Circulatory System

What is the main function of the circulatory system?

• To control and coordinate all the functions of the body
• To circulate nutrients, gases and waste around the body
• To circulate nutrients in the digestive system
• To move gases into and out of the lungs

Blood that leaves the LEFT side of the heart is pumped to:

• the body
• the lungs
• the right side of the heart
• none of the above

What happens to blood at the lungs?

• Oxygen and carbon dioxide enter the blood
• Oxygen enters the blood and carbon dioxide leaves the blood
• Carbon dioxide enters the blood and oxygen leaves the blood
• Oxygen and carbon dioxide leave the blood

Which vessels are thick and muscular and carry blood away from the heart?

• arteries
• veins
• capillaries
• all of the above

In which blood vessels do nutrients, gases and waste pass into and out of the blood?

• arteries
• capillaries
• veins
• Both A and B

Which blood vessels have valves to help keep blood flowing back towards the heart?

• arteries
• capillaries
• veins
• All of the above

Blood is mostly made of:

• plasma
• red blood cells
• white blood cells
• platelets

Which type of blood cell is most important to carrying oxygen to body cells?

• red blood cells
• white blood cells
• platelets
• Both A and B

Which type of blood cell is important to fighting pathogens and protecting you from infection and disease?

• red blood cells
• white blood cells
• platelets
• Both A and C

Blood from the inferior and superior vena cava enters the heart into the:

• right atrium
• left atrium
• right ventricle
• left ventricle