Final answer:
Ankylosis (4) is the correct answer. It refers to a rigid, immovable joint resulting from the fusion of bones, contrasting with the nature of synovial joints, which are designed to allow a range of movements such as gliding, angular, and rotational actions.
Step-by-step explanation:
The correct option : 4
Which refers to a condition where a joint becomes totally rigid and immovable as a result of bone fusion.An explanation for this condition lies in understanding the different types of joints within the human body. Fibrous joints such as sutures in the skull and gomphoses involving teeth and jawbones, are generally immobile. Cartilaginous joints like the pubic symphysis or intervertebral discs allow for slight movement. On the other hand, synovial joints are characterized by a fluid-filled space between the bones, enabling a wide range of motion, such as in the knee or shoulder.
When a synovial or cartilaginous joint experiences an aberrant bone fusion, this results in ankylosis. This fusion diminishes or eliminates the joint's capacity for movement, leading to complete rigidity.Understanding how ankylosis contrasts with natural joint functions can provide insight into certain medical conditions affecting mobility. Normally, synovial joints allow for various movements including gliding, angular, and rotational actions, which are important for everyday activities and overall physical functioning.