Sec 3 Bio-Excretion

What is excretion?

• Excretion is the removal of undigested food. 

• Excretion is the removal of metabolic waste products.

• Excretion is the maintenance of a constant blood water potential.

• Excretion is the movement of substances.

Which of the following is NOT an example of an excretory waste product?

• carbon dioxide

• oxygen

• urea

• water

The process, _ of excess amino acids, leads to the formation of urea in the liver.

Which of the following is an example of excretion?

• Release of insulin from the pancreas

• Release of saliva from salivary glands

• Removal of carbon dioxide from the lungs

• Removal of faeces from the alimentary canal

The diagram shows the kidney and the three structures X, Y and Z associated with

it.

Where will urea be found?

• X and Z only

• X and Y only

• Y and Z only

• X, Y and Z

What is the process whereby small molecules, such as glucose and urea, pass from the blood into the nephron at the Bowman's capsule?

• Active transport

• Diffusion

• Selective reabsorption

• Ultrafiltration

Which of the following correctly relates the structure to its respective function?

• P:

  Selective reabsorption

• Q:

  Ultrafiltration

• R:

  Ultrafiltration

• S:

  Secretion of ADH

Which substances in the dialysis fluid must be at the same concentration as that in blood?

• Amino acids and urea

• Glucose and amino acids

• Glucose and urea

• Urea and salts