Nucleic Acid

Question 1

What is the structure of a nucleotide?

Answer 1

Pentose sugar
Nitrogenous base
Phosphate group

Question 2

What is the structure of a nucleoside?

Answer 2

Pentose sugar

Nitrogenous base

Question 3

What is a nucleic acid?

Answer 3

Two or more nucleotides joined together

Question 4

What is a pentose sugar?

Answer 4

A furanose ring

Question 5

What type of nitrogenous base has a single ringed structure and give examples?

Answer 5

Pyrimidine

• Thymine
• Cytosine
• Uracil

Question 6

What type of nitrogenous base has a double ringed structure and give examples?

Answer 6

Purine

• Adenine
• Guanine

Question 7

What molecule is bonded to the 2’ position in DNA?

Answer 7

Hydrogen

Question 8

What molecule is bonded to the 2’ position in RNA?

Answer 8

Hydroxyl

Question 9

What are the differences between DNA and RNA?

Answer 9

DNA = double stranded, thymine paired to adenine 
DNA = single stranded, uracil paired to adenine

Question 10

How many phosphate groups are there in a nucleoside mono-, di- and tri- phosphate?

Answer 10

1, 2, 3

Question 11

What are the functions of nucleic acids?

Answer 11

Energy currency 
Signalling
Cofactors and coenzymes 
Metabolic intermediates 
Transmission of genetic information

Question 12

What components are found in ATP?

Answer 12

Adenine base
Pentose sugar
Three phosphate groups

Question 13

What type of bond forms between adenine and the pentose sugar in ATP?

Answer 13

Ester

Question 14

What type of bond forms between the pentose sugar and the first phosphate group in ATP?

Answer 14

Ester

Question 15

What type of bond forms between individual phosphate groups in ATP?

Answer 15

Anhydride

Question 16

How is energy obtained from ATP?

Answer 16

By breaking the ATP molecule into separate components

Question 17

What molecules are produced after phosphoryl transfer?

Answer 17

ADP + Pi

Question 18

What molecules are produced after pyrophosphoryl transfer?

Answer 18

AMP + Pi + Pi

Question 19

What molecules are produced after adenylyl transfer?

Answer 19

AMP + PPi

Question 20

What transfer results in the production of ADP + Pi from ATP?

Answer 20

Phosphoryl

Question 21

What transfer results in the production of AMP + Pi + Pi from ATP?

Answer 21

Pyrophosphoryl

Question 22

What transfer results in the production of AMP + PPi from ATP?

Answer 22

Adenylyl

Question 23

What is a cofactor?

Answer 23

A molecule that helps or facilitates certain enzymatic reactions

Question 24

What is a coenzyme?

Answer 24

An organic carrier molecule

Question 25

What are the sources of cofactors and coenzymes?

Answer 25

``` Vitamins = organic Minerals = inorganic ```

Question 26

What are the three important cofactors comprised of nucleic acids?

Answer 26

NADP NAD FAD

Question 27

What is autocrine signalling?

Answer 27

A single cell produces a molecule which is excreted and then binds to the same cell in order to initiate a response within the cell = self regulating

Question 28

What is paracrine signalling?

Answer 28

A single cell produces a molecule with is excreted and then binds to another cell within the same tissue in order to initiate a response = local cell to cell communication

Question 29

What is endocrine signalling?

Answer 29

A single cell produces a molecule with is excreted into the circulatory system and then binds to a cell in another tissue in order to initiate a response = cell to cell communication across tissues

Question 30

What is an example of a nucleic acid involved in cell signalling?

Answer 30

Adenylyl cyclase = converts ATP to cyclic AMP as a result of a signalling molecule binding to receptors on the outside of the cell

Question 31

Name two ways in which nucleic acids act as metabolic intermediates.

Answer 31

- They facilitate the metabolism of certain compounds | - They buffer the build up of toxic compounds

Question 32

What pairing between bases occurs in DNA?

Answer 32

A - T = 2 hydrogen bonds | C - G = 3 hydrogen bonds

Question 33

What pairing between bases occurs in RNA?

Answer 33

A - U = 2 hydrogen bonds | C - G = 3 hydrogen bonds

Question 34

What type of bonds link nucleic acids together in DNA and RNA?

Answer 34

Phosphodiester