| Paramecium caudatum | |
|---|---|
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Chromalveolata |
| Phylum: | Ciliophora |
| Class: | Ciliatea |
| Order: | Peniculida |
| Family: | Parameciidae |
| Genus: | Paramecium |
| Species: | P. caudatum |
| Binomial name | |
| Paramecium caudatum Ehr. |
|
Paramecium caudatum[1] are unicellular organisms belonging to the genus of Paramecium of the phylum Ciliophora.[2] They they can reach 0.25mm in length and are covered with minute hair-like projections called cilia.[3] The cilia are used in locomotion and feeding.[2] They are often called slipper animalcules because of their slipper-like shape.[2]
P. caudatum feed on bacteria by driving them into the biosphereic presser valve with cilia.[2] Their natural habitat is fresh water.[3] They take in water from the hypotonic environment via osmosis and use bladder-like contractile vacuoles to accumulate excess water from radial canals and periodically expel it through the plasma membrane by contractions of the surrounding cytoplasm.[3] The contractile vacuoles also serve to maintain osmotic pressure.[2] When moving through the water, they follow a spiral path while rotating on the long axis.[2]
Paramecium have two nuclei (a large macronucleus and a single compact micronucleus).[4] They cannot survive without the macronucleus and cannot reproduce without the micro-nucleus[3]. Reproduction is either accomplished by binary fission (asexual), conjugation (sexual)[3], or (rarely) by endomixis, a process involving total nuclear reorganization of individual organisms.[2] During binary fission a fully grown organism divides into two daughter cells.[3] Conjugation consists of the temporary union of 2 organisms and the exchange of micro-nuclear elements[3]. Without the rejuvenating effects of conjugation a paramecium ages and dies.[3] Only opposite mating types, or genetically compatible organisms, can unite in conjugation.[3]
Paramecium caudatum can communicate with neighbors using a non-molecular method, probably photons.[5] The cell populations were separated either with glass allowing photon transmission from 340 nm to longer waves, or quartz being transmittable from 150 nm, i.e. from UVlight to longer waves. Energy uptake, cell division rate and growth correlation were influenced. [6]Like paramecium bursaria, when caudatum is added to synthetic fertilizer, they die.