Which of the following is an example of a sesamoid bone?

Choice A reason: While muscle names can reflect location (e.g., brachialis for the arm), the names "biceps," "triceps," and "quadriceps" specifically refer to the number of origins, not their anatomical position.

Choice B reason: "Biceps" means two heads, "triceps" means three heads, and "quadriceps" means four heads. These names are derived from the number of tendinous origins each muscle has, making this the correct classification.

Choice C reason: Muscle shape does influence naming in some cases (e.g., deltoid for triangular), but it is not the basis for naming biceps, triceps, or quadriceps.

Choice D reason: Fascicle arrangement refers to the pattern of muscle fibers (e.g., parallel, pennate), which affects function and strength but is not the naming basis for these specific muscles.

Choice A reason: Perforating canals (also known as Volkmann's canals) connect the central canals of different osteons and allow blood vessels and nerves to travel across bone. While they contribute to nutrient transport, they do not directly facilitate exchange between osteocytes.

Choice B reason: Lamellae are concentric rings of bone matrix within osteons. They provide structural support but do not directly mediate nutrient or waste exchange between osteocytes.

Choice C reason: Central canals (Haversian canals) contain blood vessels and nerves and run longitudinally through osteons. They help deliver nutrients to the bone but do not directly connect individual osteocytes.

Choice D reason: Canaliculi are microscopic channels that connect osteocytes within lacunae to each other and to the central canal. These channels allow for the direct exchange of nutrients and waste products between osteocytes, making them the most direct structure for this function.