Polychaete, mollusca and echinodermata, Biology

Assignment Help:

Polychaete, Mollusca and Echinodermata

Polychaete and Mollusca

The polychaetes have a trochophore larva. A common trochophore larva is top shaped bearing a tuft of cilia at the apical end and a band or girdle of cilia termed as the prototroch which rings the body about one third to one half the distance from the apical tuft. It is the swimming organ and collects suspended food particles. The gut is a complete tube and mouth opens posterior to prototroch. Trochophore larva is characteristic of polychaetes and molluscs.

Echinodermata

Almost all larvae of echinoderms are planktonic. Not like the adults the larvae do not show pentamerous symmetry and do not have tube feet. They move by bands of cilia over the body and its projections. After a time of planktonic life a rudimentary skeleton starts to form and the larvae sink to the bottom to develop the adult shape and form.


Related Discussions:- Polychaete, mollusca and echinodermata

What are cotyledons, What are cotyledons? Cotyledons, or seed leaves, a...

What are cotyledons? Cotyledons, or seed leaves, are structures formed by the embryo of angiosperms to absorb nutrients from the endosperm and to keep and transfer these nutrie

What is the etiological agent, What is the etiological agent and the main m...

What is the etiological agent and the main manifestations of cholera? Cholera is a bacterial disease caused by the Vibrio cholerae. The disease is transmitted by fecal-oral rou

Name the phases into which hiv infection is often divided, What are the thr...

What are the three phases into which the HIV infection is often divided? The HIV infection is often separated into three phases: the acute phase, from the infection to 1 until

Explain the vitamin k dependent proteins, Explain the Vitamin K dependent p...

Explain the Vitamin K dependent proteins? The four vitamin K-dependent procoagulants (factor II or prothrombin, and factors VII, IX, and X), about which we studied above, are s

Death, DE A T H - It is terminal end of the degeneration changes of ...

DE A T H - It is terminal end of the degeneration changes of old age. Death occurs when vescular system & respiratory system stop working. Failure of nervous system ma

What are the major functions of the blood, Q What are the major functions o...

Q What are the major functions of the blood? The blood is a means of substance transportation throughout the body. The blood distributes hormones, nutrients, oxygen, cells and

Assisting in procedure of biopsy, ASSISTING IN PROCEDURE OF BIOPSY Bio...

ASSISTING IN PROCEDURE OF BIOPSY Biopsies are removal of a small piece of tissue for examination under microscope. Such examinations are called hist to pathological examina

Offspring, #q1. If offspring exhibit a 3:1 phenotypic ratio, what are the g...

#q1. If offspring exhibit a 3:1 phenotypic ratio, what are the genotypes of a parent?uestion..

How hyperventilation affect blood ph, Freediving is an activity in which a ...

Freediving is an activity in which a person dives, sometimes to great depth, without the use of scuba gear. The diver must hold his or her breath for the duration of the dive. (The

Tidal energy and its advantages and disadvantages, Tidal energy The per...

Tidal energy The periodic rise and fall of water level of sea is called tides which are caused by gravitational effect of moon combined with the rotation of the earth. This var

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