Ques. 1AIPMT 2001
Microtubules are absent in:
- Spindle fibres
- Mitochondria
- Centriole
- Flagella
Answer
(2) Mitochondria
Solution
As per NCERT, the axoneme of cilia and flagella has nine pairs of peripheral and two central microtubules (9 + 2 array).
∵ Each centriole has nine evenly spaced peripheral fibrils of tubulin triplets, and centrioles form the basal bodies and the spindle fibres (made of microtubules) of the spindle apparatus.
⇒ Mitochondria are double-membrane-bound organelles with matrix and cristae; they have no microtubules.
Answer: (2)