What type of bone is described as porous and spongy?

• A. Cortical bone
• B. Trabecular bone
• C. Fibrous bone
• D. Compact bone

Answer: (B)

The type of bone described as porous and spongy is trabecular bone. This bone tissue, also known as cancellous bone, is characterized by a lattice-like structure filled with bone marrow and is found at the ends of long bones, within the vertebrae, and in the interior of other bones. The porous nature of trabecular bone allows for flexibility and lightness while providing structural support and housing for red and yellow bone marrow.

Trabecular bone is crucial for the overall function of the skeletal system, playing a significant role in shock absorption and load distribution. Its high surface area-to-volume ratio allows for efficient metabolic activity and mineral exchange. Bone density tests often focus on assessing trabecular bone density since it is more susceptible to changes due to conditions such as osteoporosis.

In contrast, cortical bone refers to the dense outer surface of bone that is smooth and strong but not porous. Fibrous bone is a type of connective tissue and does not classify as one of the main bone types involved in mineral storage or skeletal structure. Compact bone is another term for cortical bone and does not exhibit the porosity characteristic of trabecular bone. Thus, trabecular bone is the correct answer when identifying the type of bone that is porous and