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
explain mitosis in detail

Define the Features of Phylum Nematoda? Phylum characteristics of Nematoda which are the world's most abundant multicellular organisms are as follows: 1. Nematodes occur in

Formation and Role of Hypoblast Hypoblast is made as a result of two processes. First, some cells individually leave the blastoderm and move down via poly invagination into t

Research Priorities for Effective Utilization of Agro- Industrial By- Products Biotechnology including recombinant DNA techniques provides for genetic modifications in plants a

Assume that your yard has many tall trees that result in about fifty percent of the yard being shaded and fifty percent of the yard being exposed to full sun. The shaded areas and

Since the visual images are projected in an inverted manner on the retina why don't we see things upside down? As the crystalline lens is a convex spherical lens it forms inver

Benthic Zone - Organisation of the Marine Ecosystem The benthic zone is divisible into sub zones horizontally. These are depicted in a cross section portion of the marine habi

Glutamine synthetase catalyzes the incorporation of ammonia into glutamine and deriving energy from the hydrolysis of ATP. This enzyme is named a synthetase and rather than a synth

Metamorphosis The phenomenon of metamorphosis is described as a process during development which involves a remarkable change in morphology and physiology of the larva, so tha

site of fertilistion in human