American Academy of Professional Coders (AAPC) Practice Exam

What primarily makes up cartilage?

1. A matrix of chondrocytes, collagen, and proteoglycans

2. An outer layer of bone and synovial fluid

3. Adipose tissue and blood vessels

4. Nerve fibers and muscle fibers

The correct answer is: A matrix of chondrocytes, collagen, and proteoglycans

The primary composition of cartilage consists of a matrix that includes chondrocytes, collagen, and proteoglycans. This unique structure serves several crucial functions in the body. Chondrocytes are the specialized cells found in cartilage, responsible for producing and maintaining the cartilaginous matrix. This matrix provides the essential support and resilience that cartilage is known for. Collagen fibers contribute strength and stability, while proteoglycans promote hydration and help to create the gel-like consistency that is characteristic of cartilage. This combination allows cartilage to withstand compression and provide cushioning in joints, which is vital for overall joint health and mobility. The other options, while they describe various tissues or structures, do not accurately reflect the makeup of cartilage. The mention of an outer layer of bone and synovial fluid pertains to joint structures rather than directly to cartilage itself. Adipose tissue and blood vessels are components of other types of tissue, predominantly involved in energy storage and circulation, rather than cartilage. Lastly, nerve fibers and muscle fibers are associated with nervous and muscular systems, not with the structural framework of cartilage. Thus, the correct answer reflects the fundamental components that define cartilage's structure and function.