Question

Cardiac output is the amount of blood ______.

-in the circulatory system in total.
-pumped by each ventricle per minute.
-pumped per beat of the heart.
-pumped by both the atria and the ventricles per minute

Answer 1

Cardiac output is the volume of blood each ventricle pumps per minute, calculated by multiplying stroke volume by heart rate.

Step-by-step explanation:

Cardiac output is the volume of blood pumped by each ventricle per minute. It is a crucial measure of heart function and can be calculated by multiplying the stroke volume (SV) — the amount of blood pumped by a ventricle in a single beat — by the heart rate (HR) — the number of heart contractions per minute.

The formula for this calculation is CO = HR × SV. Factors that can influence cardiac output include sympathetic stimulation, catecholamines like epinephrine and norepinephrine, thyroid hormones, and levels of certain ions like calcium. Conversely, parasympathetic stimulation and variations in ion levels can decrease cardiac output. It's important to note that cardiac output only refers to the blood flow from the ventricles, not the atria.