Elimination of waste

Question 1

CARBON DIOXIDE

Answer 1

• gas = waste produce = cellular metabolism
• dissolves in the body fluids = acid solution
• excrete to maintain pH = needs to be within normal range
• excreted through the lungs during expiration

Question 2

URINE

Answer 2

• formed by kidneys
• consists of water, waste products & protein breakdowns
• Urea = influence of hormones
• kidneys = regulate body salt and water balance
• bladder stores urine until excretion

Question 3

FAECES

Answer 3

• water minerals
• digestive system
• defaecation: the process of passing stool out of the body through the anus
• indigestible food remains in the alimentary canal = cannot be absorbed & large number of microbes