Protozoans - body form, Biology

Protozoans - Body Form

The protozoan body is usually bound only by the cell membrane called plasmalemma. In some protozoans such as in ciliates the rigidity and the flexibility of the body is maintained by a cytoskeleton located immediately below the cell membrane which together with it forms the pellicle. The cytoskeleton is composed of filamentous proteins, microtubules or vesicles or a combinations of all three. In many protozoans like dinoflagellates, spore forming protozoans and. ciliates, vesicles occur below the cell membrane as flattened more or less continuous layer referred to as alveoli. They help to form a rigid skeleton.

1039_Protozoans - Body Form.png

                                                       Figure: Endoskeletons of Protozoans

A) Filamentous proteins form dense mesh called epiplasm Eg. Euglena and some ciliates
B) Micro tubular corset in flagellates, in spore forming protozoa and some ciliates
C) Axial skeleton of micro tubes
D) Axopod microtubules radiate like stars from centroplast
E) 'Empty' alveoli of ciliates
F) Cellulose plates in alveoli of dinoflagellates form rigid skeleton.

Exoskeletons secreted onto the outer surface of the cell are also seen in a large number of protozoans. These protozoans secrete layers of certain organic materials like gelatin, cellulose or tectin (a mucus like substance) around their plasmalemma. Some secrete an organic matrix containing minerals like silica or calcium carbonate. Often foreign bodies such as sand particles also get mixed up with the organic matrix to strengthen it. These chemicals organise to form theca, shell, lorica or cyst in different protozoans to provide protection.

Posted Date: 1/12/2013 5:15:59 AM | Location : United States







Related Discussions:- Protozoans - body form, Assignment Help, Ask Question on Protozoans - body form, Get Answer, Expert's Help, Protozoans - body form Discussions

Write discussion on Protozoans - body form
Your posts are moderated
Related Questions
Poultry birds are affected with many types of ailments; broadly these are classified on the basis of etiology as non-infectious and infectious conditions. Non-infectious diseases a

The field of  dietetics can be related to: Nutrition care and intervention focused on the individual, and Nutrition care and intervention focused on the group.

Explain the Management of Renewable Resources? Since the human population has grown, human impacts on the resources that we use, like fisheries and forests, have continued to g

What are the analyses provided by the study of human age pyramids? The study of human age pyramids can give the following analyses: proportion of individuals at an economically

Sheep and goats The disease is readily transmissible to human being from goats, and is known as Malta fever, Mediterranean fever or undulant fever. The chief causal agent is B

Eye Drops Medication is instilled in the form of drops or ointment.   Purpose To dilate pupil e.g. Atropine 1 per cent, drosyn 5 per cent or 10 per cent  To c

What are the three main parts into which a neuron can be divided? What are their respective functions? The three mains parts into which a neuron can be didactically separated a

Yesterday, when Eric returned home from jogging, he was breathing heavily, sweating profusely, and complained that his legs ached and felt weak. He took a drink of Gatorade and too

What mechanism of regulation is utilized in maintaining homeostatic balance of sugar?

How to Planning the Daily Diet for Underweight Patients? As mentioned above you need to add calories gradually to the diet. A practical way of doing so is to take the present i