Microtubules are the constituents of:
Answer: (B) Spindle fibres, centrioles and cilia. Answer: (B) Spindle fibres, centrioles and cilia Solution: Microtubules are the building units of all three of these structures.
- A.Cilia, Flagella and Peroxisomes
- B.Spindle fibres, centrioles and cilia✓
- C.Centrioles, spindle fibres and chromatin
- D.Centrosome, Nucleosome and Centrioles
Correct Answer
(B) Spindle fibres, centrioles and cilia
Solution & Explanation
Answer: (B) Spindle fibres, centrioles and cilia Solution: Microtubules are the building units of all three of these structures. Centrioles are made of nine peripheral triplets of tubulin protein, and they give rise to the spindle fibres during cell division. The core (axoneme) of a cilium also possesses microtubules in the 9+2 array. Peroxisomes, chromatin, nucleosomes and the centrosome are not built of microtubules, so the other options are wrong. NCERT Reference: Ch 8, p.100, lines 3-9: "made up of nine evenly spaced peripheral fibrils of tubulin protein... The centrioles form the basal body of cilia or flagella, and spindle fibres that give rise to spindle apparatus during cell division in animal cells."