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

Vascular cambium, Vascular Cambium The vascular cambium usually, if no...

Vascular Cambium The vascular cambium usually, if not always, has a dual origin within the primary tissues; from provascular strands, and from the "ground" meristem tissues be

How does the excretory system of nematodes work, How does the excretory sys...

How does the excretory system of nematodes work? The metabolic residuals of nematodes are collected by two longitudinal lateral excretory channels that open in one excretory po

Clinical evaluation of infants and young children, Clinical Evaluation of I...

Clinical Evaluation of Infants and Young Children Approaches to clinical practice advanced in recent year are mostly directed at older children and adolescents. There has not b

How to calculate the requirements for the calcium in body, How to Calculate...

How to Calculate the Requirements for the Calcium in Body? Requirements for calcium depend upon the rate at which calcium is incorporated into bone; they are therefore highest

Show subkingdoms into which the plant kingdom is divided, Q. What are the s...

Q. What are the subkingdoms into which the plant kingdom is divided? The kingdom Plantae is divided into two big subkingdoms: the tracheophytes and the bryophytes (gymnosperms,

The hydrogen ion concentration of stomach, What is the hydrogen ion concent...

What is the hydrogen ion concentration of stomach acid pH=1.6?

Anther, Anther  is the top of a stamen's filament; divided into pollen sacs...

Anther  is the top of a stamen's filament; divided into pollen sacs in which the pollen grains are form.

What is the emperical evaluation, What is the Emperical evaluation Emp...

What is the Emperical evaluation Emperical evaluation based on: i) Time elapsed since stage one surgery - Considering the sigma cycle of bone formation in humans, a time pe

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