5.1.2 excretion as an example of homeostatic control

Question 1

excretion defintion

Answer 1

removal of metabolic waste from the body

Question 2

importance of removing metabolic wastes?

Answer 2

• eg urea, CO2
• part of homeostasis and maintaining metabolism
• toxic if accumulates in the body. alter pH, and can act as enzyme inhibitors

Question 3

3 main metabolic waste products

Answer 3

co2
bile pigments
urea

Question 4

role of lungs in excretion

Answer 4

• CO2 produced as waste product of respiration
• diffuses from respiring tissues into bloodstream, trnasported MOSTLY AT HCO3- to the lungs
• diffuses into alveoli to be exhaled

Question 5

role of skin in excretion

Answer 5

sweat contains urea, salts, uric acid, water, ammonoia