Paramecium cell

See Paramecium

According Beale; ‘one hypothesis suggests that Paramecium has been round even before the continents separated and has not moved; only continents have’. That is why the ciliated protozoa is readily found all over the world living in fresh water and feed on microscopic organisms such as bacteria and single-celled algae and move by propelling their cilia, back and forth in prompted quick succession (Beale & Preer., 2008: 16).

As one of the oldest primitive organisms on earth, Paramecia are among the first organisms used to clarify the Universal genetic code. It is still of much historical interest to geneticists, today, known to use a variant genetic code (UAA and UAG = Glu not stop). (Hames & Hooper, 2011: 252).

Like most other single celled organism, they divide by binary fission. Occasionally, Paramecia exchange genetic material in a kind of primitive sexual reproduction using a parole cone like protuberance which passes gamete nuclei from one conjugate to another (Beale & Preer 2008; 26).

A peculiar behavioral response is demonstrated by Paramecia; when exposed to any physical or chemical stimuli they propel faster or discharge a spine-like structure from their outer coating called trichocyst at the stimulus as a protective defense measure against being pursued or devoured by predators (Beale & Preer 2008; 26).

Studying Paramecium cell has produced concepts that are widely accepted to advance knowledge leading to a better understanding of mechanisms like the muscle sliding filament phenomenon and the evolution of the neuronal functions of higher organisms.

References:

Beale, G.H. and Preer, J. R. (2008). Paramecium Genetics and Epigenetics, e-book, accessed 26 November 2012 from http://www.ncl.ac.uk/library/e-books.

Hames, D. and Hooper, N. (2011) BIOS Instant notes: Biochemistry, 4th edition, New York: Garland Science.