pe Flashcards
functions of the skeletal system
- gives the body its shape
- allows movement
- makes blood cells
- provides protection for organs and stores minerals.
Involuntary muscles
Involuntary muscles, like those that control the beating of the heart, do not require conscious thought to make them move even though their action is still controlled by the nervous system.
Voluntary muscles
Voluntary muscles can be controlled by our conscious thought
e.g. the muscles in our hands as we catch a ball.
How does the skeletal system affect your performance
- supports your weight evenly so you can stand and move with ease
How does the muscular system affect your performance
- controls your heartbeat and breathing
- helps digestion and allows movement
When a muscle shortens or lengthens it is known as
ISOTONIC CONTRACTION
When a agonist muscle shortens under tensions this is know as
CONCENTRIC CONTRACTION
When a muscle lengthens under tension this is known as
ECCENTRIC CONTRACTION
When a muscle contracts is either
Shortens, lengthens or stays the same
Skeletal system is made up of
- Bones
- ligaments
- tendons
- joints
Functions of the vertebral column
- provides attachments to the muscles
- supports the trunk
- protects the spinal and the nerve cord
Different structure and function of joints
- provides flexibility to the skeleton
- provides stability to specific structures such as the skull and pelvis
- directing the motion of bones
Concentric contractions
- lifting a weight, a concentric contraction of the bicep would cause the arm to bend at the elbow, lifting weight to the shoulder
Eccentric contractions
- the controlled lowering of a wight reading during the above contraction
Isometric contraction
- During a bicep curl, holding the dumbbell in contact position rather than actively raising/ lowering it
Muscular system
Network of fibres that work together to create movement by contracting to extending
how many voluntary muscles are there
600 voluntary muscles in out body which makes up 40-50% of our weight
Joints are
A site where two or more bones come together
Fixed/ Fibrous joints
- No movement at all
- No joint cavity
- Bones are half together by tough fibrous tissue
Cartilaginous joint
slight movement
Synovial joint
freely moveable
Classification of joints
- Fibrous
- Cartilaginous
- Synovial
Muscles are attached to bones via
tendons
Movement occurs when
muscles shorten
Muscles responsible for the movement is called the
prime mover
muscles that opposes the movement is called the
antagonist
when muscles contract is either
shortens, lengthens or stays same
Skeletal/ voluntary muscles
- Striped in appearance
- Full control over their use
Smooth/ involuntary muscles
- smooth in appearance
- works without us thinking
- found in walls of internal organs
Skeletal muscles give
- Shape. support to the body
- Allows movement
- Generates heart
Skeletal muscles type 1
- (slow twitch)
- producing lower levels of speed and power
Skeletal muscles type 2
- (fast twitch)
- can contact quickly but have poor endurance capacity
Human skeleton provides
- Us with a complex framework of bones, joints and cartilage without which we could not stand upright or move
how many bone in body
206
bones divide into
- axial
- appendicular skeleton
Support
- Provides shape/ support for the organs and tissues for the body
protection
protection for internal organs
movement
provides large surface area for muscles attachment and allows movement with the bones acting as levers
storage
bones in the skeleton store important minerals- calcium
blood cell production
new blood cells are formed in the red marrow of bone s
Axial skeleton is made up of
- Skull (cranial and facial bones)
- ears
- neck
- back (vertebrae, sacrum and tailbone)
- ribcage (sternum and ribs).
Skull has how many bones
28 which are fused
vertebral column has how many bones
33 bones called vertebrae
sternum
commonly known as the bread is a flat bone which is at the front of the rib cage
ribs
- 12 pairs which join onto the vertebral column
- 3 pairs attached
- 2 unattached- floating ribs
Appendicular skeleton is made up of
- Shoulder girdle
- Upper/lower limb
- hip
Shoulder girdle
- two scapula (shoulder blades)
- two clavicles (collar bones)
upper limb
- made up of humerus ( upper arm bone)
- radius/ulna (lower arm bone)
- 8 carpal bones in wrist
- 5 metacarpals in hand
- 14 phalanges in fingers
lower limb
- legs made up of femur (thigh bone)
- patella (knee cap)
- tibia (shine bone)
- 7 tarsals-foot
- t metatarsals in foot
- 14 phalanges in foot
hip
- 2 halves that are fused together
- bones that make up each side are ilium, ischium and pubis
Speed
rate of change of distance
velocity
rate of change of displacement
acceleration
rate of change of velocity per unit of time
Functions of the muscular system
- Provides framework for your muscles and other soft tissue s
Structure of muscular system
- Composed of specialised cells called muscle fibres
Biomechanical factors in body
- Body position
- Exertions
- Forces
- Motions
1st law of motion
- Law of inertia
- Tendancy of an object at rest to remain at rest or stay in motion unless acted on by an external force
2nd law of motion
- Law of acceleration
- How quickly/ slowly the velocity of an object changes
eg. golf
3rd law of motion
- Law of action/reaction
- whenever one ob jet exerts a force on a second object, the second object exerts equal and opposite force on the first object
eg. base ball
Levers
SImple machine consisting of a solid bar supported by a pivot point designed to help move a load on one end by applying effort on the other
Levers 3 main parts
- The load
- The effort
- The pivot point
First class lever
- Fulcrum is positioned between the resistance and the force
Second class lever
- Resistance is placed between the fulcrum and the force
Third class lever
- Force is placed between the fulcrum and the resistance
Flexion
Bending a joint (close)
Extension
Straightening a joint (open)
Abduction
Movement away from the midline of the body
eg. jumping jacks
Adduction
Movement towards the midline of the body
eg. breaststroke
Circumduction
Limbs move in circle
eg. overarm tennis serve
Vertabral column makes up
2/5 of the total height of the body
Cervical
7 vertebrae
Thoracic
12 vertebrae
Lumbar
5 vertebrae
Sacrum
5 fused vertebrae
Coccyx
4 fused vertebrae
