A flattened or shallow articulating surface of a bone is called a

Correct Answer: D

Rationale: A facet is a flat or shallow surface on a bone where articulation occurs, such as in vertebral joints. A tubercle is a small projection, a fossa is a depression, and a fovea is a small pit—none describe a shallow articulating surface as precisely as facet.

Correct Answer: C

Rationale: The tibia, a long bone, has a diaphysis (shaft), epiphyses (ends), articular cartilage (at joints), and a medullary cavity (marrow space). Scapula and sacrum are flat/irregular bones, and the patella (sesamoid) lacks a medullary cavity.

Correct Answer: C

Rationale: The talus, in the ankle, articulates distally with the calcaneus (heel bone) below it, forming the subtalar joint. The navicular and cuneiforms are more distal, and the first metatarsal is further forward.

Correct Answer: B

Rationale: Bone marrow consists of adipose tissue (yellow marrow, fat storage), areolar tissue (loose connective tissue supporting structure), and blood (red marrow, site of hematopoiesis producing blood cells). Fibroblasts are present but not a major component, making B the most complete and accurate description.

Correct Answer: A

Rationale: Haversian canals are channels in compact bone containing blood vessels and nerves, characteristic of long bones like the humerus. Scapula (flat), pubis (irregular), and clavicle (long but less typical) have compact bone, but the humerus is a classic example of Haversian system structure.