人體循環：練習題

In the human heart, which chamber is responsible for pumping oxygenated blood at high pressure through the aorta to the rest of the body?

In the human heart, blood is pumped to the lungs through a specific vessel. If the semi-lunar valve of this vessel fails to close properly during ventricular diastole, what would be the immediate consequence for the circulatory system?

In the human circulatory system, blood travels through different types of vessels. A scientist measures the structural properties of a vessel and finds it has thin walls and valves.

Which statement correctly identifies this vessel and the reason for its structural features?

During vigorous exercise, the human body must adjust to meet the increased energy demand of muscle tissues.
Which sequence of physiological changes correctly describes how the circulatory and respiratory systems respond to this demand?

Which of the following statements correctly explains how the structure of a red blood cell is related to its function in the circulatory system?

Explain how the thickness of the left ventricle wall is related to its specific function in the human double circulatory system.

Compare the structural adaptations of arteries and veins in the human circulatory system, explaining how these structures relate to the pressure of the blood they carry and the prevention of back-flow.

A patient has a resting heart rate that is highly irregular. Name the specific group of cells in the heart that typically controls the natural resting heart rate and suggest a medical device that could be used to treat this condition.

A double circulatory system is essential for maintaining high metabolic rates in humans.

a) Explain why the wall of the left ventricle is significantly thicker than the wall of the right ventricle.
b) Red blood cells are highly specialised for their role in circulation. Describe two structural features of a red blood cell and explain how each feature aids in the transport of oxygen.
c) Coronary heart disease occurs when fatty material builds up in the coronary arteries. Explain how this build-up can lead to a heart attack.

A patient is diagnosed with an irregular heartbeat and is fitted with an artificial pacemaker.

a) Name the specific group of cells that usually controls the natural resting heart rate and state their exact location in the heart.
b) The heart is described as a 'double circulatory system'. Explain what this means in terms of the pathway of blood flow.
c) Describe how the structure of an artery is adapted to withstand the high pressure of blood being pumped from the ventricles.