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

Illustrate about the complex partial seizures, State about the Complex part...

State about the Complex partial seizures Complex partial seizures, another type of focal seizure, originate most commonly in the temporal lobe. Complex partial seizures are cha

Ensure proper diet to control protein energy malnutrition, Ensure proper di...

Ensure proper diet to Control Protein Energy Malnutrition? PEM is preventable. It is a disease of the poor and the ignorant that suffer from social inequalities. Therefore, a h

Small for gestational age & intrauterine growth retardation, Define Small f...

Define Small for Gestational Age and Intrauterine Growth Retardation? Small for Gestational Age (SGA) is defined as infants affected by intrauterine growth restriction (IUGR).

Types of glials cells and their functions, Types of Glials Cells and their ...

Types of Glials Cells and their Functions In the nervous tissue, besides the nerve cells there is one other cell type -the neuroglia which is present in large numbers and occu

Explain the check screw access holes for closure, Check Screws- Check screw...

Check Screws- Check screw access holes for closure. If screw access holes are uncovered, such as the bar-retained dentures, make sure that are free from debris. If screws can b

Elaboration of yolk- reproduction, Normal 0 false false fal...

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

Explain the history of darwins finches, Explain the history of Darwin's Fin...

Explain the history of Darwin's Finches? The most well known evidence upon which Darwin based his theory was the distribution pattern of the Galapagos finches. The Beagle's voy

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