12- excretion in humans

Question 1

what does excretion mean?

Answer 1

getting rid of waste products from metabolic reaction

Question 2

why is excretion useful

Answer 2

because metabolic reactions release toxic substances, they need to be removed to prevent harm

Question 3

what parts do the kidneys remove

Answer 3

1. excess water
2. excess salt
3. urea

Question 4

how is urea made

Answer 4

1. break down of proteins in the liver to get amino acids
2. amino acids used to make new proteins
3. break down of excess amino acids by deamination