Question

The usual axonemal arrangement of microtubules is

• A. 6 pairs of doublets radially arranged at the periphery with a single centrally located microtubule
• B. 6 pairs of doublets radially arranged at the periphery with a pair of centrally located microtubules
• C. 9 pairs of doublets radially arranged at the periphery with a pair of centrally located microtubules
• D. 9 pairs of doublets radially arranged at the periphery with a single centrally located microtubule

Answer 1

The correct option is C

9 pairs of doublets radially arranged at the periphery with a pair of centrally located microtubules

The flagella are enclosed by a plasma membrane. Within the membrane is a core called axoneme. The axoneme has 9 pairs of doublets of microtubules radially arranged at the periphery and a pair of centrally located microtubules.