Coelomoducts of molluscs, Biology

Coelomoducts of Molluscs

In Molluscs, like in Crustacea nephridia are absent. But certain of the larval pulmonates do possess protonephridia suggesting that they have been secondarily lost in molluscs. The excretory system is much more or less similar in all the groups of molluscs. In molluscs it is assumed that the two coelomic cavities meet dorsally to enclose the heart and their walls proliferate into germ cells. Their cavities through further differentiation give rise to gonad anteriorly, pericardial canal centrally and gonoduct posteriorly. The final segment, in addition had an excretory function. In Aplacophora the coelomoducts of adults contain a pair of tubular structures, leading from the coelomic cavity to the outside and primitively constitute the genital ducts. But in other molluscs modifications have arisen in the subsequent lines:

 i) There is a separation of genital and excretory organs.

ii) There is the development of fixed degree of asymmetry.

Posted Date: 2/4/2013 4:29:30 AM | Location : United States







Related Discussions:- Coelomoducts of molluscs, Assignment Help, Ask Question on Coelomoducts of molluscs, Get Answer, Expert's Help, Coelomoducts of molluscs Discussions

Write discussion on Coelomoducts of molluscs
Your posts are moderated
Related Questions
How much Protein should be taken for Management of Obesity? Adequate amount of proteins should be included in the diet to ensure proper metabolism and prevent weakness which is

ELECTROCONVULSIVE THERAPY: 1)  ConceptlMeaning of  Electroconvulsive Therapy  (ECT) Electroconvulsive Therapy (ECT) is a painless form of  electric therapy. It is called as ph

Define Interaction of niacin with other Nutrients? You may recall reading earlier that trypotophan present in dietary proteins is converted to niacin. There is an interdepend

Q. What is H shaped incision and what is it's purpose? This type of incision is especially useful for: The anterior maxilla or mandible. Accurately identified implant

Q. What is Autoclave sterilization? Word "autoclave" means self locking and is used to denote an apparatus that sterilizes by use of steam under pressure. It operates on same

What are stomata? How do these structures participate in the plant transpiration? Stomata (singular, stoma) are small specialized passages for water and gases there in the epid

In a Population that is in Hardy-Weinberg equilibrium, the frequency of the recessive Homozygous genotype is 0.49. The frequency of individuals Homozygous for the Dominant allele i

A study of broken rock Break open several rock specimens. Compare the appearance of freshly broken surfaces with the Heather-worn outside of the rock. The rocks may be safely b

Explain Dietetics Dietetics  has been defined as  the science and art of feeding individuals based  on the principles of  nutrition. It can also be  said  to  be  the "science

Q. Common Disorders of Coronary Heart Diseases? We shall deal with different types of heart diseases, their- etiology, symptoms, complications, as well as, nutrition and dietar