Functional anatomy Flashcards
Muscle Types
- Skeletal Muscle
- Cardiac Muscle
- Smooth Muscle
Skeletal Muscle Function
- Permit movement
- Posture
- Blood circulation
Cardiac Muscle Function
Muscles in the heart used to pump blood
Smooth Muscle function
- Blood passageways (arteries, veins) to effect the pressure inside the vessel
- Perform a variety of essential tasks within organs e.g. maintaining structure in the intestines and contracting to push thru food
Muscle Characteristics
- Excitability
- Contractibility
- Extensibility
- Elasticity
Excitability
Ability for muscles to receive a stimulus, usually a neural impulse but can be a reflex from interneurons
Contractability
The ability for muscles to shorten in response to a stimulus (all or nothing principle)
All or nothing principle
A tendon in a muscle will either contract 100% or 0% when contracting, having many tendons allows the body to control how far the entire muscle is contracted
Extensability
The ability for a muscle to extend past it’s normal resting length, usually about 1.5x depending on the muscle
Elasticity
The ability for a muscle to return to original resting length after stretching
Posterior/Anterior
Reference points for muscles
Posterior is behind/backwards
Anterior is the front
Superior/Inferior
Reference points for muscles
Superior is above
Inferior is below
Proximal/Distal
Reference points for muscles
Proximal is towards the limb attachment points
Distal is away from limb attachment/further to end of limb
Medial/Lateral
Reference points for mucles
Medial is closer to the midline of the body (med - mid)
Lateral is further out from the midline
Superficial/Deep
Reference points for muscles
Superficial is closer to the surface of the skin
Deep is further in from the skin
Abduction
Movement of joints away from the midline
Adduction
Movement of joints towards midline
Extension
Movement of joints to decrease the angle that is present - mostly straightening the joint
Flexion
Movement of joint to increase the angle that is present - mostly bending the joint
Rotation
Bending a joint around its own longitudinal axis e.g. rotating the shoulder
Circumduction
joint movement where the end of the joint traces a circle in the air - combination of flexion and extension