Question

Arrangement of microtubules in a flagellum and a centriole is respectively _________
A. 9$ + $2 and 9$ + $1
B. 9$ + $1 and 0$ + $0
C. 9$ + $0 and 9$ + $2
D. 9$ + $2 and 9$ + $0

Answer 1

Hint:-Microtubules are polymers of tubulin that are a part of the endoskeleton and also provide structure and shape to the eukaryotic cell. The flagellum is a slender thread-like structure that is microscopic in nature.

Complete answer:-
Microtubules are hollow cylinders that are made up of repeating protein structures alpha and beta tubulins. The alpha and beta tubulins join together to form dimers. They are polar molecules with positively charged ends that grow faster and negatively charged ends that grow slowly. In animal cells, they form the centrosome. The main function of microtubules includes cell movement where they become part of the cilia or flagella. They form the mitotic spindle during the cell division.
The flagellum is the primary organelle that is used for locomotion. It is the characteristic of protozoan groups. Centriole consists of a small set of microtubules that are arranged in a specific way. There are nine groups of microtubules. Centrioles are involved in the organization of the mitotic spindle and the process of cytokinesis. A centrioles microtubule is arranged in whorls of 9 where it is absent in the centre. Hence it is 9$ + $0 in the case of the centriole. In the case of the flagellum, the 9 microtubules are present at the periphery and two are present at the centre.
The correct answer is option (D), 9$ + $2 and 9$ + $0.

Note:- The bacteria that have the presence of flagellum will move by whipping movement of bacteria. The bacteria beat the flagellum in such a way that it creates a wave that passes from base to tip of the flagellum that creates backwards and forward movement.