2018 and 2019

Question 1

Give two features of DNA and explain how each one is important in the
semi-conservative replication of DNA.

Answer 1

• Weak hydrogen bonds between the bases allow the two strands to separate.
• Two strands act as a template.

Question 2

What is the proteome of a cell?

Answer 2

The proteome is the full range of different proteins that a cell can produce at a given time.

Question 3

Give two structural differences between a molecule of messenger RNA (mRNA) and
a molecule of transfer RNA (tRNA).

Answer 3

mRNA doesn’t have hydrogen bonds whereas tRNA does.
mRNA has codons. tRNA has anticodons.

Question 4

Other than those given, name two variables the student should have controlled.

Answer 4

Temp of the muscle tissue
pH of the ATP solution

Question 5

The nucleus and a chloroplast of a plant cell both contain DNA.
Give three ways in which the DNA in a chloroplast is different from DNA in the
nucleus

Answer 5

DNA is circular not linear
DNA is shorter
Fewer genes

Question 6

Name an organelle found in both a chloroplast and a prokaryotic cell

Answer 6

Ribosome

Question 7

Explain how the active site of an enzyme causes a high rate of reaction

Answer 7

Lowers activation energy. Induced fit causes the active site to change shape. So enzyme substrate causes complex causes bonds to break or develop.

Question 8

Suggest a change the student could make to his procedure so that 10 cm3 of oxygen
would be produced in less than 6 seconds.

Answer 8

Increase temp