Skeleton Flashcards
Human skeletom
It is endoskeleton, internal skeleton composed of bone and cartilage which are formed by living cells
What do bine a d cartilage contain
Conrain non living mineral substances sucha s calcium phosphates and calcium carbonates
Bones
Hard, rigid and non elastic tissues
Cartilage
Softer than bones, less rigid and slightly elastic
Axial skelefon
Has skull and vertebral column, ribs and sternum
Appendicular skeleton
Pectoral gridle: shoulder and arms
Pelvic gridle: hip and legs
1.Fuction of skeletal system
Support
- raise the bodu from ground
- arrangemnt of bones fives shape to body as whoel
- rigid skelton to support soft parts of body
2.Fuction of skeletal system
Movemnt
- the skelton is jointdd to allow movemnt
- movemnt is acheived by muscles are connected tk the boned
- the bonss act as levers and the muscles contract to pull them in different positions
3.Fuction of skeletal system
Protection
To protect the delicate parts of the body e.g.
Cranium protects the brain
Vertebral colum protects the spinal cord
Rib cage protects the heart and the lungs0
4.Fuction of skeletal system
Production
Of red abd white blood cells in the bone marrow
Types of joints
What are joints
How are they classified
Where two bones meet a joint is formed
Bones can move in relatio to one another at joints
Joints ars classified according ti the degtee of movemnt oissible between the articulating surface
1.Types of joints
Fixed joint
No movemnt permitted
Structures between the bines of the skull
Pelvic gridle
2.Types of joints
Gliding joint
Limited sliding movemnt
The vertebrae of vertebral column
Wrist
3.Types of joints
Pivot joint
Allows nodding and limited head rotation
Neck
4.Types of joints
Hinge joint
Allows movemnt in 1 plane
Elbow , knee
5.Types of joints
Ball and socket
5.Types of joints
Nall and socker
Allows mkbemnt on 2 planes
Shoulder and hip
Bendinb the forearm
.. biceps(flexor) contract and become shorter abd thucker
..triceps(extensor) relax
..ilna and radius pill closer to the humerus
Straightening the forearm
Triceps contract and becime shorter and thucker
Biceos relax
Ulna and radius pull away fro the humerus
How are skeletal muscles attached to bones and hwk they woek
Attached to the projections or ridges in the bones of the forarm by tendons which are non elastic cords that anchor muscles to bones.
One end of the muscle must be attached to the bone that is to be moved while the other end is anchored to part of the skeleton that is to be held stationary with respect to the moving part
How is the movemnt in forearms brought
Movement in foreaem is brought about by the alternate contraction and relaxation of a pair of antagonistic muscles in the forearm
In the forarm the anaygonsitsic pair of flexor extensor muscles are arranged in such a way that when they contract they pull in opposite directions
Structure of forearm
Forarm is made of humerus, the upper arm ,ulna and radius
the wrist and the hand is made of small carpal bones metacarpal and phalanges
The humerus forms a ball and socket joint with the scapula of the shoulder and hinge joint is formed between humerus and ulna at elbow
