{Excretion} Abdul-Tchoufon

Question 1

What is Excretion?

Answer 1

(i love you 3000) The removal of metabolic wastes from the body.

Question 2

What does the term metabolism?

Answer 2

It is the total of all chemical reactions that take place in a body cell.

Question 3

What waste products form during metabolism?

Answer 3

CO2, excess water, salts and nitrogenous wastes (e.g. urea, uric acid and creatinine.)

Question 4

What happens when waste products are not continuously removed in body cells and are left to accumulate?

Answer 4

The waste products will poison the cells and inhibit normal functioning.

Question 5

Explain how excretion in humans occur?

Answer 5

• The metabolic waste products diffuse out the cells via the tissue fluid that surrounds them, to the blood in the vessels.
• The waste products are transported in the blood to other excretory organs. These organs have the ability to remove these waste products from the bloodstream and release them out of the body.

Question 6

Name the different excretory organs?

Answer 6

Lungs, Kidneys and Bladder, Liver and intestines and skin.

Question 7

What do the lungs excrete?

Answer 7

CO2, water vapour and heat.

Question 8

What do the Kidneys and Bladder excrete?

Answer 8

urine which consists of :

• excess water
• mineral water
• nitrogenous waste products, namely urea, uric acid and creatinine.

Question 9

What do the Liver and Intestines excrete?

Answer 9

• Urea and Bile pigments
• Urea is transported in the blood to the kidneys and is excreted in urine
• Bile pigments pass into the small intestine and are excreted as bile salts in faeces

Question 10

What does the skin excrete?

Answer 10

sweat via the sweat glands which consists of:
*excess water
*salts
*