Paper 1 Topic 1 (Y10) Flashcards
Functions of the skeletal system
Protection
Blood cell production
Mineral storage
Joints for movement
Muscle attachment
Protection
The skeleton provides protection for vital organs including your heart and vital organs
E.g. If you get hit on the head in hockey your skull will protect your brain
Blood cell production
-Blood cells are produced in bona marrow
-Platelets help blood to Clot
-Red blood cells transport oxygen to working muscles
-White blood cells help fight infection
Mineral Storage
Bones store calcium and phosphorus, two minerals that are vital for developing and maintaining strong and healthy bones
Joints for movement
-Joints are where two or more bones meet
-Joints let the body make a variety of movements
-This can be ‘fine’(such as holding a pen) or ‘gross’ (such as throwing a javelin)
Muscle attachment
Muscles attach to bones via tendons. When the muscle contracts it pulls the bone causing movement.
Classification of bones
-Long bones
-Short bones
-Flat bones
-Irregular bones
Long bones
-Long bones aid movement by working as levers
-Examples: Humerous and femur
-Sport Example: They act as a lever to kick a football
Short bones
-Short bones are associated with weight bearing and provide support
-Example: Carpals and tarsals
-Sport example: Supporting the body weight in a handstand
Flat bones
-Flat bones provide protection and have a large surface area for mucles to attach to
-Examples: Ribs and sternum
-Sport example: The cranium protects the brain if hit by a cricket ball
Irregular bones
-Irregular bones provide protection and allow muscle to attach
-Example: Vertebrae
-Sport example: The muscles attach to the vertebrae allowing a hockey player to bend down for the ball
What is a joint?
A joint is where 2 or more bones meet. Joints allow movement. We need to know about the following types of joints.
Hinge Joint
-Located in the elbow, knee and ankle
-Movement: Flexion and extension, dorsi-flexion and plantar-flexion (pointing with the toes)
Ball and socket joints
-Located in hip and shoulder
-Movement: Rotation, extension, flexion, abduction, adduction
Pivot joints
Located in Neck
Movement: Rotation
Condyloid joint
Located in wrist
Movement: Extension, flexion, circumduction
Flexion
When the angle at a joint decreases
Flexion occurs at hinge, ball and socket and condyloid
Sporting example: Bending the knee back in preparation to kick a football
Extension
When the angle at a joint increases
Extension occurs at aa hinge ball and socket and condyloid joints
Sporting example: At the knee when following through after kicking a football
Adduction
The movement of a limb towards from the middle of the body (your ADDING a body part to your body)
Adduction occurs at ball and socket joints
Sporting example: When moving the arms and legs towards the body during a star jump
Abduction
The movement of a limb Away from the middle of the body
Abduction occurs at ball and socket joints
Sporting example: When reaching out sideways to intercept a basketabll pass
Rotation
When the bone at a joint moves around its own axis, so making a circular movement
Rotation occurs at ball and socket joints
Sporting example: At the shoulder when swimming front crawl.
Circumduction
Movement in the shape of a cone. Allows 360 degree movement
Circumduction occurs at ball and socket joints
Sporting example: at the shoulder when swimming butterfly
Plantar-flexion
The movement of Pointing the toes Plantar-flexion occurs at hinge Joints (ankle)
Sporting example: When a ballet dancer is on their toes
Dorsi-Flexion
The movement of lifting the toes towards the shin Dorsi-flexion occurs at hinge joints (ankle)
Sporting example: When a hurdler lifts the leg to clear the barrier
Ligaments
-Attach bone to bone
-Keep joint stable
-Prevents unwanted movement that might cause injury (e.g.: dislocation)
-Very common injury in team sports
Tendons
-Attach muscle to bone
-Hold the muscle to the bone, so that when the muscle contracts, this can pull on the bone causing movement
-When warming up and stretching –> ligamentsand tendons are important to avoid injury.
Types of muscle
-Cardiac
-Voluntary
-Involuntary
Cardiac muscle
Forms the heart
Cardiac muscle is unconsiously controlled- we do not have to think to make it contract
The cardiac muscle in the heart contracts to pump blood around the body
Voluntary or skeletal muscle
Voluntary muscles are the skeletal muscles that attach via tendons to the
skeleton to allow movement
Voluntary muscles are under consious control – we move them when we
want to
For example the biceps contract when we perform a bicep curl
Involuntary or smooth muscle
Involuntary muscles are found in the organs of the digestive system, circulatory system and urinary system
They contract slowly and rhythmically and are unconsiously controlled – they contract automatically when required by the body
For example involuntary muscles in the blood vessels help regulate blood flow
Deltoid
Location: Top of the shoulder
Role: Abducts arm at the shoulder
Example: Lifting your arms above your head to block the ball in volleyball
Latissimus Dorsi
Location: Side of the back
Role: Adducts the upper arm at the shoulder
Example: Butterfly in swimming
Pectoralis major
Location: Front of the upper chest
Role: Abducts arm at the shoulder
Example: Follow through from a forehand in tennis
External obliques
Location: Between lower ribs and abdomen
Role: Rotates the trunk and helps pull the chest down
Example: Rotating the trunk when throwing the javelin
Biceps
Location: Front of the upper arm
Role: Flexion of the arm at the elbow
Example: Upwards pase of a biceps curl
Triceps
Location: Back of the upper arm
Role: Extension of the arm at the elbow
Example: Straightening the arms during a chest press
Quadriceps
Location: Front of the upper leg
Role: Extension of the leg at the knee
Example: Straightening the leg when kicking a ball
Hamstring
Location: Back of the upper leg
Role: Flexion of the leg at the knee
Example: Bending the leg going over a hurdle
Gastrocnemius
Location: Back of the lower leg
Role: Plantar-flexion at the ankle
Example: Pointing your tip-toes in ballet
Tibialis Anterior
Location: Front of the lower leg
Role: Dorsi flexion at the ankle
Example: Bringing the toes up when doing ski jumping
Hip flexors
Location: Very top of the upper leg
Role: Flexion at the leg at the hip
Example: Lifting your knees high during sprinting
Gluteus Maximus
Location: Buttocks
Role: Extension of the leg at the hip
Example: Lifting your legs back when running
Antagonistic pairs
A pair of muscles that when one contracts (known as the agonist) the other muscle relaxes (known as the antagonist)
vertebral column order (top to bottom)
Cervical, thoracic, lumbar, sacrum, coccyx
Types of muscle fibre:
-Slow twitch - type I
-Fast twitch - type IIa
-Fast twitch - type IIx
Slow twitch - type I
-Low force
-Slow speed of contraction
-High endurance
-Good for activities to keep going without tiring
-Do not produce much power
Fast twitch - type IIa
-Produce high force
-Moderate speed of contraction
-Medium endurance
-More resistance to fatigue than type IIx
-Not as powerful as type IIx or as resistance to fatigue than type IIa
Fast twitch - type IIx
-Very high force
-High speed of contraction
-Low endurance
-Good for explosive actions requiring strength and speed
-Only produce power for a short period of time before getting fatigued
Skeletar and muscular system together
-The skeletal muscular connect to bones and work with conectives tissues to allow movement
-The main purpose is to provide movement
-They can also provide good posture, stability and protection
