Identify the bone cell that is derived from the type of white blood cell called monocytes.

Correct Answer: D

Rationale: Osteoclasts, which break down bone, derive from monocytes (white blood cells) in the bone marrow. Osteoprogenitor cells are stem cells, osteoblasts form bone, and osteocytes maintain it, making 'osteoclasts' the correct answer.

Correct Answer: A

Rationale: Cranial bones form the cranium: frontal, parietal, occipital, temporal, sphenoid, and ethmoid. The ethmoid is cranial, while nasal, vomer, and zygomatic are facial bones, making 'ethmoid' correct.

Correct Answer: B

Rationale: The maxillae form the upper jaw, supporting upper teeth and part of the palate. The mandible is the lower jaw, vomer the nasal septum, and zygomatic the cheeks, making 'maxillae' correct.

Correct Answer: A

Rationale: The sacrum in adults is 5 vertebrae fused into one bone, supporting the pelvis. The total spine has 33 vertebrae, but only 5 form the sacrum, making '5' correct.

Correct Answer: D

Rationale: The sternum has three parts, from superior to inferior: manubrium (top, rib 1-2 attachment), body (middle, rib 3-7 attachment), and xiphoid process (bottom). 'manubrium, body and xiphoid process' is the correct order.