Ecological adaptation in animals to aquatic environment, Biology

Ecological adaptation in animals to aquatic environment

In the aquatic environment animals are confronted with the problem of excess water. Freshwater and marine animals try to maintain water balance in quite different ways. On account of the difference in the osmotic pressure between body fluids of aquatic organisms and their surrounding fluids aquatic organisms have developed osmoregulatory mechanism to deal with this problem. The salt content to the body fluids in freshwater animals is relatively high as compared to the surrounding water medium. Hence, the water tends to diffuse continuously into the body. Extra water from the body needs to be removed frequently. Most aquatic animals (e.g. protozoans and fishes) excrete the extra amount of water from the body by osmoregulation. Protozoa employ contractile vacuoles and other multicellular invertebrates and chordates use excretory organs such as nephridia and kidney (Figure shown below).

2251_fish adaptations.jpg

In marine animals the situation is just the opposite. The concentration of salts in the body fluids is low as compared to the surrounding medium (i.e. hypotonic). Under these conditions the body tends to loose water. But through metabolic osmoregulation water is retained in the body and salt is excreted. Animals vary widely in their salinity tolerance. Organisms which have a narrow tolerance and cannot withstand salinity fluctuation are called stemhaline. Organisms which can survive under a wide range of salinity conditions are termed euryhaliie. Usually animals inhabiting cooler fresh water and marine environments tend to have large body size except in a few cases such as diatoms and sea urchins which have relatively larger sizes in warmer waters.

 

Posted Date: 12/11/2012 1:09:58 AM | Location : United States







Related Discussions:- Ecological adaptation in animals to aquatic environment, Assignment Help, Ask Question on Ecological adaptation in animals to aquatic environment, Get Answer, Expert's Help, Ecological adaptation in animals to aquatic environment Discussions

Write discussion on Ecological adaptation in animals to aquatic environment
Your posts are moderated
Related Questions
Where does cartilage occur in a joint and what it its function? Cartilage might be found covering the surface of bones where they meet in a movable joint. Cartilage decreases f

In diabetes mellitus counsellor help the diabetic patient to cope up with the stress and take own decision for their treatment and life style changes. Decision making  capacity of

What are respiratory pigments? What is the respiratory pigment present in some arthropods? Which is the analogous molecule in humans? Respiratory pigments are molecules able t

How is gas exchange done in flatworms? Platyhelminthes exchange gases exclusively by diffusion by their body surface. This is only possible because all cells are localized rela

Disorder of Parathyroid Function: The disorders of parathyroid function may  either  lead  to increased production or decreased production of parathormone.  Hypoparathyroid

Q. How to investigate aortic stenosis by Echo Cardiography? 2D Echo cardiogram shows the number of cusps. But presence of raphae and distorted anatomy due to calcification may

Exudate gums Most exudates gums come from compounds  produced when the plant is wounded and these substances seal the wound. Most widely used exudate gum is 'gum Arabic' exuded

How do the plants classify according to their photoperiodism-based flowering? According to their photoperiodism-based the flowering plants classify as long-day plants, those th

Explain Basal Metabolism Rate (BMR) - Ageing? From age 25 years, the basal metabolism decreases by about 2 percent for each decade due to the increasing proportion of body fat

In glycoproteins, two main parts of oligosaccharide linkages exist: a) An O-linked oligosaccharides attached to the protein by O-glycosidic bonds, to the OH groups of serine or