Question

Cilia and flagella are outgrowths of
A. Cell wall
B. Nucleus
C. None of these
D. Both of them

Answer 1

Hint: Cilia and Flagella are fine and Filamentous hair-like structures, The main function of cilia and Flagella is to move the cell or the substance present around the cell.

Complete Answer:
Cilia and Flagella are Filamentous Extensions which project outwards from the cell wall, Cilia and flagella are made up of microtubules and are covered by the plasma membrane and the internal structure of both cilia and flagella are similar. The coordination between the microtubules in cilia and Flagella is very important for their movement.

- Option(A): Cilia and Flagella are extensions of the cell wall Therefore, this is the Correct option.
- Option(B): Cilia and Flagella are not extended from the nucleus and Therefore, this is an Incorrect option.
- Option(C): Since one of the options is correct, Therefore this is an Incorrect option.
- Option(D): Since only one option is correct from the two options and not both of them are correct, Therefore this is an Incorrect option.

Hence the correct answer is option A.

Additional Information:
- Microtubules are arranged radially as nine pairs of doublets which form the core of cilia and flagella which are also known as peripheral microtubules and it is known as Axoneme.
- There is also a pair of central microtubules which are connected by bridges and covered by a central sheath and is connected to the radial doublets with a radial spoke.

Note: - The structure of prokaryotic flagella and Eukaryotic flagella are different.
- Cilia are small structures whereas flagella are comparatively longer.
- Cilia and flagella arise from centriole-like structures which are known as Basal bodies.