Question

Write the mechanism of bending of flagellum and explain effective and recovery strokes.

Answer 1

A ciliary beat has two distinct phases – power stoke (or effective stroke) and recovery stroke (or return stroke). During power stroke

Answer 2

Mechanism of bending of flagellum:

• Flagella and cilia are the locomotory organs of bacteria.

• It works on the whip-lash mechanism, which helps move the bacteria forward. The flagellum is attached to the cell surface through hook.

• The flagellum moves clockwise and anti-clockwise which can also be a propeller motion.

Effective stroke

• The cilia bend towards one side, making an "oar-like movement" which is called the effective stroke.

Recovery stroke

• The reverse mechanism is called recovery mechanism and involves recovery strokes.