The Human Excretory System

Question 1

How do we gain water in the body?

Answer 1

Drinking, respiration, eating

Question 2

How do we lose water in the body?

Answer 2

Sweating, weeing, breathing

Question 3

What do the kidneys do?

Answer 3

Involved with eliminating waste and osmoregulation control of water potential in the blood.

Question 4

What are the small soluble substances in our blood?

Answer 4

Amino acids, urea, glucose, ions, water, plasma

Question 5

What do small soluble substances do in the blood?

Answer 5

They are filtered out.

Question 6

What are the large substances in the blood?

Answer 6

Erythrocytes (RBC)
Leucocytes (WBC)
Hormones
Thrombocytes (Platelets)
Plasma proteins

Question 7

What do large substances do in the blood?

Answer 7

Stay in the blood

Question 8

What is ultrafiltration?

Answer 8

Filters the blood under high pressure, small soluble substances: glucose, ions and water are forced out the blood, dissolve in the blood. Large molecules such as as RBC, WBC, Platelet stays in the blood

Question 9

What is selective reabsorption?

Answer 9

Useful substances are selectively reabsorbed, all the glucose and ions, toxic urea and excess ions are removed in the urine.

Question 10

Where are nephrons found?

Answer 10

Positioned across the cortex and medulla of the kidney.