Heart rate and Cardiac Output MCQ - Practice Questions with Answers

Heart rate and Cardiac Output
Heart rate refers to the number of times heart of a person beats. 
Human heart beats about 72 times per minute in an adult person at rest
The heart rate tends to increase during exercise, fever, fear, anger etc.
Heart rate of smaller animals is higher than that of larger animals. It is mainly because smaller animals have high metabolic rate

Tip- 
A pulse refers to rhythmic contraction and relaxation of the aorta and its main arteries. 
The pulse rate is same as heart rate because an artery pulses every time the heart beats

Cardiac output:

The volume of blood ejected from the left or right ventricle into the aorta (pulmonary trunk) per minute is called cardiac output
Heart of a normal person beats 72 times per minute and pumps out 70 ml of blood per beat
It is calculated by the formula
                Cardiac output = stroke volume . heart rate
                                        = 70 ml. 72 per min
                                         = 5040 ml per min
The stroke volume depends on venous return i.e. the amount of blood delivered to the heart by veins
Cardiac output is not constant, it varies with physical activity
During vigorous exercise, cardiac output increases as much as 21L per min