1.1.a The structure and function of the skeletal system Flashcards
What are the main functions of the skeletal system?
- Support
- Posture
- Protection
- Movement
- Blood cell production
- Storage of minerals
Support:
Skeleton keeps body upright and provides framework for muscle and tissue attachment.
Posture:
Skeleton gives correct shape for our body
Protection:
Bones of skeleton protects internal organs and reduce risk of injury on impact.
Example of protection in skeletal system (cranium):
Protects the brain
Example of protection in skeletal system (ribs):
Protects hearts and lungs
Example of protection in skeletal system (vertebrae):
Protects the spinal chord.
Example of protection in skeletal system (pelvis):
Protects sensitive reproductive organs
Blood cell production:
Certain bones in the skeleton contain bone marrow which produces white blood cells, red blood cells and platelets.
Movement:
Skeleton allows movement of body.
* Bones from joints and act as levers.
* This allows muscles to produce movement.
* Bones of skeleton provide surface for attachment of muscles.
Examples of minerals the bones store:
Calcium, iron, potassium, phosphorus
Example of bones containing bone marrow:
pelvis, sternum, humerus, femur
Joint definition:
A joint is a place where two or more bones meet and is also called an articulation.
Synovial joints:
Allow us the free movement to perform skills and techniques during physical activity (freely moveable joints)
How cartilage helps synovial joints
The ends of the bones are covered in cartilage which cushions the joint and prevents friction and wear and tear between bone ends.
How do ligaments protect the joint?
Can absorb shock because of their elasticity, which protects the joint.
Four important synovial joint:
- Elbow joint
- Knee joint
- Hip joint
- Shoulder joint
What type of joint is the elbow joint and the knee joint an example of?
Hinge joint
What type of joint is the shoulder joint and the hip joint an example of?
Ball and socket joint
What is a hinge joint?
A type of synovial joint that allows bending and straightening only (works like the hinge on a door)
What is a ball and socket joint?
A type of synovial joint that allows movement in almost every direction.
What are the articulating bones in the elbow joint?
Humerus, ulna, radius
What are the articulating bones in the knee joint?
femur, tibia (fibula and patella are not classed as bones in the knee joint)
Articulating bones in the hip joint:
femur, pelvis
Articulating bones for the shoulder joint:
Scapula, humerus (clavicle is NOT part of the shoulder joint)
flexion
flexion is a decrease in the angle around a joint
extension
When the angle of the bones that are moving (articulating bones) is increased.
Rotation
Rotation is when the bone turns about its longitudinal axis within the joint. Rotation towards the body is called internal or medical rotation, rotation away from the body is external or lateral rotation.
Abduction
Abduction is the movement of the body away from the midline of the body.
Adduction
Adduction is the movement towards the midline of the body
Circumduction
Circumduction is the movement of a body region in a circular manner.
ligaments
Bands of connective tissue that connect bone to bone and stabilise movement
cartilage
Designed to reduce friction and act as a shock absorber for the joint
tendons
connective tissue that attaches muscle to bone
