Question

What motor protein is involved in the flagellum and what does it cause?

1) Myosin, it causes contraction
2) Kinesin, it causes movement
3) Dynein, it causes bending
4) Actin, it causes extension

Answer 1

The motor protein involved in the flagellum is dynein, which causes the flagellum to bend and facilitates the movement of cells or fluids by generating whipping or beating actions characteristic of cilia and flagella.

Step-by-step explanation:

The motor protein involved in the flagellum is dynein, which causes the flagellum to bend.

Dynein, along with another motor protein called kinesin, is known to interact with microtubules, which are structural components of flagella and cilia. Dynein arms are attached to the A tubules of outer doublets in the 9+2 axoneme structure of cilia and flagella.

The dynein motor proteins 'walk' along adjacent B tubules, creating a sliding mechanism that, due to the constraints by the flexible nexin and radial spoke attachments, results in bending. This action, powered by the hydrolysis of ATP, generates the whipping or beating motions characteristic of cilia and flagella, enabling cell motility and the movement of fluids across cell surfaces.