Which of the following are involved in the beating of the cilia and flagella:
These are non-membraneous cell organelles which are the polymers of tubulin. They are the one of the constituents of the cytoskeleton and are also involved in the subcellular movements. Microtubules are found in:
1. Axoneme of cilia and flagella
2. Basal bodies of cilia
3. Mitotic spindle fibers
Structure of Microtubules:
They are elongated polymeric structures that are made up of equal parts of alpha-tubulin and beta-tubulin. Theses are hollow non-branching cylinders that measure 20-25 um. The wall of the microtubules consists of 13 circularly arranged globular proteins called protofilaments. Each alpha and beta-tubulin has a molecular weight of 55,000. These alpha and beta-tubulin dimers bound to each other in a repeating fashion forming protofilaments.
Functions of Microtubules:
1. They are involved in cell elongation and movement that is migration.
2. Aid in intracellular transport of secretory granules.
3. Movement of chromosomes during mitosis and meiosis.
4. Regulate cell shape.
5. Essential for the beating of cilia and flagella.