biochem p92-101

Question 1

what blocks complex V?

Answer 1

oligomycin

Question 2

rotenone and barbiturate block

Answer 2

complex 1

Question 3

what is another name for complex II?

Answer 3

succinate dehydrogenase

Question 4

antimycin A blocks what complex?

Answer 4

complex III

Question 5

complex 4 is inhibited by

Answer 5

cyanide, CO

Question 6

what are the 2 amino acids that are purely ketogenic amino acids?

Answer 6

lysine, leucine

Question 7

5 cofactors for pyruvate dehydrogenase?

Answer 7

1. pyrophosphate (B1, thiamine TPP)
2. FAD (B2, riboflavin)
3. NAD (B3, niacin)
4. CoA (B5, pantothenic acid)
5. lipoic acid

Question 8

what inhibits lipoic acid?

Answer 8

arsenic

Question 9

clinical symptoms of arsenic poisoning?

Answer 9

vomitting, rice-water stools, garlic breath

Question 10

during fed state is PFK-2 highly active?

Answer 10

yes (goes along with PFK-1, which is the key enzyme in glycolysis)

Question 11

what is the opposite enzyme to PFK-2?

Answer 11

FBPase-2 (fructose bisphosphatase-2)

Question 12

how does FBPase-2 get activated?

Answer 12

phosphorylation by protein kinase A

Question 13

during fasting state is protein kinase A highly active?

Answer 13

yes, protein kinase A phosphorylates FBPase-2 which converts fructose-6-P to Fructose 2,6 BP during the fasting sate

Question 14

Symptomwise, how is vit E def diff from vit B 12 def?

Answer 14

No megaloblastic anemia, no inc serum methylmalonic acid in vit E def

Question 15

2 functions of vit D?

Answer 15

Inc intestinal absorption of Ca2+, inc bone mineralization

Question 16

What vit def is associated with “corkscrew” hair and subperiosteal hemorrhages?

Answer 16

vit C

Question 17

Edema in Kwashiorkor is due to dec plama oncotic pressure, why does this happen?

Answer 17

Due to liver malfunction (fatty change due to dec apolipoprotein synthesis)

Question 18

What are the 3 consequences of inc NADH/NAD+ ratio in liver?

Answer 18

1. inc pyruvate  lactate (lactic acidosis)
2. inc oxaloacetate  malate (prevents gluconeogenesis leading to fasting hypoglycemia)
3. inc dihydroxyacetone phosphate  glycerol 3 phosphate (combines with fatty acids to make triglyceride leading to hepatosteatosis)

Question 19

Which bonds are stronger in DNA?

Answer 19

G-C bonds, inc melting temperature of DNA

Question 20

What is formed first in purine synthesis?

Answer 20

Sugar + PO3

Question 21

What is formed first in pyrimidine synthesis?

Answer 21

base

Question 22

Precursor for purine synthesis?

Answer 22

Inosine Monophosphate (IMP)

Question 23

Precursor for pyrimidine synthesis?

Answer 23

Orotic Acid, UMP

Question 24

Which amino acid used in pyrimidine synthesis?

Answer 24

Aspartate

Question 25

signal sequence where splicing occurs?

Answer 25

GU (donor) A-AG (acceptor) on mRNA

Question 26

splicing is mediated by which proteins and significance to their path?

Answer 26

snRNP's, make up Anti Smith Ab's for SLE Dx