Understanding Blood Vessels and Circulation

What is the primary function of veins in the circulatory system?

• To carry oxygenated blood away from the heart

• To carry deoxygenated blood back to the heart

• To exchange gases and nutrients with tissues

• To regulate blood pressure

Which of the following best describes the function of arteries?

• To transport waste products to the kidneys

• To carry oxygenated blood away from the heart

• To store blood for emergencies

• To filter blood

What is the main role of capillaries in the circulatory system?

• To transport hormones throughout the body

• To connect veins and arteries

• To facilitate the exchange of oxygen, carbon dioxide, and nutrients with tissues

• To maintain blood pressure

How is blood flow regulated in the body?

• By the contraction and relaxation of the heart

• By the dilation and constriction of blood vessels

• By the amount of blood produced by the liver

• By the oxygen content in the blood

What is the primary role of haemoglobin in oxygen transport?

• To dissolve oxygen in the plasma

• To bind oxygen molecules and transport them to tissues

• To convert oxygen into carbon dioxide

• To store oxygen in the liver

During exercise, what happens to the oxygen demand of muscles?

• It decreases

• It remains the same

• It increases

• It becomes negligible

What is the effect of regular exercise on the resting heart rate?

• It increases the resting heart rate

• It decreases the resting heart rate

• It has no effect on the resting heart rate

• It causes irregular heartbeats

How does the body ensure that more oxygen is delivered to muscles during exercise?

• By decreasing blood flow to the muscles

• By increasing the heart rate and dilating blood vessels

• By reducing the amount of haemoglobin in the blood

• By decreasing the breathing rate

What happens to the capillaries in muscles during exercise?

• They constrict to reduce blood flow

• They dilate to increase blood flow

• They remain unchanged

• They collapse due to increased pressure