Question

What are the similarities and differences between the structures of centrioles and flagella?

Short answer

Centrioles and flagella are both composed of microtubules but differ in the arrangement of microtubules.

Step-by-step solution

Introduction

Flagella are hair-like structures that protrude from the plasma membrane and aid in the movement of a cell. Centrioles are located in the cytoplasm of a cell and play a role in cell division.

Explanation

The similarity between centrioles and flagella is that both are made up of microtubules.

Centrioles differ from flagella in the arrangement of the microtubules. Centrioles are hollow cylindrical tube-like structures composed of 9 microtubule triplets arranged in a ring-like fashion. The microtubule triplets are parallel to each other but at an angle of 40⁰. Microtubules are absent in the central core; therefore, it has a 9+0 arrangement. The pair of centrioles are arranged at right angles to each other.

On the other hand, flagella have 9 pairs of microtubules fused and arranged in a ring-like fashion with a single pair of unfused microtubules in the center. This type of arrangement is known as a 9+2 pattern.