Surface area:volume

Question 1

Define metabolism

Answer 1

The sum of all the chemical reactions in a cell

Question 2

Describe what is meant by metabolic rate

Answer 2

Metabolic rate is the rate at which chemical reactions happen within the cells of an organism.

Question 3

Describe the relationship between oxygen consumption and metabolic rate

Answer 3

Metabolism requires ATP, and oxygen is required to synthesise ATP, therefore the greater the rate of oxygen consumption, the greater the metabolic rate.

Question 4

Volume of a sphere

Answer 4

4/3 πr^3

Question 5

SA of a sphere

Answer 5

4 πr^2

Question 6

Limiting Factors for Rate of Diffusion

Answer 6

1. Surface area: volume
2. Diffusion distance
3. Concentration gradient
4. Membrane permeability

Question 7

Features of an effective exchange surface

Answer 7

• Large surface area to volume ratio
• Very thin
• Selectively permeable
• Movement of the environmental medium
• Movement of the internal transport medium

Question 8

Explain why movement of the transport medium is important

Answer 8

Movement of the transport medium ensures that a concentration gradient is maintained, preventing equilibrium and therefore maintaining the rate of diffusion.