Question

Axoneme is a structure associated with
A. Golgi bodies
B. Only cilia
C. Only flagella
D. Both cilia and flagella

Answer 1

Microtubules are the thickest filaments of the cytoskeleton. They are the structural components of the extensions of the plasma membrane involved in cell movements. The central core of these mobile cellular appendages is made of up microtubule doublets.

Complete answer:
Cells are the structural and functional units of life. The Golgi bodies are one of the various membrane-bound organelles present in the eukaryotic cells. Golgi bodies are composed of stacks of flat membranous sacs called cisternae. They serve as the site for modification, packaging, and sorting of the substances (mainly proteins and lipids) formed on the endoplasmic reticulum.

The axoneme is the structure derived from microtubules. Microtubules are one of the three different types of protein polymers that make the cytoskeleton. These protein polymers are actin filaments, intermediate filaments, and microtubules. Microtubules are the polymers of the tubulin proteins and are involved in the movement of cells and cellular structures such as chromosomes.

Cilia and flagella are the extensions of the plasma membrane present on the surface of prokaryotes and some epithelial cells of eukaryotes. The basic structure of cilia and flagella is the same. These are the membrane-bound cylindrical structures. The matrix of cilia and flagella consists of the axoneme. The axoneme is composed of nine pairs of microtubule doublets arranged circularly at the periphery with two central tubules.

Hence, the correct answer is option (D).

Note: The arrangement of microtubules in axoneme is called the 9+2 pattern. The microtubule doublets of the axoneme of cilia and flagella slide along one another to move these structures. Therefore, the axoneme represents the mobile core of cilia and flagella.