Human respiration, Biology

Human respiration

Human beings are adopted for terrestrial mode of life. They conduct pulmonary respiration. This system consists of external nostrils, nasal cavities, pharynx, larynx, trachea, bronchi, bronchioles and lungs. The functional units of the lungs are the thin walled chambers called alveoli.

MECHANISM OF RESPIRATION: Respiration in man occurs in two stages: inspiration and expiration.

a) INSPIRATION: Air enters the lungs through nostrils, nasal cavities, pharynx, and lastly into lungs. The thoracic cavity is increased by pulling the diaphragm down and pushing the ribs forward. Gaseous exchange occurs in the alveoli of lungs.


b) EXPIRATION: During expiration, upward movement of diaphragm and inward movement of ribs reduces thoracic cavity. So the column in lungs is decreased and the air under pressure rushes out of the lungs. In man diaphragm plays a major role in respiration. While in women the ribs play a major role.


304_Human respiration.png

Posted Date: 8/29/2012 8:54:33 AM | Location : United States







Related Discussions:- Human respiration, Assignment Help, Ask Question on Human respiration, Get Answer, Expert's Help, Human respiration Discussions

Write discussion on Human respiration
Your posts are moderated
Related Questions
Considering hybridization in a given trait like the color of the hair of a mammalian species (white/black) conditioned by a pair of different alleles under complete dominance (blac

How does the placement of veins help to carry out their function of transporting materials to and from the leaf ?

Q. After menses what is the hormone that influences the maturation of the ovarian follicles? The maturation of the ovarian follicles after menses is stimulated by the action of

Where does most of the water resorbed after glomerular filtration go? What are the other substances resorbed by the nephron tubules? Only 0.5 to 1% of the glomerular filtrate i

Economic Development and Health The contribution of good health to improved growth and development prospects (or its opposite i.e. the contribution of poor health to reduced e

Open Head Injuries Open head injuries are TBIs in which the skull is penetrated, as in gun shot or missile wounds, or in which fragment of bone penetrate the brain substance. O

Describe what is Circulatory Support and Inotropes ? Colloid or Crystalloids: Hypotension after PGEl infusion is common. It is the result of relative intravascular volume deple

There are several kinds of pollution, main among them are as follows:

a) How do copper and hormone releasing IUDs act as contraceptives? Describe. b) If you squeeze a seed of orange you may be observe many embryos of different sizes.  How is it

What are the Properties of titanium Titanium has several favourable properties like low specific gravity with a density of 4.5 gm/cm 3 , high heat resistance and high strength