Which is the main organ of circulation?

• heart

• blood

• capillary

• blood vessels

Which of the following statement about the circulatory system is FALSE?

• The blood in the aorta is oxygenated.

• The blood in the pulmonary vein is oxygenated.

• The blood in the pulmonary artery is oxygenated.

• The blood in the inferior vena cava is oxygenated.

How do arteries differ from veins?

• Arteries carry blood.

• Arteries are thin-walled and are used for gas exchange.

• Arteries have ticker wall layers to accommodate the changes in pressure from the heart.

• Arteries have thinner wall layers and valves and move blood by the action of skeletal muscle.

Which blood vessel carries blood from all parts of the body to the heart?

• aorta

• veins

• artery

• vena cava

Which is NOT a function of the circulatory system?

• It delivers oxygen and nutrients to cells.

• It breaks down carbohydrates into glucose.

• It transports other materials through body.

• It removes carbon dioxide and wastes from cells.

Which statement is TRUE about the human circulatory system?

• It makes the blood cells.

• It transports oxygen and nutrients.

• It breaks down food and releases nutrients.

• It is the first line of defense against bacteria.

How do the respiratory and circulatory system work together?

• They supply the body’s cells with oxygen.

• They are responsible for the movement of the body.

• They break down food into energy and eliminate waste.

• They send chemical signals throughout the body via hormones.

What are the organs of the respiratory system?

• lungs, heart, and blood

• rib cage, diaphragm, and lungs

• nose, lungs, heart, and diaphragm

• lungs, throat, and passageway that lead to the lungs.

What happens in the diaphragm when we exhale (breathe out)?

• The diaphragm relaxes and moves upward.

• The diaphragm contracts and moves upward.

• The diaphragm relaxes and moves downwards.

• The diaphragm contracts and moves downwards.

What important activity takes place in the lungs?

• food is digested

• liquid waste is filtered from the blood

• the trachea is exchanged for the larynx

• oxygen is exchanged for carbon dioxide