Metameric segment - segmentation, Biology

Assignment Help:

Metameric segment - Segmentation

On the other hand true metameric segment as best observed in annelids has separate schizocoelic body cavity of mesodermal origin in each segment. Individual segments are budded off in linear sequence from a proliferation region just in front of the posterior end. Segmented animals have a specialized anterior acron (prostomium) and posterior pygidium or telson both of which are not segments. In between there are a varying number of segments.

In near perfect segmentation, appendages, musculature, ganglion, nerves, blood vessels, coelom and all body organs are replicated in each segment. This arrangement is best seen in annelids. In chordates, segmentation is usually apparent in the axial skeleton. Muscles and nerves. Why did segmentation evolve in animal groups? What advantages does it confer on the animals in which it is seen? Let us examine this a little closely. The most important advantage is that segmentation divides a body into a series of compartments, each of which can be regulated almost independently. This in a way provided the framework for specialization. In colonial animals this specialization is seen in polymorphism of zooids while in segmented animals regional specialization of segments occurs.


Related Discussions:- Metameric segment - segmentation

How is gas exchange done in flatworms, How is gas exchange done in flatworm...

How is gas exchange done in flatworms? Platyhelminthes exchange gases exclusively by diffusion by their body surface. This is only possible because all cells are localized rela

Define about the paper electrophoresis, Define about the Paper electrophore...

Define about the Paper electrophoresis? In paper electrophoresis the sample is applied to a point on a strip of filter paper or cellulose acetate moistened with buffer solution

Why dietary supplements do not speed up a child''s growth, Why Dietary supp...

Why Dietary supplements do not speed up a child's growth? Dietary supplements do not "speed up" a child's growth and development: There is no scientific evidence that me

What is cytosolic cyclic amp, What is cytosolic cyclic AMP Healthy Pers...

What is cytosolic cyclic AMP Healthy Person P takes a new drug that is a member of a drug family that results in  constant levels of cytosolic cyclic AMP (cAMP) in one and only

Explain about the ocular haemodynamics, Explain about the Ocular Haemodynam...

Explain about the Ocular Haemodynamics. The pressure in the ocular arteries can be measured by optical ophthalmodynamometer. The intraocular pressure is raised to the level tha

The Endocrine system, What are the two models that explain Mechanism of Hor...

What are the two models that explain Mechanism of Hormone Action on their target?

Secretion of parathormone and calcium blood level, Q. What is the relation ...

Q. What is the relation between secretion of parathormone and the calcium blood level? The parathormone increases the calcium blood level since it stimulates the resorption (re

Explain the term tracheostomy, Explain the term Tracheostomy ? If the d...

Explain the term Tracheostomy ? If the duration of mechanical ventilation is likely to be prolonged, it is wise to do an early tracheostomy. Otherwise, a tracheostomy is usuall

Pollutions, what is detergent pollution and it''s effects and causes

what is detergent pollution and it''s effects and causes

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