Organs in animal - excretion, Biology

Assignment Help:

Organs in animal - Excretion

In all the other animal groups, there are discrete organs which function in osmotic regulation, ionic regulation and nitrogen excretion. These are the contractile vacuoles of protozoans and poriferans, the nephridia of flatworms, roundworms and annelids, the green glands of crustaceans, the coxal glands of arachnids, the malpighian tubules of insects and the metanephric kidney of vertebrates. Depending on whether the nephridial tubule is closed at the inner end or opens into the coelom by funnel shaped structure called nephrostome, nephridia are respectively termed as protonephrldia or metanephridia.

The excretory organs of molluscs, crustaceans and arachnids are actually modified coelomoducts and hence are not true nephridia. With the exception of the contractile vacuoles of protozoans and sponges, the excretory organs are either tubules or aggregates of numerous tubules.


Related Discussions:- Organs in animal - excretion

Explain glomerular filtration in human nephrons, A horticulturist keeps Chr...

A horticulturist keeps Chrysanthemum plants in short-day conditions during long-day season. State its effect on flowering. Specify the role of phytochrome included. Explain glom

Define species of biological species concept, Define species according to t...

Define species according to the biological species concept. What two problems often make this definition impractical?

Renewable energy sources, Capacity to do work is known as energy. It is ver...

Capacity to do work is known as energy. It is very important input for all our activities like cooking food, driving vehicle and running industries. The most important challenge th

Describe nerve cells, In eukaryotes possibly the most rapid and complex sig...

In eukaryotes possibly the most rapid and complex signaling is mediated through nerve impulses.  The Nerve  cells  (neurons)  consist  of  a cell  body  with  numerous projections

Mechanisms of hemorrhage contention, Q. What are the mechanisms of hemorrha...

Q. What are the mechanisms of hemorrhage contention called? The physiological mechanisms of hemorrhage contention one of them is blood clotting are generically named hemostatic

Measuring ecosystem diversity, Measuring ecosystem diversity is not easy, a...

Measuring ecosystem diversity is not easy, and ther e is no definite index for its measurement. It is generally assessed by the measure of species diversity in an ecosystem, often

Define the symptoms in bone marrow of pernicious anaemia, Define the sympto...

Define the symptoms in Bone marrow of pernicious anaemia? The nucleated red cells of the marrow are greatly increased.  The successive nucleated cell stages in erythropoiesis a

Define the concepts of lipids, Define the Concepts of Lipids? You have ...

Define the Concepts of Lipids? You have studied the classification of lipids in your theory lesson. Lipids, you learnt, are classified as simple, compound or derived lipids on

Extinction of a plant species, How could humans be disadvantaged by the ext...

How could humans be disadvantaged by the extinction of a plant species? The loss of a plant species may deprive humans of any beneficial substances (e.g. drugs) that the specie

Thermodynamics and cell shapes, Thermodynamics and Cell Shapes Why are...

Thermodynamics and Cell Shapes Why are protoplasts (cells devoid of cell wall) spherical? Why are most of the unicellular organisms (prokaryotes and eukaryotes) spherical? A s

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