Excretion

Question 1

What are the excretion organs?

Answer 1

The kidneys

Question 2

What is the role of the kidneys?

Answer 2

1) Removal of urea
2) Adjustment of ion levels
3) Adjustment of water content

Question 3

What is excretion?

Answer 3

Removal of metabolic waste products

Question 4

What is ultrafiltration?

Answer 4

1) Blood from the renal artery flows through the glomerulus
2) A high pressure is built up which squeezes water, urea, ions and glucose out of the blood and into the Bowman’s capsule
3) The membranes between the blood vessels in the glomerulus and the Bowman’s capsule act like filters, so big molecules like proteins and bloods cells are not squeezed out

Question 5

What is reabsorption?

Answer 5

1) All the glucose is reabsorbed from the proximal convoluted tubule so that it can be used in respiration. The reabsorption of glucose involves active transport
2) Sufficient ions are reabsorbed
3)Sufficient water is reabsorbed from the collecting duct into the bloodstream by osmosis