Ciliated protozoan, Biology

Assignment Help:

Ciliated Protozoan

Ciliates form the largest and the most homogenous group of protozoans. They are placed under one phylum Ciliophora and evidence indicates that its members share a common evolutionary history. There are more than 7200 species found in fresh and marine waters and the water film of soil. About one third of ciliates are ecto and endoparasites or commensals. The classic example of this phylum is the slipper shaped Paramecium. Other well known examples are Vorticella, Stentor, Didinium, Balantidium.

317_Ciliated Protozoan.png

Figure: Various ciliates. Vorlieella and Stentor sessile ciliates, Stentor can also release itself and swim about. Didinium a raptoral ciliate Tetrahymena, Acineta with bunches of tentacles.


All ciliates possess cilia for locomotion and for suspension feeding. Another (Organization) distinguishing feature is the presence of kinetosomes (ciliary basal body) and an associated complex anchorage system of fibrils connecting the kinetosomes in longitudinal rows. All of these make the subsurface ciliature or infraciliary system. Most ciliates have a mouth or cytostome and feed by sweeping particle laden water into the mouth. The cytostome and cytopharynx open into the food vacuole and undigested remains are expelled through a fixed spot. Another characteristic feature is the presence of 2 types of nuclei. One large macronucleus and one or more small micronuclei. The macronucleus is called the vegetative nucleus as it regulates the normal metabolic processes of the organism for mitotic division and for control of cellular differentiation.

It is required for protein synthesis. The amount of DNA that macronucleus contains is much more than what is present in micronucleus because of duplications following the formation of macronucleus from the micronucleus. The micronucleus on the other hand is small and rounded. It is diploid and more than one may be present, with little RNA. The micronucleus contains the genetic material responsible for genetic exchange during sexual reproduction and also for reforming the macronucleus. Ciliates reproduce asexually by transverse fission and sexually through conjugation which involves the exchange and fusion of micronuclei at the region of contact.


Related Discussions:- Ciliated protozoan

What are the muscle of the diaphragm, Would you expect the muscle fibers of...

Would you expect the muscle fibers of the tongue to be striated or smooth? What about the muscle of the diaphragm/ Explain your answer.

Manx cats are heterozygous for a dominant mutation, Manx cats are heterozyg...

Manx cats are heterozygous for a dominant mutation that results in no tails or very short tails, large hind legs and a distinctive gait. The mating of two Manx cats yields two Manx

How much nacl can be made using 30g of nacl, How much of a 10% w/v of nacl ...

How much of a 10% w/v of nacl can be made using 30g of nacl? Please show all steps.

Functions of citric acid cycle, Functions of Citric Acid Cycle The citr...

Functions of Citric Acid Cycle The citric acid cycle is an amphibolic pathway  i.e.  it  is involved in both anabolic and catabolic processes

What is the binding between two amino acids, Q. What is the binding between...

Q. What is the binding between two amino acids called? The chemical bond between two amino acids is called a peptide bond.

Circulatory system, Circulatory System Coelenterates and platyhelminth...

Circulatory System Coelenterates and platyhelminths nutrients in sponges, respiratory gases and waste materials can easily diffuse through the intercellular spaces. Though, in

Find human anatomy & physiology laboratory manual, I can not find Human Ana...

I can not find Human Anatomy & Physiology Laboratory manual 10th edition cat version by Marieb/mitchell in expertsmind homework help, I have the text book just need to make sure I

Explain other lipids in biological compound, Explain Other lipids in biolog...

Explain Other lipids in biological compound? Other Lipids :  Another important type of lipids are the steroids, with a basic structure consisting of four interconnecting carb

Explain why statement is logical in terms of kin selection, Biology once sa...

Biology once said why this statement is logical in terms of kin selection and use the coefficient of relatedness he'd be willing to lay down his life to save two brothers or eight

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