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

Explain taxonomy - modern trends in animal taxonomy, Explain Taxonomy - Mod...

Explain Taxonomy - Modern Trends in Animal Taxonomy The term taxonomy which is derived from the Greek word 'taxis', meaning order or arrangement and nbmos ' meaning law, deals

Atp, what is atp explain in detail?

what is atp explain in detail?

State the active hyperemia, Which of the following is true for active hyper...

Which of the following is true for active hyperemia, a local control mechanism within the circulatory system? A. There will be a decrease in force developed by smooth muscles s

Illustrate basic working of pineal gland, Q. What is the pineal gland? ...

Q. What is the pineal gland? The pineal gland also known as epiphysis or pineal body is situated centrally in the head. It secretes the hormone melatonin. A hormone produced at

Explain ganciclovir, Ganciclovir  (Cytovene) IV ganciclovir is approved...

Ganciclovir  (Cytovene) IV ganciclovir is approved for both induction and maintenance treatment of cytomegalovirus (CMV) retinitis in immunocompromised patients and for prevent

Events after sperm and egg fusion, Events after Sperm and Egg Fusion ...

Events after Sperm and Egg Fusion The entry of the sperm into the egg activates the egg. The activation of egg results in two types of responses. (1) The early responses a

Explain assessment of iron status - serum ferritin, Explain assessment of i...

Explain assessment of iron status - Serum Ferritin? Serum Ferritin: This method is indicative of iron stores. As we know, a long term negative iron balance first results in dep

Explain signal hypothesis, A classical secretory protein vary from a cytoso...

A classical secretory protein vary from a cytosolic protein by having a sequence about 13-35 amino acids long at its N-terminal end called as a signal peptide or signal sequence.

Eyeball - choroid, CHOROI D - Thin, net like made up of connective ...

CHOROI D - Thin, net like made up of connective tissue, rich in blood vessels. Pigment present, red in rabbit, brown or black in man. It reduces internal reflection.

Types of disease, TYPES OF DISEASE    ...

TYPES OF DISEASE     communicable Caused by infective agents disease

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