With the help of labelled diagram, discuss the mechanism of respiration in human beings.
Mechanism of respiration- It occurs in following steps:
1. Breathing: Taking in oxygen and expelling carbon dioxide out is called breathing. It involves following steps :
Inhalation: It is taking in oxygen. It occurs due to contraction of muscles attached to ribs and flattened diaphragm which increase the volume of thoracic cavity. Hence, the pressure inside the thoracic cavity decreases and air rushes into of the lungs.
Exhalation: It is expelling of carbon dioxideont. It occurs due to relaxation of muscles attached to ribs and diaphragm is dome shaped. This decreases the volume of thoracic cavity and decreases air pressure and expels CO2 out of the lung.
2 Exchange of gases: It takes place between the alveoli of lungs and surrounding blood capillaries.
3.Transport of gases in blood: Haemoglobin present in the blood transports O2 and CO2 in blood. Oxygen is transported from the lungs to the body cells in the form of any haemoglobin.
4.Oxidation of food: Breakdown of glucose molecules which produce energy. It occurs in mitochondria.