Transport in animals: Practice Questions

Which of the following describes the correct direction of blood flow in the main blood vessels of the human circulatory system?

A student is examining a blood vessel in a diagram. It has a very thin wall (only one cell thick) and a very narrow lumen.

What is the function of this type of blood vessel?

A student records the relative blood pressure and the oxygen concentration in four different blood vessels, labeled W, X, Y, and Z, in a healthy human. The findings are summarized below:

Which vessel is the pulmonary artery?

Which blood component is primarily responsible for the clotting of blood to prevent blood loss and the entry of pathogens?

Mammals have a double circulatory system, as shown in the diagram. What is the main advantage of a double circulation compared to the single circulation found in fish?

State the names of the four main components that make up human blood.

Explain how the thickness of the wall and the size of the lumen in an artery are adapted to transport blood under high pressure from the heart.

The diagram shows a cross-section of a human heart.

Explain why muscular wall A is significantly thicker than muscular wall B, and describe how valves C and D respond to pressure changes during ventricular contraction to ensure blood is forced into the aorta.

The diagram shows a vertical section through a human heart and its associated blood vessels.

(a) Identify the blood vessels labeled A and B.

(b) The muscular wall of the left ventricle is significantly thicker than the muscular wall of the right ventricle. Explain the physiological importance of this difference in thickness.

(c) Describe how the action of the heart valves ensures that blood only flows in one direction when the ventricles contract.

(d) A patient is diagnosed with a narrowing of the coronary arteries. Suggest why this condition can lead to the heart muscle failing to contract effectively.