Which of these statements about articular cartilage are false? Is slippery due to high amounts of hyaluronic acid Is not covered with perichondrium is made of fibrocartilage Covers the epiphyses
The Correct Answer and Explanation is:
Based on the options provided, the correct answer is that the statement “is made of fibrocartilage” is false.
Explanation:
The statement claiming that articular cartilage is made of fibrocartilage is incorrect. Articular cartilage is a highly specialized form of hyaline cartilage. This distinction is crucial to understanding its function within synovial joints.
Hyaline cartilage, the type that constitutes articular cartilage, is characterized by a smooth, glassy appearance. Its extracellular matrix is primarily composed of type II collagen fibers, water, and proteoglycans like aggrecan. This composition gives it a firm, rubbery consistency, making it perfectly suited to provide a low friction surface for joint movement and to absorb shock and compressive forces. It lines the ends of bones, specifically the epiphyses, within a joint capsule.
In contrast, fibrocartilage is a different type of cartilage altogether. It is a mixture of hyaline cartilage and dense fibrous connective tissue, containing a significant amount of tough type I collagen fibers in addition to type II. This makes fibrocartilage much stronger and more resistant to tearing and stretching. It is found in areas that must withstand immense pressure and tension, such as the intervertebral discs, the pubic symphysis, and the menisci of the knee. Its structure is not designed for the smooth gliding motion required in most articular surfaces.
The other statements about articular cartilage are true. It does cover the epiphyses (the ends) of long bones. It is not covered with perichondrium, a layer of connective tissue that covers most other cartilage. This lack of perichondrium means it has no direct blood supply and has a very limited capacity for self repair. Finally, within the joint, the surface of articular cartilage is slippery, a property greatly enhanced by the synovial fluid that bathes it. This fluid is rich in hyaluronic acid and lubricin, which work together to create an almost frictionless environment for smooth joint articulation
