7.4

ligament

segments of tough connective tissue that join bones to other bones or serve to hold organs in place

rheumatoid arthritis

a painful and crippling form of arthritis in which the synovial membrane of a joint is attacked by the immune system, making the join stiff and extremely painful

joint

a place where two bones join together, or articulate

arthritis

an inflammation of a joint or joints

dislocation

an injury in which the bones at a joint pop out of alignment and must be relocated

sprain

an injury that occurs when the ligaments of a joint are over stressed, causing them to become tender and inflamed

Which type of freely movable joint allows the greatest range of motion?

ball-and-socket joint

Give an example of a freely movable joint, a slightly movable joint, and an immovable joint.

joint between humerus and ulna, vertebrae, joints in your skull

synovial fluid

a clear, water-based lubricant, resembling egg white in appearance and consistency, that lubricates a freely movable joint

osteoarthritis

a degenerative disease in which years of wear and tear on a joint cause the articular cartilage in the joint to deteriorate, making the joints stiff and sore

How does osteoarthritis help to reveal the importance of articular cartilage in freely movable joints?

because osteoarthritis is when the articular cartilage breaks down and your bones scrape each other which is painful

In a paragraph, explain the design of a freely movable joint and describe the types of movements for which each type of synovial joint is designed .

hinge- allows bone to move back and forth, ball-and-socket- allows a bone to move in two planes and rotate in place, pivot- bone rotates in place against another bone, ellipsoid- allows movements in two planes but do not permit the bone to rotate in place, gliding- on bone slides across the surface of another, saddle- allows motion in two planes, allowing you to hold your thumb against the side of your hand

What is the most common type of arthritis? Which type is most serious?

osteoarthritis, rheumatoid