Skeletal Functions Flashcards
What are the 6 functions of the skeleton?
Support Protection Movement Shape and structure Blood cell production Storage of minerals
Support
The skeleton provides support for the muscles and vital organs; it holds them in place. Without support we would be a mass of soft tissue, unable to move
Example of support
The ribs support the intercostal muscles and hold the lungs in place
Protection
Bones act as rigid shell to protect the vital organs and CNS because they are soft and easily damaged. During exercise protection is crucial for performance and long term health. It reduces injury.
Example of protection
Cranium, a flat bone, protects the brain and spinal column protecting the spinal cord.
Movement
Takes place in joints. Bones provide a surface for muscles to attach via tendons. When muscles contract movement occurs.
Example of movement
Lifting your leg to run, muscles attached to the femur contract pulling it up.
Shape and structure
Without framework, the body would be a mass of soft tissue. The skeleton also provides something for muscles and tendons to attach to. Without shape we would not move.
Example of shape and structure
The vertebral column gives the body height
Blood cell reproduction
Red blood cells, white blood cells and platelets are produced in bone marrow. Red blood cells carry oxygen, white blood cells fight off infection and platelets help blood to clot following an injury
Example of blood cell reproduction
Occurs in long bones such as the femur, tibia, fibula, humerus, radius and ulna
Storage of minerals
Calcium and phosphorus along with other minerals are stored in bones. Their role in exercise is linked to general health of an athlete which affects sporting performance as the minerals are necessary for vital body functions.
Example of storage of minerals
Calcium and phosphorus are needed for strong teeth and bones but calcium is involved in muscular contractions
What are the 4 types of bones in the body?
Long
Short
Flat
Irregular
List the long bones
Arms - Humerus
Radius
Ulna
Metacarpals
Phalanges
Legs - Femur
Tibia
Fibula
Metatarsals
Phalanges
Function of long bones
Enable gross movement
Generate speed and strength
Produce blood cells
List the shorts bones
Hands - Carpals
Feet - Tarsals
Talus
Function of short bones
Finer movement
Shock absorption
Weight bearing
List the flat bones
Cranium Clavicle Scapula Sternum Ribs Pelvis Sacrum
Function of the flat bones
Large
Protects vital organs
List the irregular bones
Vertabrae
Patella
Function of the irregular bones
Shapes and supports the body
Protects spinal cord
What are the 3 classifications of joints?
Fixed/fibrous
Slightly movable/cartilaginous
Freely movable/synovial
Fixed joint
No movement
Known as fibrous joints as the fibres hold the joint together (fuse)
Slightly movable joint
Gaps between the bones usually filed with cartilage (hence the name cartilaginous joints)
Absorb considerable loads
Small movement
Free movable joints
Allow movement in one or more directions Called synovial due to the synovial fluid within the joint to lubricate it Most common joint Reduce wear and tear Absorb shock Reduce friction
Example of fibrous joints
Cranium
Coccyx
Example of cartilaginous joints
Vertabral column
The joint of the Ribs and the sternum which move during breathing
Example of synovial joints
Shoulder Elbow Knee Hip Ankle Fingers Wrist Neck Thumb
List the 6 synovial joints
Ball and socket - hip and shoulders Pivot - neck Hinge - elbow, knee and fingers Condyloid - wrist Saddle - thumb Gliding - ankle
Ball and socket
Round end of the bone fits into the cup shaped socket of another, allowing movement in all directions (greatest range of movement).
Pivot
A ring of bones fits over a peg of another to allow controlled rotation movement
Hinge
Allows movement in one direction (open and close a joint)
Condyloid
Modified version of the ball and socket, one bone sits on another allowing movement backwards and from side to side . Ligaments often prevent rotation.
Saddle
Similar to condyloid joint but the surfaces are concave and convex. Movement occurs backwards and forwards side to side.
Gliding
Allow limited movement over a flat surface in all directions.
What makes up a synovial joint?
Synovial fluid Synovial membrane Joint capsule Cartilage Ligaments Tendons Bursae
Synovial membrane
Lining inside the joint capsule which lubricates the joint as it secretes (releases) synovial fluid
Synovial fluid
Fills the joint capsule and lubricates and nourishes the joint stops them rubbing together
Joint capsule
Tissue that stops the synovial fluid from escaping and encloses, supports and holds the bone together.
Cartilage
Cushions the joint. Acts as a buffer between the bones. Found at the end of the bones.
Ligaments
Tough bands of elastic fibre that attach bone to bone, keeping the joints stable by restricting movement.
Tendons
Very strong non elastic cords that attach muscle to bone.
Bursae
Fluid filled sac floating between the tendon and the bone which reduces friction.
Name the 3 connective tissues
Tendons
Cartilage
Ligaments
Origin tendon
The place where the muscle is attached to the stationary bone
Insertion
The place where the muscles attaches to the moving bone(s)
7 types of movement
Flexion Extension Abduction Adduction Rotation Plantar Flexion Dorsi Flexion
Flexion
Decreasing an angle at a joint bending or closing at a joint
Extension
Increasing an angle at a joint straightening down to 180° considered as opening a joint
Abduction
Moving limbs away from the midline of the body
Adduction
Moving the limbs towards the centre/midline of the body
Rotation
When the limbs move in a circular motion
Plantar flexion
Flexes downwards increasing the angle (pointing your foot down)
Dorsi Flexion
Flexes upwards decreasing the angle (pointing your foot up)
4 muscle types found in the body
Cardiac
Involuntary
Voluntary
Fixator
Cardiac
Unique to the heart the heart contracts and relaxes continuosly without conscious control or effort
Involuntary
The body’s involuntary muscles work our internal organs. They are outside our control.
Voluntary
They are attached to the skeleton and can be controlled. They have fast and slow twitch fibres.
What are the 2 types of muscular contraction?
Isometric - The muscle stays the same length when the activity is being carried out tension occurs but there is NO movement
Isotonic - A muscular contraction where movement occurs and the agonist muscle changes length
Types of isotonic contraction
Concentric - muscle shortens
Eccentric - Muscle lengthens under tension contractions usually occur against gravity acting as a brake NOT relaxing.
Antagonist pairs of muscles
Pairs of muscles that create movement.
Agonists:
Muscle Shortens
Prime mover
Antagonist:
Muscle lengthens
Muscle Relaxes
Fixator
Stabilise a joint
Example of a voluntary muscle
Your arm catching a ball
Example of a involuntary muscle
Your liver
Example of a fixator muscle
Rotator cuff as it stabilises the bicep
