Molecular Biology (1)

Question 1

What are the three components of a nucleotide?

Answer 1

Cyclic nitrogenous base
Pentose sugar
One to three phosphates

Question 2

Are the bases in nucleotides acidic, neutral, or basic?

Answer 2

Weakly basic

Question 3

How many rings do purines have?

Answer 3

Two

Question 4

Which bases are purines?

Answer 4

Guanine

Adenine

Question 5

How many rings do pyrimidines have?

Answer 5

One

Question 6

Which bases are pyrimidines?

Answer 6

Uracil
Thymine
Cytosine

Question 7

Which type of pentose sugar has -OH at the 2’ position?

Answer 7

Ribose

Question 8

Which type of pentose sugar has -H at the 2’ position?

Answer 8

2-deoxyribose

Question 9

What are the two components of a nucleoside?

Answer 9

Pentose sugar

Nitrogenous base

Question 10

What are the four ribonucleosides?

Answer 10

Adenosine
Guanosine
Cytidine
Uridine

Question 11

What are the four deoxyribonucleosides?

Answer 11

Deoxyadenosine
Deoxyguanosine
Deoxycytidine
Deoxythymidine

Question 12

At which position on the pentose sugar is the nitrogenous base?

Answer 12

1’

Question 13

At which position on the pentose sugar are the phosphates?

Answer 13

5’

Question 14

What type of bond joins adjacent nucleotides in a polynucleotide chain?

Answer 14

3’-5’ phosphodiester linkage

Question 15

What is the most common form of DNA and what is it characterised by?

Answer 15

B form

Alternating major groove and minor groove between antiparallel strands

Question 16

Which type of enzyme cleaves phosphodiester bonds?

Answer 16

Nucleases

Question 17

Which type of enzyme catalyses phosphodiester bond formation in dsDNA?

Answer 17

DNA ligase