Nucleic Acids

Question 1

What are the 2 best known nucleic acids?

Answer 1

Ribonucleic acid and deoxyribonucleic acid

Question 2

What is DNA?

Answer 2

The material that passed on features of organisms from one generation to the next

Question 3

What does DNA carry?

Answer 3

Genetic information

Question 4

What are the two most important structural features of DNA?

Answer 4

• Double helix structure
• made up of nucleotides that have 3 basic components

Question 5

What 3 things make up a nucleotide?

Answer 5

1) a Pentose sugar
2) a phosphate group
3) a nitrogen containing organic base (A, U, C, G, T)

Question 6

By what kind of reaction is a mono-nucleotide formed?

Answer 6

A condensation reaction.

Question 7

How do two mono nucleotides join to make a di-nucleotide?

Answer 7

Between phosphate group of one and deoxyribose sugar of one. - via condensation reaction

Question 8

What bond holds adjacent nucleotides together?

Answer 8

Phosphodiester

Question 9

What is the structure of RNA?

Answer 9

Single, relatively short polynucleotide chain

Question 10

What sugar has RNA got?

Answer 10

Ribose

Question 11

What are RNA’s organic bases?

Answer 11

-Adenine
-Guanine
-Uracil
-Cytosine

Question 12

What are 3 uses of RNA?

Answer 12

1) transfer genetic information from DNA to ribosomes
2) Make up ribosomes (made of protein and other RNA)
3) Protein synthesis

Question 13

What bonds form between bases on opposite strands?

Answer 13

Hydrogen bonds

Question 14

What are the complimentary base pairs?

Answer 14

• A with T(or U in RNA)
• G with C

Question 15

In DNA, are the quantifies of (A and T) and (G and C) always the same?

Answer 15

Yes

Question 16

What does the deoxyribose and phosphate group wound around one another (forming the double helix) provide?

Answer 16

A structural backbone

Question 17

How do the phosphodiester bonds make DNA a stable molecule?

Answer 17

Protects the more chemically reactive organic bases inside the double helix.

Question 18

How do hydrogen bonds make DNA a stable molecule?

Answer 18

They link the organic base pairs forming bridges between the phosphodiester uprights

Question 19

What holds the molecule together and also makes it more stable?

Answer 19

Interactive forces between the base pairs that hold the molecule together (base stacking)

Question 20

What provides evidence for large genetic diversity?

Answer 20

There are an infinite variety of base sequences as there are 3.2 billion base pairs in the DNA of a typical mammalian cell

Question 21

Why is the adaptation of DNA having a stable structure important? (2)

Answer 21

• Means it can pass through generations
• mutations are repaired so persistent mutations are rare.

Question 22

Why is the adaptation of DNA having hydrogen bonds important?

Answer 22

The two separate strands are joined so replication can occur by separating strands for protein synthesis.

Question 23

Why is the adaptation of DNA being very large important?

Answer 23

Can carry immense amounts of genetic information.

Question 24

Why is the adaptation of DNA having a helical cylinder important?

Answer 24

The base pairs are inside the cylinder so genetic information is protected from being corrupted by outside chemical and physical forces.

Question 25

Why is the adaptation of DNA’s base pairing important?

Answer 25

Leads to DNA being able to replicate and transfer information as mRNA.

Question 26

How is the double helix formed?

Answer 26

The hydrogen bonds joining the strands entwine the strands.

Question 27

Who contributed to the discovery of DNA structure?

Answer 27

James Watson and Francis Crick