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

Epithelial Cells, What are all teh parts of a simple ciliated columnar epit...

What are all teh parts of a simple ciliated columnar epithilial cell?

Eczema, E c z e m a It is inflammatory reaction of epidermal cells...

E c z e m a It is inflammatory reaction of epidermal cells to the substances to which these cells are sensitized. Such substances may be present either in the external or

What is eutrophication, What is eutrophication? Eutrophication is the p...

What is eutrophication? Eutrophication is the process of excessive enhancing of nutrients, like phosphate and nitrate, in water because of direct deposit of non treated sewage.

Explain brown fat and white adipose tissue - energy balance, Explain Brown ...

Explain Brown fat and white adipose tissue - energy balance? There are two kinds of adipose tissue - Brown Fat is located around the shoulder blades and kidneys, constituting 1

Radiographic evaluation - criteria for endosteal implants, Radiographic Eva...

Radiographic Evaluation - criteria for endosteal implants Surgical and interventional imaging involves imaging the patient  during and immediately after surgery and during the

How to investigate aortic stenosis by roentgenogram, Q. How to investigate ...

Q. How to investigate aortic stenosis by Roentgenogram? Cardiac enlargement does not occur in pure compensated aortic stenosis. Post stenotic dilatation of aorta may be seen. F

Describe the rationale behind sterilization, Q. Describe the rationale behi...

Q. Describe the rationale behind sterilization? Rationale for sterilization: Source of potential infection that exists in dental office include hands, saliva, nasal secretion,

Mycotic aneurysms, They result from septic embolization of vegetations to t...

They result from septic embolization of vegetations to the arterial vasa vasorum or the intraluminal space, with subsequent spread of infection through the intima and outward throu

Define functions of fluoride, Define Functions of fluoride? The only b...

Define Functions of fluoride? The only beneficial role demonstrated for fluoride is in reducing the prevalence and severity of dental caries in children and adults. This is en

What is inflammation, What is inflammation? Inflammation is the initial...

What is inflammation? Inflammation is the initial response of the unspecific defense system versus aggressions against the body (the aggressions might be caused by infectious p

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