Biological Systems MCAT Practice Exam

What type of cartilage is found in intervertebral disks and is known for its rigidity?

1. Elastic cartilage

2. Fibrous cartilage

3. Hyaline cartilage

4. Articular cartilage

The correct answer is: Fibrous cartilage

The type of cartilage found in intervertebral disks is fibrous cartilage, which is known for its rigidity and strength. Fibrous cartilage is characterized by a dense network of collagen fibers, making it particularly suitable for structures that require both support and the ability to withstand compressive forces. This type of cartilage provides shock absorption and helps maintain the integrity of the spinal column during movement, enabling the vertebrae to absorb impacts and reduce strain. In contrast, elastic cartilage, while flexible and present in structures like the ear and epiglottis, does not have the same mechanical strength needed for intervertebral disks. Hyaline cartilage, which is found in places such as the ends of long bones and the ribs, is more resilient but lacks the dense collagen fiber composition of fibrous cartilage. Lastly, articular cartilage, which covers the surfaces of bones at joints, is designed to facilitate smooth movements rather than provide the same level of rigidity as fibrous cartilage in the spinal disks. Thus, fibrous cartilage is the appropriate answer when considering the specific properties needed for intervertebral disks.