Question

Which of the following bones is responsible for side-to-side movement of the head?

a. Axis
b. Lamellae
c. Atlas
d. Sacrum

Answer 1

The axis (C2 vertebra) is the bone responsible for side-to-side movement of the head, enabling rotation as seen when shaking the head 'no'.

Step-by-step explanation:

The bone responsible for the side-to-side movement of the head is the axis (b). The axis is the second cervical (C2) vertebra and serves as the pivot for rotation when turning the head to the right or left.

This movement is made possible through the atlantoaxial joint between the atlas (C1) and the axis (C2), with a key feature being the dens (odontoid process), which allows the atlas to rotate atop the axis.