Question

Flagella are composed of

• A. $9$ pairs of microtubules surrounding a central pair of microtubules
• B. $9$ pairs of microtubules surrounding a single central microtubule
• C. $9$ microtubules surrounding a central pair of microtubules
• D. None of these

Answer 1

The correct option is A $9$ pairs of microtubules surrounding a central pair of microtubules

Flagella and cilia consist of 9 fused pairs of protein microtubules with side arms of the motor molecule dynein that originate from a centriole. These form a ring around an inner central pair of microtubules that arise from a plate near the cell surface. The arrangement of microtubules is known as a 2X9+2 arrangement.

Hence the correct answer is (A)