Nucleic Acids - Structure and Function 5

Question 1

allows the double helix to reassume 10.5 base pairs per turn by adding or subtracting twist as necessary and replacing them with writhes

Answer 1

superhelicity

Question 2

Superhelicity allows the double helix to reassume 10.5 base pairs per turn by adding or subtracting twist as necessary and replacing them with

Answer 2

writhes

Question 3

sum of twists and writhes

Answer 3

linking number

Question 4

antibiotics that work by interfering with the action of bacterial type II topoisomerases

Answer 4

fluoroquinolones and ciprofloxacin

Question 5

True or false: other topoisomerase inhibitors target prokaryotic topoisomerases and are used in anti-cancer treatments

Answer 5

false; eukaryotic topoisomerases

Question 6

copy a DNA template in the same way that DNA polymerases replicate a parental strand

Answer 6

RNA polymerase

Question 7

directs the synthesis of protein

Answer 7

mRNAs

Question 8

read the information in the mRNA codons and in polypeptide synthesis

Answer 8

tRNA and rRNA

Question 9

play important role in the regulation of gene expression

Answer 9

RNAs

Question 10

True or False: RNA has a role in catalysis

Answer 10

True

Question 11

RNAs that functioned as enzymes

Answer 11

ribozymes

Question 12

suggests that DNA as genetic material and proteins as catalysts arose later, and eventually prevailed because of the advantage they offer

Answer 12

RNA world hypothesis

Question 13

What makes DNA more stable than RNA?

Answer 13

2’ OH in RNA
double strand of DNA

Question 14

True or False: Uracil can also base pair with guanine

Answer 14

True

Question 15

True: RNA was the first genetic material that not only carry information but also catalyze reactions

Answer 15

True

Question 16

The presence of ___________ on ribose makes RNA much more prone to hydrolysis than DNA

Answer 16

2’ hydroxyl

Question 17

least chemically stable base in nucleic acids

Answer 17

cytosine

Question 18

can spontaneously deaminate and in turn is converted to a uracil

Answer 18

cytosine

Question 19

True or False: the presence of thymine indicates the deamination of cytosine

Answer 19

False; presence of uracil

Question 20

True or False: mutations in RNA have much fewer consequences than mutations in DNA

Answer 20

True

Question 21

catalyze important cellular reactions, including the formation of peptide bonds in ribosomes

Answer 21

ribozymes

Question 22

True or False: DNA is not known to be involved in catalysis

Answer 22

True