Ribs are flat bones. Do they get longer or shorter going from 8 to 12?

Correct Answer: B

Rationale: Ribs decrease in length from 8 to 12 as they curve around the chest; rib 8 is longer, while ribs 11 and 12 (floating) are shortest, reflecting their reduced role in enclosing the thorax.

Correct Answer: A

Rationale: Yes, an interosseous membrane connects the tibia and fibula along their lengths, similar to the forearm, providing stability and a surface for muscle attachment.

Correct Answer: C

Rationale: The shoulder joint (glenohumeral joint) is a ball-and-socket joint, where the humerus’s rounded head fits into the scapula’s glenoid cavity, allowing a wide range of motion (e.g., rotation, abduction). Hinge joints (e.g., elbow) allow one-plane movement, pivot joints (e.g., atlas-axis) rotate, and saddle joints (e.g., thumb) have a different articulation.

Correct Answer: B

Rationale: Long bones (e.g., femur, humerus) have a hollow shaft (diaphysis) and expanded ends (epiphyses), designed for weight-bearing and movement in the limbs. Flat bones (e.g., sternum) are thin, short bones (e.g., carpals) are cuboidal, and irregular bones (e.g., vertebrae) have complex shapes.