Paramecium is a ciliate protozoan. Ciliates’ bodies are covered
with fine cytoplasmic hair-like structures called cilia.
Flickering movements of the cilia propel the organism through
the water and also create feeding currents. Paramecium is a
ciliate. In describing its structure, comparisons will be made
with amoeba. It is suggested, therefore, that amoeba is studied
first. Unlike amoeba, paramecium has a distinct and permanent
shape and certain areas of cytoplasm, (cell organelles), are
specialised to carry out specific functions. Locomotion.
Individual cilia bend and straighten rapidly in such a way that
the recovery stroke offers minimal resistance and the bending
stroke helps propel paramecium through the water. The whole
complement of cilia beat in a rhythmic pattern, (metachronal
rhythm), so that the waves of contraction pass over the cell
body like wind blowing through ripe corn. If paramecium
encounters an obstacle, it reverses the ciliary beat and moves
back. It then changes direction slightly and mo