|
Servertime: 21:50:54
|
|
  
|
|
|
|
|
|
|
The Paramecium:
|
|
|
|
Paramecia, also known as Lady Slippers, due to their appearance, are a group of unicellular ciliate protozoa, which are commonly studied as a representative of the ciliate group, and range from about 50 to 350 ?m in length. Simple cilia cover the body, which allow the cell to move with a synchronous motion (like a caterpillar). There is also a deep oral groove containing inconspicuous compound oral cilia (as found in other peniculids) used to draw food inside. They generally feed on bacteria and other small cells. Osmoregulation is carried out by a pair of contractile vacuoles, which actively expel water from the cell absorbed by osmosis from their surroundings.
Paramecia are widespread in freshwater environments, and are especially common in scums. Certain single-celled eukaryotes, such as Paramecium, are examples for exceptions to the universality of the genetic code (translation systems where a few codons differ from the standard ones).
The paramecium approximates a prolate spheroid[1], rounded at the front and pointed at the back. The pellicle is a stiff but elastic membrane that gives the paramecium its definite shape. Covering the outer edge are whiplike structures, called cilia. On the side, beginning near the front end continuing down half way, is the oral groove, which collects food until it is swept into the cell mouth. There is an opening near the back end called the anal pore. The contractile vacuole and its radiating canals — referred to previously for osmoregulation of the organism, are also found on the outside of a paramecium. The paramecium is very commonly mistaken as a blepharisma.
The paramecium contains cytoplasm, trichocysts (“thread capsules”), the gullet, food vacuoles, the macronucleus.
|
|
|
|
|
|
|
|
Login:
|
|
|
Wikipedia Paramecia | SpieleCharts | kostenlose Browsergames
 
|
|
|
