Malpighian tubules, Biology

Malpighian Tubules

Other arthropods like insects and myriapods and arachnids have Malpighian tubules, the outgrowths of alimentary canal like excretory organs. Malpighian tubules are totally new structures, containing no resemblance either to nephridia or coelomoducts. Generally, the Malpighian tubules that are composed of single layered epithelium and are bathed in the blood of haemocoel. By the procedure of active secretion water passes into the lumen of Malpighian tubule together with nitrogenous wastes and dissolved salts. The secretion essentially takes place in the distal parts of the tubules. The proximal part of the tubule as well as the rectum is the sites of absorption. Most of the terrestrial arthropods excrete uric acid. The reabsorption of water results in the precipitation of urate crystals as nitrogenous waste, therefore the animals are termed as uricotelic. Peripatus which is also terrestrial lacks Malpighian tubules. Nevertheless it is uricotelic. The excretion of uric acid is acquired from the intestinal epithelium into the intestinal lumen. It is removed from the intestine within a peritrophic membrane which is sloughed off every 24 hours. There are also segmentally arranged coelomic excretory organs. The coelomoducts of Peripatus can be considered as vestigial organs of its aquatic ancestry, with a much reduced activity.

Posted Date: 2/4/2013 4:27:54 AM | Location : United States







Related Discussions:- Malpighian tubules, Assignment Help, Ask Question on Malpighian tubules, Get Answer, Expert's Help, Malpighian tubules Discussions

Write discussion on Malpighian tubules
Your posts are moderated
Related Questions
Quality control of feedstuffs Quality control is essential at all stages in the production of compound feed so that animals could get wholesome balanced and nutritious feed. Th

Explain about the Renal and Urogenital System? Various studies have shown a decrease in the creatinine and insulin clearance. Due to the changes in glomerular structure of the

Explain the Determination of Vitamin E DL-α-Tocopherol is oxidized with ferric chloride and the ferrous ions formed are measured colorimetrially with the aid of α,α'-dipyridyl

State in brief about respiration When we breathe in the air, our chest expands and air is taken in the lungs and when we breathe out chest returns to its resting position. This

DNA (deoxyribonucleic acid) is the molecule which are responsible for storing and transmitting the genetic information. DNA is a double- stranded molecule which is held together b

Define the role of riboflavin in Antioxidant Activity? Flavoproteins also have powerful antioxidant activity from their role as precursors to FMN and FAD. Among the FAD-requiri

Primary producers - Biotic Components The major primary producers of aquatic ecosystems (freshwater and marine) are various species of algae. In terrestrial ecosystems the ma

CONDUCTIO N OF IMPULSE - IN NON-MYELINATED AXONS - The impulse moves along the axon as local effect by altering the permeability of neighbouring Na +  channels and af

Vasa efferentia are the ductules leading from: 1. Testicular lobules to rete testis 2. Rete testis to vas deferens 3. Vas deferens to epididymis 4. Epididymis to urethra

Stress - Responses of Plants to Stress Let us recall what happens within the natural communities occupying the same habitat. The relative location of two plants may place them