ZoologyThe heart rate and the stroke volume of a person at rest are 70 beats per minute and 70 mL/beat respectively. During jogging, his heart rate increases to 90 beats per minute and stroke volume increases to 100 mL/beat. During jogging, his cardiac output increased by

The heart rate and the stroke volume of a person at rest are 70 beats per minute and 70 mL/beat respectively. During jogging, his heart rate increases to 90 beats per minute and stroke volume increases to 100 mL/beat. During jogging, his cardiac output increased by

A
5.2 litre/minute
B
4.9 litre/minute
C
3.6 litre/minute
D
4.1 litre/minute

Solution:

Cardiac output = stroke volume x heart rate

His cardiac output at rest = 70 mL/beat x 70 beats/minute = 4,900 mL/minute
His cardiac output during jogging = 90 mL/beat x 100 beats/minute = 9,000 mL/minute
Difference = 9,000 mL/minute - 4,900 mL/minute = 4,100 mL/minute = 4.1 litre/minute