Respiratory gases -respiration, Biology

Respiratory Gases -Respiration

Physiologically the most important gases are oxygen, carbon dioxide and nitrogen. Molecular oxygen comprises 21% of the atmosphere; carbon dioxide is only 0.3% while nitrogen forms 78.0%. All the gases present in the air exert a combined pressure which is referred to as one atmosphere (760 mm Hg) or 101.3 k Pa. Most of the oxygen is in the air but some of it is also dissolved in the bodies of water and in soil water. An animal's immediate source of oxygen or respiratory medium therefore, is either water or air. Comparison of the gaseous composition and physical characteristics of air and water emphasise the adaptations needed by terrestrial and aquatic animals to overcome the problems of respiration. For example, the oxygen content of air is about 20 times that of water saturated with air. The diffusion rate for oxygen in air is much more than the diffusion rate in water. In addition there is another hazard. Carbon dioxide diffuses rapidly from air into water. Therefore, elimination of carbon dioxide in water and air are different.

 Extraction of oxygen from different media thus presents special problems as a result of the physical characteristics of the environment. Therefore, to understand the physiology of respiration, we must have a basic knowledge of some of the physical properties of gases. The exchange of oxygen and carbon dioxide either in the respiratory organ or at the tissue level is dependent on the partial pressure, concentration and diffusion of gases. Let us consider them one by one.

Posted Date: 1/15/2013 6:20:03 AM | Location : United States







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

Write discussion on Respiratory gases -respiration
Your posts are moderated
Related Questions
Explain the Protection of erythrocytes and cell membrane? Protection of erythrocytes: Vitamin E protects erythrocytes from haemolysis by the production of oxidizing agents

Give one example in each case of (a) a fixed joint, (b) a ball and socket joint, (c) a hinge joint.   (a) The bones of the skull, the junction of pelvic gi

The Physical Environment   The actual hospital environment is another factor that may be stressful for the child and family. There are many unfamiliar sights, sounds and smells

What is a plant-incorporated protectant? Plant-incorporated protectants are pesticidal substances formed and used by the living plant, typically to protect the plant from pests

Cyanide - Enzyme-activity Control Plants generate cyanide from cyanogenic glucides and histidines. Ethylene biosynthesis is also accompanied by cyanide production. Nitrate red

AMPHE T AMINE S - Commonly called pep pills or antisleep drugs. They increase physical & mental performance. Taken by truck drivers, student & night workers to keep

Define two basic principles of food processing? The fundamentals of food processing, as you may recall, involves the following two basic principles: Prepare the products


Write about embryonic stem cell invitro methord in which transgenic animal were generated and efficient show how homologous recombination happening?

The ability to maintain myocardial perfusion at constant levels in the face of changing driving presence is termed autoregulation. In normal cases, autoregulation is maintained at