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

Opiate narcotics - psychological drug dependence, OPI A T E NARCOTICS - ...

OPI A T E NARCOTICS - They suppress brain activity and relieve pain popularly known as pain killers. They are sedative and astringent in nature. An astringent cause

What are the functions of the eyelids, What are the functions of the Eyelid...

What are the functions of the Eyelids? Functions of the Eyelids: The eyelid makes the outer most layers, covering the eye. Because of its strategic position, the eyelid s

How can nutrients are classified, According to their functions how can nutr...

According to their functions how can nutrients are classified? One possible and utile functional classification for nutrients is the one that divides them into energetic, struc

Which are the respiratory muscles in mammals, Q. Which are the respiratory ...

Q. Which are the respiratory muscles in mammals? In mammals the muscles that participate in the breathing process are the diaphragm and the intercostal muscles, in respiratory

Define biocompatible material, Define each term and give an example of an a...

Define each term and give an example of an application that uses the following: a. Biocompatible material b. Biodegradable material c. Biomimetic

How many distinct hexapeptides made from 20 amino acids, How many distinct ...

How many distinct hexapeptides can be made from 20 amino acids?

Explain effect of nutrient supplements on drugs, Explain Effect of Nutrient...

Explain Effect of Nutrient Supplements on Drugs? A nutrient or nutrient supplement can alter the pharmacological action of a drug by enhancing the drug effect or by opposing it

Define natural gums - hydrocolloids, Natural Gums These are derived fro...

Natural Gums These are derived from various plant as well as microbial sources and are divided into the following four basic categories: 1.  Seaweed gums:   Agar, Alginate,

Fertilization - pre-embryonic development, Fertilization - Pre-Embryonic De...

Fertilization - Pre-Embryonic Development Ovulation generally takes place between 9th to 14th day after the end of last menstrual period. Fertilization of oocyte initiates dev

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