A joint, or articulation, is the point where two or more bones meet. Joints help the skeleton balance stability with movement: skull joints are designed for strong support, while other joints allow limbs to move.
Structural classification is based on the material connecting the bones and whether a space, or cavity, is present between them. The main structural categories are fibrous, cartilaginous, and synovial joints. Bony joints are another structural category, in which bones are fused together.
All flashcards
What is an articulation?
An articulation is a joint—the place where two or more bones meet. It may provide movement, stability, or both.
What are the three types of fibrous joints?
Sutures, syndesmoses, and gomphoses. They are all held together by fibrous connective tissue, but differ in location and the movement they permit.
How do synchondroses and symphyses differ?
A synchondrosis joins bones with hyaline cartilage, as in a growing bone's epiphyseal plate. A symphysis has fibrocartilage connecting the bones, as between vertebrae.
What does synovial fluid do?
It lubricates the synovial cavity and reduces friction between the articulating bones, helping the joint move.
What do synarthrosis, amphiarthrosis, and diarthrosis mean?
They describe functional movement: synarthroses are immovable, amphiarthroses allow slight movement, and diarthroses allow free movement.
Quiz questions
How are joints distinguished in structural classification?Answer: By the connecting material and whether a cavity is present.
What connects the bones in a syndesmosis?Answer: A band of connective tissue.
Which structure connects a tooth to its socket in a gomphosis?Answer: The periodontal ligament.
What distinguishes a symphysis from a synchondrosis?Answer: A symphysis connects bones with fibrocartilage; a synchondrosis uses hyaline cartilage.
Which functional category describes a freely movable joint?Answer: Diarthrosis.
Based on Biology 2e by Mary Ann Clark, Matthew Douglas, Jung Choi (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.