What best describes the structure of a synovial joint?
Cartilage is situated between the articulating bones.
The joint is fastened together by dense regular collagenous connective tissue.
No joint space separates the articulating bones.
A fluid-filled cavity is found between the articulating bones.
The correct answer and explanation is :
The correct answer is:
A fluid-filled cavity is found between the articulating bones.
Explanation:
Synovial joints are the most common and movable type of joints in the human body. They are characterized by the presence of a synovial cavity, which is a fluid-filled space between the articulating bones. This unique feature distinguishes synovial joints from other types of joints, such as fibrous or cartilaginous joints, which do not have a synovial cavity.
The structure of a synovial joint is quite complex and includes several key components that facilitate movement while ensuring stability and protection:
- Articular Cartilage: The ends of the articulating bones are covered with smooth, hyaline cartilage. This cartilage reduces friction and absorbs shock during movement, providing smooth gliding motion at the joint.
- Synovial Cavity: The defining feature of synovial joints is the synovial cavity, a space between the articulating bones. This cavity is filled with synovial fluid, a viscous substance that lubricates the joint, reducing friction, nourishing the cartilage, and removing metabolic waste.
- Synovial Fluid: Synovial fluid is produced by the synovial membrane that lines the inner surface of the joint capsule. This fluid plays a critical role in lubrication and nourishment, which is essential for the health and function of the joint.
- Joint Capsule: The joint capsule is a double-layered structure. The outer layer is made of dense fibrous connective tissue, which provides stability and helps hold the bones together. The inner layer, known as the synovial membrane, secretes synovial fluid.
- Ligaments: Ligaments are dense bands of fibrous tissue that connect the bones and provide additional stability to the joint.
Overall, the combination of the synovial cavity, synovial fluid, and other components allows synovial joints to offer a wide range of motion while maintaining stability and reducing wear and tear on the bones.