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

Why does thermal inversion increases air pollution, Q. Why does thermal inv...

Q. Why does thermal inversion increases air pollution? What harm can thermal inversion cause to humans? The Thermal inversion confines at low altitude a layer of pollutants tha

Which harmone is not associated with male reproduction, Which of the below ...

Which of the below is NOT hormone associated with male reproductive physiology: a) Prolactin b) Testosterone c) Interstitial hormone d) Follicle-stimulating hormone

List the causes of implant failure, List the causes of implant failure due ...

List the causes of implant failure due to improper surgical technique and placement. Failure due to surgical techniques and improper placement: a) Off axis / severe angulati

Segments of environment:, Segments of Environment: The environment ...

Segments of Environment: The environment is not a simple distribution of gases but is highly complex and structured. It comprises of four segments:   Lithosphere

How is light from the sun transformed into chemical energy, How is light fr...

How is light from the sun transformed into chemical energy to be used by the living beings on earth? Light from the sun is transmitted into chemical energy contained in organic

Explain changes in gastrointestinal tract of infants, Explain changes in ga...

Explain changes in gastrointestinal tract of infants? A full term baby has the ability to digest simple proteins, carbohydrates and emulsified fats. In first 3-4 months, the p

Cell biology, Explain the functis of the main organelles in plant and anima...

Explain the functis of the main organelles in plant and animal cell as seen under the lightmicroscope

What is the endocrine function of the placenta, What is the endocrine funct...

What is the endocrine function of the placenta? The placenta besides being the organ by which the exchange of substances among the mother and the fetus is done also has the fun

How does the federal government regulate plant-incorporated, How does the f...

How does the federal government regulate plant-incorporated protectants and ensure their safe use in foods? EPA regulates the manufacture, sale and use of pesticides, containin

How is the brain involved in the immune system, How is the brain involved i...

How is the brain involved in the immune system? A. Immune cells that constitute body's biological defense against infections and toxins, have many things in common with nerve c

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