Section 1: Chapter 2: Nucleic Acids

Question 1

What is the structure of a RNA molecule?

Answer 1

• Ribose pentose sugar.
• Phosphate group.
• bases AUCG.

Question 2

What bond forms between nucleotides ( between sugar and phosphate)?

Answer 2

Phosphodiester bond.

Question 3

What is the function of RNA?

Answer 3

• Transfer DNA from DNA to ribosomes.

- Protein synthesis.

Question 4

Who discovered the structure of DNA?

Answer 4

Watson and Crick.

Question 5

What is the structure of DNA?

Answer 5

• Deoxyribose pentose sugar.
• bases ATCG.
• Double stranded.

Question 6

What bond holds together the two strands of DNA?

Answer 6

Hydrogen bonds.

Question 7

What makes DNA stable?

Answer 7

• Phosphodiester backbone protects reactive bases.

- 3 hydrogen bonds between C-G, so the more C-G pairings, the more stable the molecule.

Question 8

What is the function of DNA?

Answer 8

Holding hereditary material and passing genetic info to cells.

Question 9

How is DNA adapted for it’s function? (3 points)

Answer 9

• Stable so rarely ever mutations.
• H bonds weak so strands can be repeated in DNA replication and protein synthesis.
• Large - large amount of info.

Question 10

What does semi-conservative replication mean?

Answer 10

One DNA strand is conserved, one new strand is created.

Question 11

Describe the process of DNA replication.

Answer 11

1) DNA helicase breaks the H bonds between strands.
2) free nucleotides bind the comp bases on the template strand.
3) DNA polymerase makes phosphodiester bonds between newly attached nucleotides.

Question 12

What does ATP stand for?

Answer 12

Adenosine triphosphate.

Question 13

What is the structure of ATP?

Answer 13

• Adenine.
• Ribose pentose sugar.
• 3 phosphates.

Question 14

How does ATP release energy?

Answer 14

Bonds between phosphate groups very unstable, so break easily, to release energy.

Question 15

What is the role of ATP?

Answer 15

Immediate energy source.

Question 16

What 4 processes is ATP used in?

Answer 16

• Metabolic processes.
• Movement - muscle contraption.
• Active transport - changes shape of carrier proteins.
• Secretion - forms lysosomes.

Question 17

What are the 5 key properties of water?

Answer 17

1) Metabolite.
2) Solvent.
3) High latent capacity.
4) Large latent heat of vaporisation.
5) Strong cohesion.

Question 18

What is mean’t by saying water is a good solvent?

Answer 18

Many substances can dissolve in it.

Question 19

What is mean’t by saying water has a high specific heat capacity?

Answer 19

Lots of energy is required to raise the temperature of water.
Because heat energy used to break H bonds.
Good as organisms internal temps stay constant.

Question 20

Can polar molecules dissolve in water?

Answer 20

Yes.

Question 21

Can non-polar molecules dissolve in water?

Answer 21

No.

Question 22

What is mean’t by saying water has a large latent heat of vaporisation?

Answer 22

Lots of energy is required to turn water from liquid to gas.

Good for cooling. When we sweat, lots of heat energy is transferred from our skin to the sweat to evaporate it.

Question 23

Where are inorganic ions found?

Answer 23

Cytoplasm.

Question 24

What are some example of inorganic ions?

Answer 24

• Hydrogen - in enzymes.
• Iron - in haemoglobin.
• Sodium - in co-transport.
• Phosphate - in DNA and ATP.