Purines, Pyrmidines, DNA/RNA structure

Question 1

Inherited changes result from…

Answer 1

Changes in the linear DNA sequence (mutations)

Question 2

3 components of a nucleotide

Answer 2

surgar + phosphate + base

Question 3

DNA runs in what direction?

Answer 3

5’ —-> 3’

Question 4

What results from the action of topoisomerase-1?

Answer 4

1 strand break, 1 catalytic cycle, relaxes 1 coil

Question 5

What results from the action of topoisomerase-2?

Answer 5

2 strand breaks, 2 supercoils, untangles DNA, 1 cycle

Question 6

T/F topoisomerase-2 is temperature sensitive?

Answer 6

True

Question 7

Why are topoisomerases common drug targets?

Answer 7

because they are important in replication because supercoils prevent replication (anti-microbials and anti-cancer, e.g ciprofloxin, topotecan)

Question 8

What weak intermolecular force(s) contribute to the stability of DNA?

Answer 8

stacking forces of the bases

Question 9

What is the overall charge on the outer surface of DNA?

Answer 9

Negative

Question 10

Alkali environments have what effect on DNA and RNA?

Answer 10

Separates DNA and RNA but does not cleave DNA in to monomers as it does RNA

Question 11

What is TM

Answer 11

50% DNA separation

Question 12

rRNA

Answer 12

forms ribosomes

Question 13

tRNA

Answer 13

carries amino acids to ribosomes to be incorporated in proteins

Question 14

mRNA

Answer 14

messenger RNA to carry info from nucleus to the ribosomes