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

Describe the external features of the heart, Question 1 Describe the exter...

Question 1 Describe the external features of the heart. Add a note on circulation of blood within the heart Question 2 Discuss the major joints of thorax and pelvis Quest

Explain temperate deciduous forests-taiga and tundra, Explain Temperate Dec...

Explain Temperate Deciduous Forests-Taiga and tundra? Temperate deciduous forests are typified by the type of forests predominantly found in the eastern and northeastern Unit

Myocardial contractility, Inspiration decreases the pressure in the central...

Inspiration decreases the pressure in the central veins and thus increases the pressure gradient between the peripheral and central veins thus augmenting venous return. Skeletal mu

Infectious canine hepatitis, Infectious canine hepatitis The disease i...

Infectious canine hepatitis The disease is caused by type-1 canine Adenovirus in the family Adenoviridae. The disease appears in pups as peracute, acute, and mild. The clinica

Explain the consequences of malnutrition, Explain the Consequences of Malnu...

Explain the Consequences of Malnutrition? Malnutrition manifests itself in terms of illness and death in all age groups. Children, pregnant women, nursing mothers and elderly a

What purpose does sleep serve for the brain, What purpose does sleep serve ...

What purpose does sleep serve for the brain? A. We don't yet know full answer to this fundamental question however neuroscience is providing intriguing clues. It's increasingly

Explain about the glycemic index (gi), Explain about the Glycemic Index (GI...

Explain about the Glycemic Index (GI)? In the previous sections, we have studied that some carbohydrates are rapidly digested and absorbed, some are digested slowly while some

What is metachronal wave. describe., What is Metachronal wave? Describe. ...

What is Metachronal wave? Describe. During the coordination of the ciliary movement, bands, or groups of cilia, are at different stages of their beating pattern, and this creat

What chromosome condition is created, Following fertilization by a normal s...

Following fertilization by a normal sperm, what chromosome condition is created?

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