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
Q. What is the normal duration of the menstrual cycle? How does the calendar contraceptive method work? The normal duration of the menstrual cycle is 28 days but it can vary am

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Explain about the duration of exercise for diabetics patient After selecting an exercise, it is very important to know the vigorous nature, duration and timings of the exercise

What is the chemical nature of carbohydrates? The name carbohydrate owes its origin to the fact that most substances of this class have empirical formulae suggesting that they

STRUCTUR E OF SPERMATOZOAN Structure of sperm is divided into 3 parts -      (1) Head                  (2) Middle piece             (3) Tail 1 .       HEAD

Benefits of energy pyramids

Fluoride Inhibitor Fluoride inhibits  enolase enzyme involved in the conversion of 2-phosphoglerate  to phosphoenol pyruvate.

Q. Is a viral infection treated with the same kind of drug that treats bacterial infections? The Antibacterial drugs, potent against a great variety of bacteria, are not effect

When did life appear on earth? It is estimated that the life on earth emerged about 3.5 billion years ago, thus 1 billion years after the formation of the planet.

Define Procedure for Measurement of pH? To ensure reliability of the pH readings, you should first calibrate the pH meter. You should adjust the pH meter so that the readings a