Question

Which of the following is not an ear ossicle?
A. Incus
B. Malleus
C. Humerus
D. Stapes

Answer 1

Hint: The ossicles are three bones in either middle ear that are among the smallest bones in the human body.
-They serve to transmit sounds from the air to the fluid-filled cochlea.

Complete step by step answer:
-Humerus bone is not an ear ossicle. Ear ossicles consist of the malleus, incus and stapes.
-It is a long bone in the arm or forelimb that runs from the shoulder to the elbow.
The humerus connects the scapula and the two bones of the lower arm, which consists of the radius and ulna.
-Incus bone is an anvil shaped ear ossicle. It is so called because of its resemblance to anvil. It is the second bone out of three bones found in the middle ear.
-Malleus has a long limb and a short limb that protrude from the point of articulation with the malleus.
-Malleus conveys vibrations to the incus which in turn conveys vibrations to the stapes.
The stapes is a stirrup shaped bone found in the middle ear for the conduction of sound vibration to the middle ear. It rests on the oval window, to which it is connected by an annular ligament.

Hence the correct option is C.

Note:
Ear ossicles consist of three tiniest bones in the body form the coupling between the vibration of the eardrum and the forces exerted on the oval window of the inner ear.
The bones are malleus, incus, and stapes; they are commonly referred to as the hammer, anvil, and stirrup.