In the structural classification of fibrous joints, what is a suture?

• A. A cartilaginous joint where bones are united by hyaline cartilage, allowing slight movement
• B. A freely movable synovial joint characterized by a fluid-filled joint cavity and articular cartilage
• C. A fibrous joint that permits significant movement because the bones are connected by a long ligament
• D. An immovable fibrous joint where adjacent skull bones are tightly united by short, dense connective tissue

Answer: (D)

Verified step by step guidance

1. Understand that fibrous joints are classified based on the type and length of connective tissue that binds the bones together and the degree of movement allowed.
2. Recognize that sutures are a specific type of fibrous joint found only between the bones of the skull.
3. Note that sutures are characterized by short, dense connective tissue fibers that tightly bind adjacent skull bones, making them essentially immovable.
4. Differentiate sutures from other fibrous joints such as syndesmoses, which allow more movement due to longer ligaments, and from cartilaginous or synovial joints, which have different structural features and movement capabilities.
5. Conclude that a suture is an immovable fibrous joint where adjacent skull bones are tightly united by short, dense connective tissue.