Question

Averaged over a few heartbeats, venous return is

Answer 1

Answer:

A. Equal to cardiac output

Explanation:

Venous return refers to the rate at which blood flows back to the heart.

Averaged over a few heartbeats and over steady state conditions, venous return is equal to cardiac output. This is because the cardiovascular system is a closed loop made up of the pulmonary and systemic circulations.

The reason why the venous return must equal cardiac output is to avoid the accumulation of blood in one of the two circulations in the cardiovascular system.

Some of the mechanisms for venous return include;

1.) Exercise

2.) Gravity

3.) Thoracic pump and

4.) Pressure Gradient

5.) Skeletal muscle pump