What is the main function of the excretory system?

• to collect and remove wastes from the body
• to strengthen skeletal muscles
• to protect the nervous system
• to bring oxygen to body cells

Under normal conditions, which of the following substances is found in urine?

• blood cells
• protein
• glucose
• urea

In which excretory organ is urea produced?

• skin
• liver
• kidneys
• lungs

Which excretory organ eliminates water and some chemical wastes in perspiration?

• lungs
• skin
• liver
• kidneys

The process of removal of the body’s wastes is called

• gas exchange.
• respiration.
• excretion.
• filtration.

The organ whose excretory functions include detoxification of the blood and formation of urea.

• liver

• kidney

• heart

• gall bladder

The name given to the waste products produced by cellular life processes the most important of which are carbon dioxide, water, urea and mineral salts.

• ATP

• metabolic wastes

• feces

• enzymes

What do the lungs do in the excretory system?

• dispose of carbon dioxide through exhalation

• disposes of smog thru exhalation

• dispose of ultraviolet rays through exhalation

• dispose of rays through exhalation

Which of the following mainly excretes nitrogenous waste, water and salts?

• skin
• kidney
• lungs
• gall bladder

Poisons can build up in the body if organs don't filter and get rid of them. This makes you sick and you could die. What is another name for poisons?

• toxins

• enzymes

• hormones

• insulin