Encystment – protozoan, Biology

Encystment – Protozoan

Encystment is characteristic of the life cycle of many protozoan. The protozoan secretes a thickened envelope (cyst) around itself and becomes inactive with almost a complete shutdown of metabolic activity. This protective cyst is resistant to either desiccation or low temperatures and enables the animal to pass through unfavorable environmental conditions like food deficiency, desiccation, decreased oxygen concentration, pH, etc.

Reproductive phases such as fission, budding and syngamy may occur inside the cysts of some species Encystment is however, not found or is very rare in marine species. Protozoa may be dispersed long distances in either the motile or encysted stages. Water currents, wind, mud, debris, the bodies of birds and animals are common agents of dispersal.

Cysts of some soil inhabiting and freshwater protozoa show amazing durability. The soil ciliate Colpoda has been known to survive in dried soil for up to 38 years On the other hand not all cysts are as durable. Cysts of Entamoeba histolytica can tolerate the acidic medium of the stomach but do not survive desiccation, temperature above 50°C or sunlight. A return of favorable conditions initiates excystment (escape from cysts) in those protozoa in which the cysts are a resistant stage.

Posted Date: 1/12/2013 6:26:27 AM | Location : United States







Related Discussions:- Encystment – protozoan, Assignment Help, Ask Question on Encystment – protozoan, Get Answer, Expert's Help, Encystment – protozoan Discussions

Write discussion on Encystment – protozoan
Your posts are moderated
Related Questions
Gene  is the fundamental physical and functional unit of the heredity (generally DNA, Some of the organisms have RNA a gene). A gene is an ordered series of nucleotides located in

Q. How can the blood coagulation (clotting) process be described? Blood clotting encompasses a sequence of chemical reactions whose respective products are enzymes that catalyz

Most bacteria are anaerobic. If a bacterium were to produce the same amount of ATP within a minute as a cell extracted from your skeletal muscle, what would that bacterium have to

Nursing Management The overall goals are that patient with RH fever will resume daily activities without Joint pain, reduce the risk of residual cardiac disease, and plan a

site of fertilistion in human

FAT METABOLISM Animals  digest  and utilize three main  types  of fatty compounds or lipids  neutral or true  fats ( triglycerides ),  phospholipids  and sterols. Endproducts

Breeding of crops with high levels of minerals, vitamins and proteins is called: 1. Somatic hybridisation 2. Biofortification 3. Biomagnification 4. Micropropagation

Q. How many ATP molecules are made after glycolysis? Glycolysis is a process similar to glucose degradation in fermentation it produces final balances two molecules of ATP for

What is the difference between octopuses and mussels regarding their circulatory systems? How does that difference influence the mobility of these animals? Cephalopod molluscs,

Dietary management during Myocardial Infarction? Patients who suffer from an attack of myocardial infarction are hospitalized and are usually kept under strict medical supervis