converts it to CO2 and NH3

Question 24

This disease has a direct neurotoxic effect on the CNS

Tremors, slurring of speech, vomiting, BOV, cerebral edema

Answer 24

Hyperammonemia

NH3–a ketoglutarate–glutamate (excitatory)

Question 25

Most severe form of hereditary hyperammonemia

Answer 25

Carbamoyl phosphate synthetase 1 deficiency

Question 26

Treatment for hereditary hyperammonemia that binds to glutamine and excreted as phenylglutamine

Answer 26

Phenylbutyrate

Question 27

Purely ketogenic amino acids (may be converted to acetyl CoA of acetoacetyl CoA)

Answer 27

Ketong-genic Lysine Leucine

Question 28

Amino acids that are both ketogenic and glucogenic

Answer 28

Try Philippine Islands TY Tryptophan Phenylalanine Isoleucine Tyrosine

Question 29

NO, creatine and polyamines is a derivative of which amino acid

Answer 29

Argggh NO Creating here Arginine

Question 30

Coenzyme A, taurine and glutathione is a derivative of which amino acid

Answer 30

TAU pa RINE ba si Christeine, ang cO-A ng puti kaka-Gluta Taurine Coenzyme A Glutathione

Question 31

Products of this amino acid include heme, purines, creatine, glutathione

Answer 31

Glycine

Question 32

Thymine, purine and sphingosine comes from this amino acid

Answer 32

Serine

Question 33

Cofactor of phenylalanine hydroxylase that may be deficient in phenylketonuria

Answer 33

Tetrahydrobiopterin

Question 34

This phenylketone gives the characteristic odor of urine in phenylketonuria

Answer 34

Phenylacetate

Question 35

Congenital deficiency in homogentisate oxidase that leads to homogentisic acid accumulation Urine turns black upon standing, arthralgia, dark connective tissue

Answer 35

Alkaptonuria

Question 36

Homocystinuria happens due to defect in the degradation of this amino acid

Answer 36

Methionine

Question 37

Ectopis lentis (downward) Osteoporosis MR thrombi formation, MI, stroke in children and adults

Answer 37

Homocystinuria

Question 38

Treatment for homocystinuria

Answer 38

Vitamin B6 B12 and folate

Question 39

Cystinuria is an inherited defect of renal tubular amino acid transporter for which amino acids in the PCT of the kidneys

Answer 39

``` COLA Cystine Ornithine Lysine Arginine ```

Question 40

Cystinuria can precipitate formation of ______ in the kidney

Answer 40

Staghorn calculi

Question 41

This drug is used to treat cystinuria to alkalinize the urine

Answer 41

Acetazolamide

Question 42

Methylmalonyl CoA mutase deficiency can cause a defect in the conversion of methylmalonyl to succinyl CoA Stroke, seizures, enceph at 1 mo to 1 yr old And involves metabolism of these amino acids

Answer 42

``` TIM V Threonine Isoleucine Methionine Valine ```

Question 43

Maple syrup urine disease is due to blocked degradation of branched chain amino acids because of deficiency in this enzyme

Answer 43

A-ketoacid dehydrogenase

Question 44

These are cyclic compounds formed by the linkage of 4 pyrrole rings through methyne bridges

Answer 44

Porphyrins

Question 45

What is the rate limiting step of heme synthesis

Answer 45

Formation of d-ALA from glycine and succinyl CoA through ALA synthase

Question 46

Cofactor of ALA synthase in the rate limiting step of heme synthesis

Answer 46

Pyridoxine

Question 47

Formation of porphobilinogen is inhibited by

Answer 47

Heavy metal ions that replace zinc

Question 48

What enzyme catalyzes the formation of heme from protoporphyrin IX?

Answer 48

Ferrochelatase

Question 49

In heme degradation, bilirubin is conjugated to 2 molecules of glucoronic acid for excretion. This enzyme is deficient in Crigler Najjar and Gilbert syndrome

Answer 49

Bilirubin glucuronyltransferase

Question 50

Bilirubin in stool is called

Answer 50

Stercobilin

Question 51

Bilirubin in urine is called

Answer 51

Urobilin

Question 52

Bilirubin in the intestines is called

Answer 52

Uronilinogen

Question 53

Enzymes in heme synthesis inhibited by lead

Answer 53

ALA dehyratase | Ferrochelatase

Question 54

Most common form of porphyria

Answer 54

Porphyria cutanea tarda

Question 55

Porphyria that occurs before the formation of ring leads to accumulation of ALA and PBG and lead to what symptom

Answer 55

Neuropsychiatric

Question 56

Accumulation of porphyrinogens in the skin can undergo spontaneous oxidation to porphyrins and cause this symptom

Answer 56

Photosensitivity

Question 57

Direct or Indirect hyperbilirubinemia? Dubin- Johnson Rotor

Answer 57

Direct

Question 58

Crigler Najjar and Gilbert syndrome can cause what type of hyperbiliruninemia

Answer 58

Indirect

Question 59

Epinephrine, cortisol and GH has similar effects to what hormone

Answer 59

Glucagon

Question 60

Principal site of metabolism of branched chain amino acids

Answer 60

Skeletal muscle

Question 61

Energy store used for sprinting

Answer 61

Creatine phosphate

Question 62

Energy store used in marathons

Answer 62

Glycogen and fatty acids

Question 63

In fasting state, glycogen is used as fuel for how many hours into the fasting?

Answer 63

18-24 hours

Question 64

Peak of Ketone bodies being used as fuel in starvation

Answer 64

10 days