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

Functions of skeleton, FUNCTIONS OF SKELETON - 1.      Support. 2.  ...

FUNCTIONS OF SKELETON - 1.      Support. 2.      To give shape to the body. 3.      Protection of different organs. 4.       Site for muscle attachment. 5.       He

Explain the effect of deficiency of vitamin e, Explain the Effect of Defici...

Explain the Effect of Deficiency of Vitamin E? Fortunately, vitamin E deficiency in human is extremely rare. This may probably be due to its wide occurrence. in natural foods a

Respiration in adult amphibians and fishes, Q. Do amphibians have direct de...

Q. Do amphibians have direct development? In amphibians the embryonic development is indirect there is a larval stage. Q. How different are the respiration in adult amphibi

Explain ganongs potometer, For measuring the rate of transpiration of a twi...

For measuring the rate of transpiration of a twig using Ganong's potometer, learner A cuts the twig and fits it in the broad end of the water-filled potometer. Learner B cuts the t

Renin-angiotensin system, As heart failure sets in, there is activation of ...

As heart failure sets in, there is activation of RAS (Fig 2.1). Adrenergic stimulation of beta-1 receptors in juxtaglomerular apparatus of the kidneys results in release of renin.

Define biological hazards, Normal 0 false false false E...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Spirogyra, whats the meaning of asexual reproduction

whats the meaning of asexual reproduction

Bottleneck for external sources for health care, Bottleneck for External So...

Bottleneck for External Sources for Health Care The implementation bottlenecks arising out of funding by external sources have important implications for the resource allocati

Congestive heart failure, In native-valve IE, acute CHF occurs more frequen...

In native-valve IE, acute CHF occurs more frequently in aortic-valve infections (29 per cent) than with mitral (20 per cent) or tricuspid disease (8 per cent). CHF may develop acut

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