Which one of the following is the primary function of sesamoid bones?

Correct Answer: A

Rationale: Sesamoid bones (e.g., patella) are embedded in tendons, absorbing impact and protecting tendons during flexion (e.g., knee movement). B, C, and D apply to other bone types, making 'Absorb impact forces and protect tendons as they flex' correct.

Correct Answer: A

Rationale: A trochanter is a bony projection on the femur—greater (lateral) and lesser (medial)—for muscle attachment, not articulation or a groove. It’s specific to the femur, not pelvis. Answer is A, per the document.

Correct Answer: C

Rationale: The mandible’s temporomandibular joint (with the temporal bone) is synovial, allowing chewing/speaking. Sphenoid, maxilla, and hyoid lack synovial joints (sutures or none). Answer is C, per the document.

Correct Answer: B

Rationale: Appendicular skeleton includes limbs/girdles: clavicle, fibula, metatarsal, phalange, radius are all appendicular. Ethmoid, coccyx, occipital, sternum, mandible are axial. Answer is B, per the document.

Correct Answer: C

Rationale: A trabeculum (trabeculae) is an internal structure in spongy bone, not a surface projection. Trochanter, tubercle, and tuberosity are projections. Answer is C, per the document.