Question

The main function of microtubules is
A. Protein synthesis
B. Movement of cilia and flagella
C. Formation of spindle fibres
D. Both (B) and (C)

Answer 1

Hint: The microtubules are hollow cylinders that are made up of tubulin proteins and they are part of the cell’s cytoskeleton. They have their role in cell movement, cell division, and transporting materials within the cells.

Complete answer:
> Option (A) is incorrect. Protein synthesis involves the synthesis of proteins by the ribosomes from the mRNA that has been transcribed from the DNA in the nucleus. During translation, mRNA is decoded into amino acids outside the nucleus to produce an amino acid chain which further folds into an active protein. Microtubules have no role in the process of protein synthesis.

> Option (B) is correct. Cilia and flagella are composed of microtubules. Both cilia and flagella have arrangements of microtubules. Both these structures help in the locomotion of either the cell or the substances present around the cell. Since cilia and flagella are made up of microtubules therefore their movement is aided by the microtubules.

> Option (C) is correct. Spindle fibres help in the division of genetic material during the cell division. They are the fibres that are formed from microtubules, extended from the centriole in all possible directions to equally divide the genetic material.

> Option (D) is correct. Microtubules are known for aiding the movement of cilia and flagella as well as in the formation of spindle fibres. Therefore, both the options (B) and (C) are correct.

Hence, the correct answer is option (D).

Note: Microtubules are nucleated and are known for maintaining the structure of the eukaryotic cells, making the structure of the cilia and the flagella, aiding the movement of secretory vesicles, organelles. They are also the constituents of spindle fibres.