Metazoa, Biology

Assignment Help:

Metazoa

In the two kingdom classification, the unicellular 'animals' used to be clubbed together under a single phylum Protozoa that constituted sub-kingdom - Protozoa. The rest of the animals, all multicellular, were grouped under the sub-kingdom Metazoa under various phyla (the corresponding grouping for plants was Protophyta and Metaphyta). However, under the present concept of Five Kingdom Classification, this grouping has no relevance. Still, we often continue to use the term Metazoa to refer to the Animalia of the five kingdom classification. In this we start with an explanation of the levels of body organization in animals and the basic animal body plan. However, diverse the different invertebrates and vertebrates may appear to the eye, it is possible to group them in four master body plans.

These are the unicellular plan, the cell aggregate plan, blind sac plan and tube within a tube plan. The protozoan fall into the first category and the rest three structural plans are seen in the metazoans. We next list out the characteristic features of metazoans. We shall also discuss those features that are considered of fundamental importance for describing and understanding the structure and classification of any animal. These characters are:

  • Cleavage patterns and number of germ layers it has been derived from
  • Its body symmetry
  • Nature of body cavity
  •  Segmentation and cephalisation

 


Related Discussions:- Metazoa

What are the two mains divisions of the chordate phylum, What are the two m...

What are the two mains divisions of the chordate phylum? Chordates are separated into protochordates (cephalochordates and urochordates) and vertebrates. Life Kingdoms Revi

Disposal of microorganisms, Disposal : You must always sterilize cultures ...

Disposal : You must always sterilize cultures and contaminated instruments and glassware before disposing them of or before washing-up. Usually, you can do this by autoclaving or

Procedure for estimation of vitamin c - colorimetric method, Define Procedu...

Define Procedure for estimation of vitamin c - colorimetric method? Carry out the experiment following the instructions given herewith: 1. Prepare a series of tubes for blan

Management of respiratory failure, Management Goals Improve ...

Management Goals Improve oxygenations and ventilation to restore the person/s Pa 2 O 2 and PaCO 2 , to their previous levels.  Understand the underlying cause.

Isospora, ciclo vital de la isospora belli

ciclo vital de la isospora belli

Surface Processes on Earth, Which of the following is not a type of mass mo...

Which of the following is not a type of mass movement that results from the force of gravity? A. Landslide B. Creep C. Deflation D. Mudflow

Chemical stress - atmospheric imbalances, Chemical Stress - Atmospheric imb...

Chemical Stress - Atmospheric imbalances At least two components of the environment, oxygen and carbon dioxide that plants require are predominantly in the gaseous form. As yo

Define the effect of deficiency of vitamin c, Define the effect of Deficien...

Define the effect of Deficiency of Vitamin C? Severe ascorbic acid deficiency results in the development of the disease known as scurvy, three important manifestations of scur

Stentless devices -biological valves, Stentless Devices : A bioprosthesis...

Stentless Devices : A bioprosthesis mounted on a stent reduces the effective orifice area (EOA). The newer version (third generation) stentless gluteraldehyde preserved porcine v

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

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