Question

What are the components of the cytoskeleton?

Answer 1

Cytoskeleton:

1. It helps the cells to maintain shape and internal organization and also provides mechanical support.
2. It enables the cell to carry out functions like division and movement.
3. There are three components of cytoskeletal components- microtubules, microfilaments, and intermediary filaments.

Microtubules:

1. They are 25 nm in diameter with a lumen of 15 nm in diameter.
2. They give structural and mechanical support to the cell.
3. They help in the locomotion of cilia and flagella.
4. They help in the formation of the mitotic spindle during cell division.
5. They help in determining cell polarity and play a vital role in cell differentiation.

Microfilaments:

1. It is a long thin cylindrical structure of diameter ranging from 6-10 nm.
2. It is composed of actin and myosin proteins which are essential for the contraction of microfilaments.
3. It is a helical polymer of dumb-bell-shaped subunits.
4. The subunits are monomeric in nature.
5. Their main function is to support the fluid matrix.
6. They help in the movement of myofibrils of muscle fibers.
7. In microvilli, they help in the rapid absorption of food.
8. They help in the movement of cell organelles.
9. They cause muscle contraction.

Intermediary filaments:

1. They are hollow and noncontractile filaments.
2. They are 10nm in thickness which forms a network.
3. They are composed of structural proteins like keratin, vimentin, and desmin.
4. Their primary function is to maintain the cell shape.
5. They also keep the organelles in position and support the myofibrils.
6. They also form a scaffold for chromatin of the nucleus.