Biology Paper 1

Question 1

Describe three features of the alveoli that help maximise gas exchange.

Answer 1

• Increased surface area
• Good blood supply
• One cell thick wall

Question 2

The leaf tissue that contains the most chloroplasts is the

Answer 2

palisade mesophyll

Question 3

Suggest why doctors are concerned about antibiotic resistance.

Answer 3

• Less antibiotics can destroy bacteria
• New antibiotics must be developed taking time and money
• Some diseases cannot be treated

Question 4

How could the oxygen produced during photosynthesis be used to measure the rate of photosynthesis?

Answer 4

Volume of oxygen in a given time

Question 5

Explain the effect of increasing temperature on the rate of photosynthesis.

Answer 5

Increasing temperature at a constant concentration of carbon dioxide increases the rate of photosynthesis.
Increasing temperature increases kinetic energy of particles.

Question 6

Explain the effect of increasing carbon dioxide on the rate of photosynthesis.

Answer 6

Increasing carbon dioxide increases rate of photosynthesis as carbon dioxide is one of the reactants.
Graph plateaus at a certain point due to another factor being limiting.

Question 7

Explain why a cell cannot complete division when affected by a cancer drug.

Answer 7

The fibres cannot line up the chromosomes down the middle of the cell.
Nucleus cannot divide

Question 8

Give a reason why a drug that stops cell division helps to treat cancer

Answer 8

Stops the growth of tumour cells