portrait, bell

Description:

Vorticella (vort-ee-sell-a) the iconic peritrich ciliate. The feeding cells in sessile peritrich ciliates have lost all of the somatic cilia and only have the feeding cilia. The feeding cilia form a wreath which extends around the front of the cell and descends into a narrowing buccal cavity. This cavity ends at the cytostome where food is packaged into food vacuoles and can be seen at the top of this cell, as can many food vacuoles. If the cells become unhappy, they produce a temporary wreath of basal cilia (trochal cilia), break away from their stalk and use these to swim. This cell has the trochal cilia. Daughter cells are produced near the base of the parental cells and have the trochal cilia so that they can swim around when they break from at the end of division. Most peritrichs have a large curving macronucleus, and this is also evident towards the top of the cell. The stalk, not evident here, contains a contractile filament, and when this contracts it coils up a bit like a spring. Differential interference contrast.