National Dental Assisting Examining Board (NDAEB) Practice Exam

Which term refers to the spicules in cancellous bone forming a meshwork within the marrow?

1. Alveoli

2. Trabeculae

3. Osteocytes

4. Cortex

The correct answer is: Trabeculae

The term that refers to the spicules in cancellous bone forming a meshwork within the marrow is "trabeculae." Trabeculae are the small, rod-like structures that create a network within the spongy (cancellous) bone, providing support and strength while also helping to lighten the bone structure. This network of trabeculae allows for the accommodation of bone marrow and provides sites for blood cell production. In contrast, alveoli refer to the small air sacs in the lungs where gas exchange occurs and are not associated with bone. Osteocytes are mature bone cells that maintain the bone matrix but do not refer to the structure in question. The cortex refers to the outer layer of bone, particularly in compact bone, and does not involve the spicules of cancellous bone. Thus, trabeculae is the appropriate term for the meshwork structure within the marrow of cancellous bone.