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

Carbohydrates, Carbohydrates are the next important nutrients as they have ...

Carbohydrates are the next important nutrients as they have to perform a variety of functions such as: 1) Provide major source of energy 2) Breakdown of fatty acids and preve

Development of heart in amphibians, Development of Heart in Amphibians ...

Development of Heart in Amphibians The heart and the surrounding pericardial cavity build up from lateral mesoderm. After gastrulation, the mesodermal mantles carry on to gro

What is alkaline phosphatase, Question 1 Discuss the quantitative methods ...

Question 1 Discuss the quantitative methods for the estimation of urinary proteins. What are the instructions to be given to a patient while collecting urine for biochemical exami

Explain about atrial septal defect, Explain about Atrial Septal Defect (ASD...

Explain about Atrial Septal Defect (ASD) ? ASD occurs as an isolated anomaly in 5- 10 per cent of all CHDs. These communications occur in four sites i.e. in the central portion

What are dna ligases, What are DNA ligases? How do these enzymes participat...

What are DNA ligases? How do these enzymes participate in the recombinant DNA technology? The DNA ligases are enzymes specialized in tying the complementary DNA chains that for

Alkaline phosphatase, Alkaline Phosphatase is an enzyme which catalyzes th...

Alkaline Phosphatase is an enzyme which catalyzes the hydrolysis of the phosphomonoesters of the 5' nucleotides. It is used to dephosphorylate (remove phosphate groups from) the 5

Define about the sporocyst larva, Define about the Sporocyst Larva? Sp...

Define about the Sporocyst Larva? Sporocyst is the second larval stage in the life cycle of F. hepatica. It develops from the miracidium larva within the pulmonary chamber of

State the term - multiple sclerosis, Explain about the Multiple Sclerosis ...

Explain about the Multiple Sclerosis This is a disease characterised by the loss of myelin, largely in motor tracts but also in sensory tracts. The loss of myelin is not unifor

What are the nutritional components of the foods we consume, What are the n...

What are the nutritional components of the foods we consume? The foods that we consume are composed of varying quantities of the following nutritionally important components:

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