Q. 49 A
What is meant by 'heart beat' ? What is the usual heart beat rate at rest?
One heart beat includes one complete contraction (systole) and relaxation (diastole) of heart. The normal heart beat rate at rest is 72 times /minute.
(b) When a person runs for a while, his heart beat becomes faster because he needs more energy to run.
Rate this question :
What will happen to a plant if its xylem is removed?Evergreen Science
What is meant by blood pressure? How systolic pressure differs from diastolic pressure?Evergreen Science
How is double circulation different from single circulation?All In One Science
Why is diffusion insufficient to meet the oxygen requirements of a multicellular organism like humans?Xam idea - Science