Questions

Question 1

Why are nucleotides such important molecules

Answer 1

they supply energy in the form of ATP and are involved in inheritance as it codes for RNA and DNA

Question 2

describe the structure of a nucleotide

Answer 2

it is made up of 3 parts:
- a 5-carbon pentose sugar
- a phosphate group
- a nitrogenous base

Question 3

what type of reaction joins the components of a nucleotide

Answer 3

condensation reaction

Question 4

how does deoxyribose differ from ribose

Answer 4

deoxyribose has 1 less oxygen atom than ribose

Question 5

Distinguish between a purine base and a pyrimidine base and give examples of each

Answer 5

Purine has 2 nitrogen-containing rings e.g. Adenine
Pyrimidine has 1 nitrogen-containing rings e.g. Cytosine

Question 6

What type of molecule is ATP

Answer 6

nucleotide

Question 7

describe the structure of ATP

Answer 7

It is made up of:
- an adenine base
- the pentose sugar ribose
- 3 phosphate groups

Question 8

ATP is regarded as the universal energy supply molecule. Why is this and how does its structure relate to its role in cells

Answer 8

ATP has the same structure in all cells, meaning it can be transferred between cells

Question 9

How is energy derived from ATP

Answer 9

the phosphodiester bond of the 3rd phosphate group is broken off by hydrolyses

Question 10

which molecule is formed when energy is released from ATP

Answer 10

ADP

Question 11

what type of reactions is involved in the breakdown od ATP

Answer 11

hydrolysis

Question 12

name the enzyme that catalyses the formation and breakdown of ATP

Answer 12

ATPase

Question 13

What does DNA stand for

Answer 13

Deoxyribonucleic acid

Question 14

2 scientists are given credit for discovering the structure of DNA. What are the names of those 2 scientists

Answer 14

James Watson & Francis Crick

Question 15

What shape did Watson and Crick determine the DNA molecule to be

Answer 15

3D double helix

Question 16

DNA is a polymer, which means that it is made up of many repeating monomers. What are the monomers called

Answer 16

nucleotides

Question 17

The “backbone” of the DNA molecule is made up of 2 components. What are they?

Answer 17

the pentose sugar deoxyribose and the phosphate group

Question 18

There are 4 different bases in DNA. What are the names of these bases

Answer 18

Cytosine, Thymine, Adenine and Guanine

Question 19

how many nitrogenous rings do purine bases have and how many rings do pyrimidine bases have

Answer 19

purine bases have 2 nitrogenous rings
pyrimidine bases have 1 nitrogenous rings

Question 20

What are the 2 purine bases in DNA

Answer 20

Guanine and Adenine

Question 21

What are the 2 pyrimidine bases in DNA

Answer 21

Thymine and Cytosine

Question 22

what are the 2 base pairs in DNA

Answer 22

Adenine and Thymine
Guanine and Cytosine

Question 23

what is the name of the bonds that hold the base pairs together

Answer 23

hydrogen bonds

Question 24

what are the products of the condensation reaction joining 2 nucleotides together

Answer 24

Phosphodiester bonds and 2 water molecules

Question 25

Other than the nature of the DNA and RNA pentose sugar, give 3 ways in which the structure of RNA is different from that of DNA

Answer 25

- DNA has 2 strands whilst RNA has 1 strand - DAn is longer than RNA - DNA contains the base Thymine, whilst RNA contains the base Uracil

Question 26

how does the function of tRNA differ from that of mRNA

Answer 26

mRNA provides a template for gene coding, whilst tRNA carries amino acids to ribosomes

Question 27

what makes a DNA molecule stable

Answer 27

the complementary pairing of bases

Question 28

how does a DNA molecule carry 'information'

Answer 28

having a specific sequence of nitrogenous base pairs

Question 29

Explain how complementary base pairing and hydrogen bonding are responsible for the structure of DNA

Answer 29

hydrogen bonds form between the complementary base pairs, holding the 2 DNA strands together, forming a double helix

Question 30

which type of RNA forms ribosomes in association with proteins

Answer 30

rRNA

Question 31

which type of RNA is formed from a single strand of DNA by transcription

Answer 31

mRNA

Question 32

which type of RNA picks up specific amino acids and carries them to the ribosomes

Answer 32

tRNA

Question 33

when do mutations happen

Answer 33

at any time when the DNA is copied