Mecahnism Comtolling Heart Beat

Question 1

What is the heartbeat controlled by

Answer 1

By the brain
Medulla oblongata

Question 2

What happens if the BO fails

Answer 2

If it fails to send a impulse to the heart, the muscles of the heart will not contract and the heart will not beat

Question 3

What happens during physical activity

Answer 3

During any physical activity, the heart rate ncreases so a more oxygen can get to the body cells and more carbon dioxide can be removed from the blood.

A high carbon dioxide level in arterial blood causes an increase in the heart rate.

Question 4

The sequence of the process is shown alongside.

Answer 4

C02 concentration is high in blood leaving the heart via systemic circuit.

C02 sensor cells (chemoreceptors) in carotid arteries send impulses to medulla oblongata.

Medulla oblongata sends impulse(message) to the pacemaker of the heart to increase the heart beat.

More blood flows to the lungs, and more C02 is expelled.

C02 levels in arterial blood drop to normal and the heart beat returns to normal.