SOC 13 Flashcards
5 functions of skeletal system
-protection of vital organs
-muscle attachment
-joints for movement
-storing calcium and phosphorus
-red and white blood cell production
Long bones
Generate movement
Short bones
Weight bearing
Irregular
Protection/generate movement
Flat bones
Protect vital organs/muscle attachment
What is a joint
-place where two or more bones meet
-important for movement and rotation
-extent and freedom of movement varies from joint to joint
Types of joints?
-Pivot
-hinge
-ball and socket
-condyloid
What is a pivot joint
Pivot joints allow bones to rotate. In a pivot joint, one bone shaped like a
cylinder rotates inside another bone or ligament that makes a ring round it. You have three pivot joints in your body: in your wrist, elbow and neck.
What is a hinge joint
joint that allows only backward and forward motion - just like
the hinge on a door. There are three hinge joints: the knee, elbow and ankle.
What is a ball and socket joint
the rounded head of a long bone (the ball) fits into a cup-shaped hole (the socket). Both the hip and the shoulder joints are ball and socket joints. The shoulder joint has more freedom than the hip and is capable of more variety and a bigger range of movement.
What is a condyloid joint
A condyloid joint is similar to a ball and socket joint, but the ball rests against the end of a bone, rather than inside a socket. This allows circular motion.
Flexion
Bending movement that decreases angle in body parts (shoulder hip elbow)
Extension
Straightening movement that increases the angke between body parts
Adduction
Movement that pulls towards midline of body
Abduction
Movement that pulls away from midline of body
