Nitrogen Metabolism

Question 1

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

Answer 1

Ammonotelic

Question 2

Seen in birds, which excrete
uric acid as semisolid guano

Answer 2

Uricotelic

Question 3

Seen in land animals,
including humans, who
excrete nontoxic watersoluble
urea

Answer 3

Ureotelic

Question 4

Organ where urea cycle
mainly occurs

Answer 4

Liver

Question 5

This substance functions
solely as an enzyme activator
and regulator of urea
synthesis

Answer 5

N-acetylglutamate

Question 6

Most common enzyme
deficiency of the urea cycle

Answer 6

Ornithine transcarbomylase

Question 7

Purely ketogenic amino acids

Answer 7

Lysine, Leucine

Question 8

Glucogenic and ketogenic
amino acids

Answer 8

Phenylalanine, Tyrosine,
Isoleucine, Tryptophan

Question 9

Deficient enzyme in
phenylketonuria

Answer 9

Phenylalanine hydroxylase

Question 10

Deficient enzyme in alkaptonuria

Answer 10

Homogentisate oxidase

Question 11

Condition resulting from the
darkening of the connective
tissues in patients with
alkaptonuria

Answer 11

Ochronosis

Question 12

Deficient enzyme in albinism

Answer 12

Tyrosinase

Question 13

Most common deficient
enzyme in homocystinuria

Answer 13

Cystathionine β-synthase

Question 14

Amino acids involves in
cystinuria

Answer 14

Cystine, Ornithine, Lysine,
Arginine

Question 15

Deficient enzyme in maple
syrup urine disease

Answer 15

α-ketoacid dehydrogenase
complex

Question 16

Amino acids involved in
maple syrup urine disease

Answer 16

Isoleucine, Valine, Leucine

Question 17

Rate-limiting enzyme of heme
metabolism

Answer 17

δ-Aminolevulinic acid synthase

Question 18

Lead inactivates these
enzymes of heme metabolism

Answer 18

δ-Aminolevulinic acid
dehydratase, Ferrochelatase