Question

In what way was William Harvey’s model of blood flow based partly on a quantitative argument?

Select one:

Harvey counted up all the lung capillary beds and concluded that their total volume could accommodate all the blood pumped from the right ventricle.

Harvey correlated breathing rate with heart rate in exercising subjects, and concluded that the two parameters could only be related if blood circulated.

Harvey calculated that the heart pumped too much blood for it all to be consumed in the tissues.

Harvey observed that the larger the animal, the lower the heart rate.

Harvey measured blood pressure and concluded that the heart pumped forcefully enough to propel blood around the entire system.

Answer 1

Ans.

• People used to belief in the existance of two seperate systems of blood in the body before Harvey's work.
• According to this theory, one system pass the purple nutritive blood with nutrients being circulated through the veins.
• The other system carried out the circulation of vital blood from the lungs with the help of arteries.
• However, Harvey opposes this two system theory by his experimental observations.
• Most of his experiments were focused towards blood flow mechanism in the human body.
• Through the observation of heart's notion in living animals, he pointed out that the active phase in movement of heart was systole, and through muscle contraction it pumped out the blood.
• He percieved that, at any given time the amount of blood recieved from the heart was much greater than the tissues can absorbed.
• Harvey showed that blood can flow only in the direction of heart through the valves of veins and that blood return back to the heart after circulating around the whole body.
• So, with the help of model of blood flow based partly on a quantitative argument, Harvey calculated that the heart pumped too much blood for it all to be consumed in the tissues.
• This model proposed by Harvey laid the foundation of his claim of blood circulation through the venous valves.