The metacarpal bones are part of which skeletal division?

Correct Answer: B

Rationale: The metacarpal bones, found in the hand, are part of the appendicular skeleton, which includes the limbs and girdles. They are long bones but belong to the appendicular division, not axial (skull, spine, ribs). 'Long bones' is a type, not a division, making 'Appendicular skeleton' correct.

Correct Answer: B

Rationale: At the neuromuscular junction, the motor neuron releases acetylcholine into the synaptic cleft, stimulating the muscle fiber to contract. Calcium is stored in the sarcoplasmic reticulum, ATP is produced in mitochondria, and muscle fibers contract, not neurons, making 'Release acetylcholine' correct.

Correct Answer: A

Rationale: A joint, or articulation, is the anatomical location where two bones connect, allowing for stability or movement (e.g., knee, shoulder). Tendons connect muscles to bones, ligaments connect bones to other bones, and muscles move bones but aren’t the meeting point, making 'joint' the correct answer.

Correct Answer: D

Rationale: Short bones, like carpals and tarsals, have roughly equal length and width, providing stability and support. Flat bones are thin and broad, irregular bones have complex shapes, and long bones are longer than wide, making 'short' the correct classification.

Correct Answer: D

Rationale: Compact bone is organized into cylinder-shaped units called osteons (or Haversian systems—both terms are synonymous), containing lamellae and a central canal. Trabeculae are in spongy bone, not compact, so 'Both A and C are correct' reflects the interchangeable terminology.