Question

What is a microtubule?

Answer 1

Ans:

When and tubulins, the two dimers of globular proteins, polymerize into protofilaments, a hollow tube is formed called the microtubules.The structure and shape of the cytoskeleton is given by these polymers of tubulin called microtubules.They are highly dynamic and grow very long which can go upto 50micron.Microtubules emerges from microtubule organizing centers and are nucleated in nature.Microtubles have binding affinity to proteins like motor proteins kinesin and dynein, that plays a major role in vesicle trafficking and also in cell division.

These microtubules play vital roles in various cellular processes and cell divison processes like meiosis and mitosis.Some of their other functions/roles are:

• They form the cytoskeletion together with intermediated and micro filaments.
• Internal structure of cilia and flagella is also made up of microtubules.
• They provide medium for intracellular transport and also helps in the movement of organelles and secretory vesicles.
• In mitosis, the spindles responsible for pulling the chromosomes apart is also made up of microtubules.