2.6 Structure of DNA and RNA

Question 1

What are the 3 components of a nucleotide?

Answer 1

5 carbon pentose sugar
Phosphate group
Nitrogenous base

Question 2

Which carbons are bound in a nucleotide?

Answer 2

Nitrogenous base attaches to the 1’

Phosphate base attaches to the 5’

Question 3

What does DNA stands for?

Answer 3

Deoxyribonucleic acid

Question 4

What does RNA stand for?

Answer 4

Ribonucleic acid

Question 5

What is the difference in the pentose sugar in RNA and DNA?

Answer 5

RNA has ribose

DNA has deoxyribose

Question 6

What are the bases in RNA?

Answer 6

A, C, G and U

Adenine, Cytosine, Guanine and Uracil

Question 7

What are the bases in DNA?

Answer 7

A, C, G and T

Adenine, Cytosine, Guanine and Thymine

Question 8

How do different nucleotides bond?

Answer 8

• Phosphate grp of one nucleotide attaches the the sugar of another (3’ - OH)

Question 9

What kind of bond holds nucleotides together?

Answer 9

Phosphodiester

Question 10

What is the by-product of Nucleic acids bonding?

Answer 10

Water

Question 11

How do adenine and thymine bond?

Answer 11

2 hydrogen bonds

Question 12

How do guanine and cytosine bond?

Answer 12

3 hydrogen bonds

Question 13

Why do we say DNA is antiparrallel?

Answer 13

Because the two strands run in opposite directions to one another

Question 14

What is the arrangement of DNA?

Answer 14

A double helix with about 10-15 bases per twist

Question 15

Who proposed the current DNA structure?

Answer 15

James Watson and Francis Crick

1953

Question 16

Which bases are purines?

Answer 16

Adenine and Guanine

Question 17

Which bases are pyrimidines?

Answer 17

Cytosine and Thymine

Question 18

Who organised DNA into a helical structure?

Answer 18

Rosalind Franklin

Question 19

How did R. Franklin confirm the DNA arrangement?

Answer 19

Using x-ray crystallography