Question

multiple choice 2 points

the bones below belong to the axial skeleton, except the ________, which belongs to the

stapes
thoracic vertebra
frontal bone
scapula
mandible

Explanation:

Define the axial and appendicular skeleton

The human skeleton is divided into two main parts: the axial skeleton and the appendicular skeleton. The axial skeleton forms the central axis of the body and includes the skull, vertebral column, ribs, sternum, and auditory ossicles. The appendicular skeleton consists of the limbs and the girdles (pectoral and pelvic) that attach the limbs to the axial skeleton.

Analyze each option

• stapes: An auditory ossicle located in the middle ear, which is part of the axial skeleton.
• thoracic vertebra: Part of the vertebral column, which is part of the axial skeleton.
• frontal bone: A bone of the skull, which is part of the axial skeleton.
• scapula: The shoulder blade, which is part of the pectoral girdle. This belongs to the appendicular skeleton.
• mandible: The lower jawbone, which is part of the skull (axial skeleton).

Identify the exception

The question asks for the bone that does not belong to the axial skeleton ("except the..."). Since the scapula belongs to the appendicular skeleton, it is the correct exception.

Answer:

• stapes
• thoracic vertebra
• frontal bone
• scapula (Correct answer)
• mandible