L8 biochem

Question 1

methyl group from epinephrine is from

Answer 1

S adenosyl methionine

Question 2

VMA is indicator of disease

Answer 2

pheochromocytoma (mainly epinephrine)
neuroblastoma (mainly norepinephrine)

Question 3

enzyme for catecholamine synthesis

Answer 3

tyrosine hydroxylase

Question 4

enzyme for melanin synthesis

Answer 4

tyrosinase

Question 5

tyrosine hydroxylase is

Answer 5

iron containing enzyme

Question 6

tyrosinase is

Answer 6

copper containing enzyme

Question 7

what are the clinical application of catecholamine

Answer 7

-parkinson disorder
-pheochromocytoma

Question 8

describe parkinson disease

Answer 8

it is neurodegenerative movement disorder due to insufficient dopamine production.
since dopamine cant cross BBB so we use its precursor which is DOPA can cross BBB that is how parkinson can be treated

Question 9

describe pheochromocytoma

Answer 9

it is excessive production of catecholamine and hypertension. this cause increase catabolic end product of catecholamine increased (vanillylmandelic acid)
this treated by alpha methyl tyrosine which compete with tyrosine for tyrosine hydroxylase enzyme

Question 10

what are the fate of VMA

Answer 10

-excreted in the urine
-conjugated with sulphate or glucuronic acid

Question 11

tyrosinemia type 1 is due to

Answer 11

deficiency of fumarylacetoacetate hydrolase

Question 12

tyrosinemia type 2 is due to

Answer 12

deficiency of tyrosine aminotransferase

Question 13

tyrosinemia type 3 is due to

Answer 13

deficiency of 4 hydroxyphenylpyruvate dioxygenase

Question 14

alkaptonuria is due to

Answer 14

deficiency of homogentisate oxidase

Question 15

what are the symptoms of alkaptonuria

Answer 15

-homogentisic aciduria
-large joint arthritis
- black pigmentation of cartilage and collagenous tissue

Question 16

how can we diagnose alkaptonuria

Answer 16

-positive benedict test due to reducing substance in urine
-dark staining of the diapers

Question 17

what are the treatment of alkaptonuria and tyrosinemia ?

Answer 17

restriction protein diet especially protein which contain phenylalanine and tyrosine (to help reduce the level of homogentisic acid)

Question 18

what are the symptoms of acute tyrosinemia ?

Answer 18

vomiting
diarrhea
liver failure

Question 19

what are the clinical picture of chronic tyrosinemia

Answer 19

mental retardation
liver cirrhosis