Paramecium caudatum-class Ciliata

A definite slipper shape

• 1. Pellicle present
• 2. Endoplasm and ectoplam make up cytoplasm
• 3. Two nuclei present: micronucleus and macronucleus
• 4. Two contractile vacoules present: anterior and posterior

The definite shape makes visible anterior and posterior regions of the organism. In addition an oral groove suggests an oral surface as well as aboral surface.

Same as amoeba and euglena no respitory structure and takes place by simple diffusion

Same as amoeba and euglena but the exception is that there are two contractile vacuoles.

• 1. Movement is by permanent locamotary structures called cila.
• 2. Each cilium is connected to a basal granule.
• 3. All basal granules are inter-connected just benneath the pellicle.
• 4. The entire locomotary "system" is referred to as a NEUROMOTOR SYSTEM.

• 1. Ingestion is at a single point via the oral groove then the mouth which leads to a cytopharynx.
• 2. At the end of cytopharynx a food vacuole is formed into this food vacoule is poured digestive enzymes as such digestion is INTRA-CELLUAR.
• 3. Undigested food material is egested via an opening called Anal pore or cytopyge.

• 1. Reproduces a-sexually and "sexually"
• 2. A-sexual reproduction is transverse binary fission (because its by width, the short side).
• 3. The MICRONUCLEUS divides into two micronuclei by mitosis.
• 4. The MACRONUCLEUS simply divides into two micronuclei without mitotic or meiotic cell division (amitotically).

The macronucleus does not have anything to do with a-sexual or sexual reproduction.

• 1. For of "sexual" reproduction
• 2. Two paramecium come together as mating conjugants.
• 3. Macronucleus degenerates in both paramecium.
• 4. In each paramecium the micronucleus form "male" and "female" pronuclei.
• 5. There is an exchange of "male" pronucleus between conjugants. The result is the formation of a zygotic nucleus.
• 6. There is no exchange of cytoplasmic material, conjugation is not a true form of sexual reproduction.

The significance of this is that it begins the differentiation of sex among living organisms