2.8+Micro-organisms

Paramecium
 Paramecium are single celled organisms that live in water, often found in ponds. The do not photosynthesis and need to 'eat' to get nutrients and energy. The paramecium is an oval, slipper shaped micro-organism, rounded at the front/top and pointed at the back/bottom. The pellicle, a stiff but elastic membrane that gives the paramecium a definite shape but allows some small changes. Covering the pellicle are many tiny hairs, called cilia. On the side beginning near the front end and continuing half way down is the oral groove. The rear opening is called the anal pore. The contractile vacuole and the radiating canals are also found on the outside of a paramecium. Inside the paramecium is cytoplasm, trichocysts, the gullet, food vacuoles, the macronucleus, and the micronucleus. Study the drawing below.



Cilia - hair like appendages that help the paramecium move food into the oral groove

Oral Groove - collects and directs food into the cell mouth

Cell Mouth - opening for food

Anal Pore - disposes of waste

Contractile Vacuole - contracts and forces extra water out of the cell

Cytoplasm - intercellular fluid needed to contain vital cell parts

Gullet - forms food vacuoles

Food Vacuole - storage pocket for food

Macronucleus - larger nucleus which performs normal cell functions

Micronucleus - smaller nucleus which is responsible for cell division.

=Paramecium and osmosis = media type="youtube" key="iG6Dd3COug4" width="560" height="315"

=Paramecium Feeding= media type="youtube" key="a4aZE5FQ284" width="560" height="315"

=**Paramecium and Contractile Vacuoles**= Paramecium live in a hypertonic environment. This means that the inside of the paramecium has a higher concentration of salt than the outside. This means that water will constantly go in to the paramecium from the outside environment. If the paramecium couldn't control the amount of water entering it would swell up like a balloon until it bursts. They control the water content in their tiny bodies by using a contractile vacuole. Water moves in to the vacuole via tiny tubules. The vacuole then contracts forcing water back out in to the environment. media type="youtube" key="4z98WIeNtjM" width="560" height="315" <span style="background-color: #eeeeee; color: #4b4b4b; display: block; font-family: Helvetica,Arial,sans-serif; font-size: 12px;">