AEMCA Practice Exam

Which statement is true regarding synarthroses joints?

1. They are freely movable

2. They are slightly movable

3. They are immovable

4. They are always cartilaginous

The correct answer is: They are immovable

Synarthroses joints are characterized by being immovable. This type of joint is primarily found where stability is necessary, and the rigid structure helps to maintain the integrity of the bony connections involved. An example of synarthroses joints can be seen in the sutures of the skull, where the bones are closely fitted together by fibrous tissue, providing both protection and support to the brain. The immobility of these joints is crucial for functions such as protecting vital organs and allowing for the proper positioning of bones during growth and development. The other choices imply different degrees of movement. Freely movable joints refer to diarthroses, which allow a wide range of motion, while slightly movable refers to amphiarthroses, which permit some degree of movement. The statement that they are always cartilaginous is misleading since synarthroses can also be fibrous, as seen in the example of cranial sutures. Therefore, the defining feature of synarthroses is indeed their immovability, illustrating their role in providing stability rather than flexibility.