In a classic experiment carried out by the biologist Hop
dic 20 century, 20 young rats were divided into two groups.
One group was fed on a diet of pure carbohydrate, lipid and
protein; the other was fed the same diet. but with some added
milk. The rats were weighed every day. After 18 days the diets
of the two groups were swapped over.
Explain why 20 rats were used rather than just 2

After frida stops exercising, she continues to breathe heavily. what is most likely occurring in her body? heavy breathing during exercise has produced an oxygen surplus in her muscles. this oxygen is being transported to her lungs. this is a result of aerobic respiration. heavy breathing during exercise has produced a carbon dioxide surplus in her muscles. lactate is being transported to her liver. this is a result of aerobic respiration. strenuous exercise has caused her body to be in carbon dioxide debt, and she is breathing hard while lactate is transported to the liver. this is a result of anaerobic respiration. strenuous exercise has caused her body to be in oxygen debt, and she is breathing hard while lactate is transported to the liver. this is a result of anaerobic respiration.