Biology Paper 2 Topic 8 – Exchange and Transport in Animals

Question 1

How do you calculate the rate of diffusion using Fick’s Law

Answer 1

Rate of diffusion ∝ surface area x concentration difference / diffusion thickness of membrane.

Question 2

How do you calculate cardiac output

Answer 2

Cardiac output = stroke volume x heart rate

Question 3

What is aerobic respiration

Answer 3

Series of chemical reactions that take place mostly inside mitochondria in the cell. This is an exothermic process because it releases energy. This happens continuously in living cells. It is the main source of energy for cells.

Question 4

Use of energy from respiration in animals

Answer 4

For metabolic processes to build larger molecules from smaller ones, e.g. proteins from amino acids, large carbohydrates (e.g. starch, glycogen) from small sugars (e.g. glucose), fats from fatty acids and glycerol.
To enable muscle contraction.
In birds and mammals, also to maintain steady body temperature in colder surroundings.

Question 5

What is cellular respiration

Answer 5

An exothermic reaction which occurs continuously in living cells to release energy for metabolic processes, including aerobic and anaerobic respiration.

Question 6

Uses of energy from respiration in plants

Answer 6

To build larger molecules from smaller ones, e.g. sugars, nitrates and other nutrients into amino acids, which are then used to make proteins.