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
Indifferences in ionic composition Answer A. across membranes can be created through the action of ATP driven pumps as long as number of negative and positive ions on remain equal

Evolution: This deals with the origin of newer types of organism from the previous ones by modification involving genetic changes and adaptations. Evolution also called as biologic


Q. How to Investigate mitral regurgitation by Electrocardiogram? Patients with severe mitral regurgitation often have atrial fibrillation. Left atrial enlargement is a common f

File  & chemical removal of gutta percha: -    K-type file & chloroform is the best choice in small and curved canals. -    The pulp chamber floated with chloroform, then k-typ

Q. How is female gametophyte formed in angiosperms? Into the flower ovary there are megasporangia enclosed by a tegument having a small opening, the micropyle. Inside the megas

Select all that are true or correct regarding a buffer: alternately donating and accepting ions a set of chemicals that work together to resist pH change often a weak acid or base

Determine the Functional Food in Europe? Functional foods are: Conventional/everyday foods consumed as a part of the normal diet; Composed of naturally-occurring co

Define Absorption, Storage and Elimination of vitamins? Reading through this section you would realize that all fat-soluble vitamins undergo similar metabolic fate. They are a

Kidney - 2 in number. Dark red. Slightly flattened. Bean shaped. 10 cm. long, 5 cm wide and 4 cm thick (In rabbit 20-25 mm). Weighing 150 gm in male 135 gm in fema