Osmoregulation in marine non-chordate metazoans, Biology

Assignment Help:

Osmoregulation in Marine Non-Chordate Metazoans

Studies on the osmotic pressure of body fluids of marine organisms have displayed that their internal osmotic pressure is more or less similar to the sea water where they live. Marine invertebrates are isotonic with the seawater in which they live, but the ionic composition of their body fluids might be markedly different from that of the normal sea water. For instance the mesogloea of the coelentrates has high potassium and a low sulphate concentration than to the seawater in which they live. This is true of polychaetes and echinoderms as well. Marine and brackish water animals have isosmotic or slightly hyperosmotic body fluid. Production of an isosmotic or a little hyperosmotic urine may cause the loss of valuable electrolytes. Hence, there is a continuous regulation of electrolytes of body fluids. Such type of regulation is achieved by several ways. Surface areas permeable to water and ions are usually reduced to a minimum Water pumps in the form of contractile vacuoles and nephridial tubules are present. But the most significant machinery that remains a part of every cell is the active transport. In certain organs like gills of crustaceans, highly specialised tissues exploit the capacity of active transport of large amounts of salts. In decapod crustaceans and cephalopods, ionic regulation might extend to every ion. For example, in these organisms calcium and potassium are more concentrated in body fluids than in the external medium, while magnesium, sulphate and chloride are less concentrated. Reduction in anion concentration like sulphate is compensated by an increase in sodium concentration. So in marine invertebrates including coelentrates, the internal medium has a specialised ionic composition quite different from that of external medium. Excretory organs play a role in ionic regulation.


Related Discussions:- Osmoregulation in marine non-chordate metazoans

Explain procedure for gram staining of bacterial cultures, Explain Procedur...

Explain Procedure for Gram Staining of Bacterial Cultures? Now carry out the exercise following the steps enumerated herewith. 1. Prepare bacterial smear on a clean, non-gre

Assisting in procedure of biopsy, ASSISTING IN PROCEDURE OF BIOPSY Bio...

ASSISTING IN PROCEDURE OF BIOPSY Biopsies are removal of a small piece of tissue for examination under microscope. Such examinations are called hist to pathological examina

Osmoregulation, explain osmoregulation in crustacean ?

explain osmoregulation in crustacean ?

Viruses.., are there non-parasitic viruses

are there non-parasitic viruses

What is transportation of sick newborn infants-heart disease, What is Trans...

What is Transportation of Sick Newborn Infants with Heart Disease Communication : The decision to transport a newborn to a tertiay referral centre with facilities for specia

Poultry and duck diseases-fowl pox, Fowl pox Fowl-pox is a highly infec...

Fowl pox Fowl-pox is a highly infectious disease of poultry, especially chickens and turkeys. Pheasants, ducks, geese and guineafowls also suffer from an infection similar to f

What is herbicide tolerant crops in ecological, Herbicide tolerant crops (H...

Herbicide tolerant crops (HTC) Increased use of the herbicides plant is tolerant to (describes ecological impact eg toxic residues in soil, runoff into waterways) Ther

Waste management in other species, W a s t e Management in other specie...

W a s t e Management in other species Solid and pellet nature of sheep and goat faecal matter make it easier to handle. This manure can easily be swept off the floors and d

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