Type specimen of class enteropneusta, Biology

Assignment Help:

Q. Type specimen of class enteropneusta?

Examine the specimen and note the following features:

1. Balanoglossus has a soft, elongated, worm-like body which has a ciliated surface.

2. Body length reaches 10-50 cms and is divided into short conical proboscis, , collar and long trunk.

3. Proboscis is cylindrical, tapering and muscular. Near the base is a proboscis pore which is the opening of the coelom (present within the proboscis) to the exterior.

4: Collar is a short, cylindrical, muscular band enclosing a pair of coelomic cavities (collar coelom). The collar opens by a pair of collar pores on the dorsal ; surface. The rim of the collar encloses the mouth which is permanently open. ,

5. The trunk is superficially ringed and divided into 3 parts (a) anterior branchiogenital part containing genital ridge that carry gonads. This part can , be demarcated from the outside as it has gill-slits but the contents cannot be seen without dissection. (b) hepatic region. (c) the posterior end which is the trunk region.

6. The mouth lies at the base of proboscis and is encircled by the edge of the collar.

7. In the hepatic region are present double rows of hepatic caeca.

8. Alimentary canal is straight and anus is at the end of the trunk. (Sexes are separate and fertilization is external. Development includes a free swimming pelagic larva called tornaria larva.)


Related Discussions:- Type specimen of class enteropneusta

Define metabolic response to food - requirement of energy, Define Metabolic...

Define Metabolic response to food - Requirement of Energy? Eating requires energy for the ingestion and digestion of food, and for the absorption, transport, inter conversion,

Phylum protozoa, PHYLUM  PROTOZOA Definition  and  Introduction  ...

PHYLUM  PROTOZOA Definition  and  Introduction  All  unicellular ( or  acellular )  eukaryotic  animals. Most  primitive (Gr. Protos = first=zoon= animals ) organisms

Heat exchangers, Normal 0 false false false EN-IN X-N...

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

What is a phenotype, What is a phenotype? A phenotype is each observabl...

What is a phenotype? A phenotype is each observable characteristic of a living being conditioned by its genes. Some phenotypes may be changed by nongenetic factors (for instanc

Pulsatile perfusion-type of blood pump, Pulsatile Perfusion: Conventional...

Pulsatile Perfusion: Conventional pumps give continuous flow with very little pulsatile property. Pulsatile perfusion is likely to result in better post operative renal and cardi

What is the important condition for a protein, Q. What is the important con...

Q. What is the important condition for a protein to be identical to another protein? For a protein to be identical to another protein it is necessary for the sequence of amino

Preet, what is microbiology

what is microbiology

What are the main functions of the bacterial flora, What are the main funct...

What are the main functions of the bacterial flora within the human gut? Bacteria that live inside the gut have great significance in digestion. Some polysaccharides like cellu

State the prevention of campylobacteriosis diseases, State the prevention o...

State the prevention of Campylobacteriosis Prevention: the various ways to prevent campylobacteriosis are: Wash hands before preparing foods. Wash hands immediatel

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