FA 2016 pg 48-51 Biochem

Question 1

Histones are rich in which 2 amino acids

Answer 1

arginine & Lysine

Question 2

what is an Heterochromatin and whats an example

Answer 2

condensed and appears dark on EM
transcriptionally inactive

barr bodies are a type of heterochromatin

Question 3

what s Euchromatin

Answer 3

less condensed & transcriptionally active

Lighter on EM

Question 4

which nucleotide is the template strands undergo methylation

Answer 4

cytosine & adenine

Question 5

methylation represses transcription T or F

Answer 5

T

Question 6

acetylation allows transcription T or F

Answer 6

T

Question 7

what is a nucleoside made up off

Answer 7

Base and sugar (ribose)

Question 8

what is a nucleotide made up off

Answer 8

Base, sugar and phosphate

Question 9

how is the phosphate group linked in a nucleotide and in what direction

Answer 9

using phosphodiesterase bond at 3’-5’ direction

Question 10

what amino acid is necessary for the formation of purine synthesis

Answer 10

Glycine Aspartate & Glutamate

Question 11

what are the starting products of pyrimidine synthesis

Answer 11

glutamate and Co2

Question 12

caramel phosphate to orotic acid is blocked by what drug

Answer 12

leflunomide

Question 13

inhibits dhydroorotate dehydrogenase what drug?

Answer 13

Leflunomide

Question 14

a 3 year old boy is brought to the ER for swollen hands and feet. The boys older brother died at the age of 7 from pneumonia. Physical examination shows a wedge shape infracts in the spleen, what is the MOA for the medication to treat this boy.

Answer 14

Hydroxyurea (inhibit ribonucleotide reductase)

diagnosis sickle cell

Question 15

what three drugs inhibit dihydrofolate reductase

Answer 15

methotrexate, trimethoprim and pyrimethamine

Question 16

what is the antidote to treat the drug that inhibit thymidylate synthase

Answer 16

Uridine used for 5FU toxicity

Question 17

what other drug has the same mechanism of action as Mycophenolate

Answer 17

RIbavirin (block InosineMono Phosphate dehydrogenase)

Question 18

what two drugs inhibit de novo purine synthesis

Answer 18

azathioprine and 6MP

Question 19

what are the findings in Lesch Nyhan syndrome

Answer 19

intellectual disability, self-mutilation, aggression, hyperuricemia, gout, dystonia

Question 20

DNA replication is conservative T or F

Answer 20

F (it is semiconservative involving both continuous and discontinuous synthesis)

Question 21

what specific sequence is found on promoters and origin of replication

Answer 21

AT-Rich sequence

Question 22

deficiency in the protein that unwinds DNA template at replication fork is called?

Answer 22

Bloom syndrome (deficiency of Helicase)

Question 23

what prevents strands from re-annealing

Answer 23

single stranded binding proteins

Question 24

what are the functions of DNA polymerase 3

Answer 24

has a 5’-3’ synthesis & 3’-5’ exonuclease proofreading activity

Question 25

what enzyme degrades RNA primer

Answer 25

DNA polymerase 1

Question 26

what enzyme makes RNA primer

Answer 26

primase

Question 27

what enzyme has a 5'-3' exonuclease activity

Answer 27

DNA polymerase 1

Question 28

A RNA-Dependent DNA polymerase that adds DNA to 3'end of chromosomes to prevent loss of genetic material is called---------

Answer 28

telomerase (eukaryote only)

Question 29

muscle weakness and pain after intense exercise and no ketones

Answer 29

MCAD deficiency (presence of dicarboxylic acid is diagnostic)

Question 30

what enzyme deficiency is associated with sudden infant death syndrome

Answer 30

MCAD

Question 31

doll like faces, protruding tongue hepatomegaly and hyperuricemia refers to what disease?

Answer 31

Von Gierke (def of glucose-6 phosphatase)

Question 32

AR disorder that is due to deficiency of neutral amino acids

Answer 32

Hartnups disease

Question 33

What G.I Pathology is associated with CPG methylation

Answer 33

serrated polyps

Question 34

what are the symptoms of Bloom syndrome

Answer 34

No helicase cause short stature, rash from sun, cafe au lait, leukemia, lymphoma

Question 35

what is the triad of SCID

Answer 35

recurrent infection, diarrhea and failure to thrive

Question 36

what is responsible for joining okazaki fragment together

Answer 36

DNA ligase