SA:V

Question 1

What is SA:V?

Answer 1

Surface area to volume ratio.

Question 2

What is Fick’s law?

Answer 2

How fast diffusion works is proportionate to the surface area.

Rate of diffusion = SA x Conc. difference/
Thickness of membrane

Question 3

What factors affect the rate of diffusion?

Answer 3

• Temperature (The particles move around faster when the temperature is high, so they diffuse faster).
• Metabolic rate (If chemical reactions are faster, products and reactants are used up faster).

Question 4

How do you work out SA:V?

Answer 4

Example-
- A cubes size is 4x4x4
- A cube has 6 sides
- To clculate surface area (4x4x6=96)
- To calculate volume (4x4x4=64)
- SA:V = 3:2 (simplified)

• SA = height x width x no.sides
• V = height x width x length

Question 5

What does a larger SA:V indicate?

Answer 5

Faster diffusion.