Muscular System Revision

Cardiac Muscle

Skeletal Muscle

Smooth Muscle

Nervous Muscle

To bind to the myosin head

To expose binding sites on actin

To pull the thin filament towards the center of the sarcomere

To hydrolyze and move myosin back to its original position

Muscle length stays the same whilst contracting

Muscle length increases during contraction

Muscle length decreases during contraction

Muscle length varies during contraction

They lengthen

They shorten

They stay the same

They relax

Concentric

Eccentric

Isometric

Static

Origin of the muscle is the end attached to the scapula

Insertion of the muscle is the end attached to the scapula

Origin of the muscle is the end attached to the radius

Insertion of the muscle is the end attached to the radius

Muscles

Bones

Type of movement

Sporting example

Agonist

Synergist

Fixator

Antagonist

rhomboids /

serratus anterior

levator scapulae /

pec minor

biceps / brachioradialis

pectoralis major / deltoid

Rich blood supply

Limited anaerobic substrate storage

Many mitochondria and myoglobin

Low intensity, longer-duration activities

Uses only glycolytic respiration

Fatigues slower than slow-twitch fibers

Can perform powerful movements multiple times

More reliant on oxygen than slow-twitch fibers

Low mitochondria and myoglobin

Uses ATP-PC quickly and re-synthesizes slowly

Used in sports with quick bursts of power

High endurance and low force production

Slow-Twitch (ST)

Fast-Twitch A (FT-A)

Fast-Twitch B (FT-B)

All have the same resistance

It states that a muscle can contract partially

It states that a muscle will only contract if it receives a nerve impulse

It states that all muscle fibers will contract regardless of the stimulus

It states that a muscle can contract without a nerve impulse

Slow

thin filaments

thick filaments

transverse tubules

motor end plates

increases

decreases