Human respiration, Biology

Assignment Help:

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


Related Discussions:- Human respiration

What is a terrestrial organism, What is a terrestrial organism? 'Terra'...

What is a terrestrial organism? 'Terra' is the Latin word for earth. Thus, an animal that lives on the surface of the earth is known as terrestrial. This is the similar root wo

Describe the impact and burden of heart diseases, Describe the IMPACT AND B...

Describe the IMPACT AND BURDEN OF HEART DISEASES ? No discussion on the epidemiology of heart diseases will be complete without a look at the tremendous burden put by different

Define the public nutrition, Define the Public Nutrition Public nutriti...

Define the Public Nutrition Public nutrition is concerned with improving nutrition in populations in both poor and industrialized countries, linking with continuity and public

Theory of epigenesis - pre-mendelian theory, Theor y of Epigenesis (i)...

Theor y of Epigenesis (i)          It was proposed by C.F. Wolff & supported by Von Baer. (ii)         Wolff proposed that germ cells contain definite but undifferentiated

Atmosphere, Atmosphere is a multilayer blanket of various gases such as N2 ...

Atmosphere is a multilayer blanket of various gases such as N2 (78.80%), O2 (20.95%), Ar(0.93%), CO2 (0.03%), water vapor and some other gases. This envelope extends from earth's c

What is the importance of biotin, What is the Importance of biotin Biot...

What is the Importance of biotin Biotin is involved in a number of important metabolic reactions, probably as coenzymes. Deficiency symptoms are manifest as degenerative cha

What gases was the earth''s primitive atmosphere constituted, Before the em...

Before the emergence of life of what gases was the earth's primitive atmosphere constituted? The earth's primitive atmosphere was fundamentally formed of methane, hydrogen, amm

Why is the human placenta referred to as haemochorial type, What is the opt...

What is the optimum percentage of forest area recommended by the national forest policy (1988) for the plains and the hills respectively? List any four problems caused because of d

What might explain the pattern, A zoologist is investigating a population o...

A zoologist is investigating a population of squirrels whose coat color is controlled by a single gene whose two alleles (B1 & B2) are codominant. B1B1 individuals are black, B1B2

Explain the term - muscle contraction headache, Explain the term - Muscle C...

Explain the term - Muscle Contraction Headache This is one of the most common headaches. It is also known as tension or nervous headaches. They result from sustained contractio

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd