Question

The filaments present in cilia or flagella are

• A. microvilli
• B. microfibrils
• C. microfilaments
• D. microtubules

Answer 1

The correct option is D microtubules

The cilia and flagella are locomotory structures commonly found as extensions of the plasma membrane in prokaryotes. They are anatomically made up of microtubules which are arranged in a 9 + 2 pattern. Their core, called the axoneme, possesses a number of microtubules running parallel to the long axis.
The axoneme usually has nine doublets of radially arranged peripheral microtubules, and a pair of centrally located microtubules.

Microfibrils are small fibrils (thin thread-like structures) found in the cytoplasm. They are normally made up of glycoproteins and proteins.

The cytoskeleton which supports the cell is made up of microtubules, microfilaments and intermediate filaments which are proteinaceous in nature.

Microtubules are small tube-like structures made up of tubulin proteins and are also found in the cytoskeleton providing support to the cell organelles.

Microvilli are small finger-like projections found in some cells which help in increasing the surface area of absorption.