Human respiration system is defined as the metabolic activity in Which food is oxidized inside the cells to release energy.
The energy comes up by this process we use this to conduct other life processes and to do different types of work in our daily life.
The human respiratory system consists of the following organs.
About the structure of the nose, you have already studied in the unit Sense Organs.
It has hair and mucous on its inner surface.
The surface is rich in blood vessels also mucous helps in Smelling and it stops dust and other unwanted materials to pass in the nasal cavity.
Hairs also support to stop the passage of unwanted materials inside the nose.
The blood vessels provide suitable temperature to the air which has to the lungs.
The trachea is the windpipe connecting the nose with the bronchi.
It consists of the rings of cartilage.
Pharynx and larynx are also found in contact with it.
The pharynx is the place at which the windpipe and the food pipe tie-up.
At that joint epiglottis is found which conducts the opening and closing of the trachea.
When we swallow food/water, the epiglottis closes the windpipe.
We name larynx as the soundbox which consists of two-fold of vocal cords able to produce sound by its vibration.
We speak by the vibration of the vocal cords.
The trachea carries air to inhale and exhale.
Bronchi are the two branches of the trachea which enter each lung. we call it bronchioles.
Each bronchiole ends in a saclike structure we call it alveolus.
Exchange of O2 and CO2 takes place in the alveoli by the process of diffusion between the inhaled air and the blood cells found in capillaries.
The capillaries surround the alveolus.
There are two lungs in the human respiratory system that lies in the thoracic cage. Each lung is a group of a number (about 30 million) alveoli.
There is two-layer membrane pleura contains a fluid between the layers which protects the walls of the lungs from friction during inhalation and exhalation.
The diaphragm is a muscular layer between the thorax and the abdomen.
The strong muscle conducts the process of inhalation and exhalation process.
When the diaphragm relaxes, the volume of the thorax increases.
It helps to enter the oxygen-rich air in the lungs through the nose and the windpipes. The process is inhalation.
When the diaphragm contracts, the volume in the thorax decreases which increases the pressure inside the lungs.
It pushes the carbon dioxide rich-air to pass out through the earlier path. The process is exhalation.
We jointly call breathing to the process of inhalation and exhalation, that is very necessary for respiration in human beings and other higher animals.
Here you go with full reference of human respiratory system direct in a figure.
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