MedCerts Muscular System

Muscle Tissue

The only tissue of the human body that can convert chemical energy to mechanical energy

Skeletal muscle cells (fibers)

Very long yet microscopically small cells. Designed to generate a lot of power quickly

Excitability

The ability of muscle tissue to receive nerve stimuli and respond to them by contracting

Contractility

The ability of muscle tissue to shorten when stimulated

Extensibility

Thr ability of muscle tissue to be stretched

Elasticity

The ability of muscle tissue to recoil to resting length

Skeletal muscle contraction

Generates power that the muscle uses to overcome resistance

Abduction

Movement away from the midline

Adduction

Movement towards the midline

Flexion

Decreasing the angle of a joint

Extension

Increasing the angle of a joint

Duchenne muscular dystrophy

A rapidly progressive muscular dystrophy that affects mostly young boys (3-5 years)

Amyotrophic Lateral Sclerosis

or Lou Gehrig's disease

ALS

Muscle weakness and atrophy caused by death of nerve cells. Progresses fairly quickly

Ab-

Meaning: move away (from)

Example: abduct (to move away from the midline of the body)

Ad-

Meaning: move toward

Example: adduct (to move toward the midline of the body)

Alg(o)-

Alge-

algesi(o)-

Algi(o)-

-algia

Meaning: pain

Example: myalgia (pain in a muscle)

Dors(i)-

Dors(o)-

Meaning: back (of the body)

Example: dorsal (relating to the back of the body)

Fasci(o)-

Meaning: fascia

Example: faciitis (inflammation of a fascia)

-gram

Meaning: picture, recording

Example: myogram (graphic representation of a muscle contraction)

-lysis

Meaning: breakdown, destruction, separation

Example: rhabdomyolysis (breakdown of muscle fibers)

My(o)-

Myos(o)-

Meaning: muscle (tissue)

Example: myositis (inflammation of muscle tissue)

-necrosis

Meaning: tissue death

Example: osteonecrosis (death of bone tissue)

-pathy

Meaning: disease, feeling

Example: myopathy (any disease affecting muscles)

Plant(i)-

Plant(o)-

Meaning: sole of the foot

Example: plantar (relating to the sole of the foot)

Rhabdomy(o)-

Meaning: skeletal muscle

Example: rhabdosarcoma (cancer of skeletal muscle)

Ten(o)-

Tend(o)-

Tendin(o)-

Meaning: tendon

Example: tendinitis (inflammation of a tendon)

Epimysium

The outermost connective tissue sheath that wraps around a whole muscle, helps transfer the force/power generated by a muscle contraction

ATP

Adenosine triphosphate, is the form of energy muscle tissues uses for muscle contraction

Endurance (aerobic respiration)

Challenges the muscle to increase its blood supply. Leads to greater endurance, strength, and fatigue resistance. Does not increase the muscle size.

Resistance exercise

Leads to an increase in muscle size by pushing the muscles beyond their limit

Oxidative fibers

Use the aerobic metabolic pathway

Glycolytic fibers

Use glycolysis metabolic pathway

Fast glycolytic fibers

Are fibers that use glycolysis to generate ATP quickly and contract quickly. These fatigue easily from lactic acid build-up

Slow oxidative fibers

Generating ATP using oxygen in the aerobic pathway takes time, which is why these fibers are called slow

Fast oxidative fibers

Some oxidative fibers can use ATP faster than others, hence why they’re fast

Origin

A muscle attaches to a bone that remains immobile for an action

Insertion

A muscle attaches on a bone that moves during the action

Gliding movements

Occur at flat bone surfaces, when one flat bone glides or slips over another

Example: waviyour hand left to right

Angular movements

Increase or decrease the angle between the bones of a joint

Flexion

Decreases the angle of a joint

Extension

Increases the angle of a joint

Hyperextension

Excessive extension beyond the normal range of motion

Abduction

Movement away from the midline

Adduction

Movement towards the midline

Dorsiflexion

Upward movement of the foot

Plantar flexion

Downward movement of the foot

Inversion

Turning the sole of the foot medially

Eversion

Turning the sole of the laterally

Protraction

Anterior movement of a body part in the horizontal plane

Retraction

Posterior movement of a body part in the horizontal plane

Elevation

Lifting a body part superiorly

Depression

Moving a body part inferiorly

Opposition

Movement in the saddle joint so that the thumb touches the tips of the other fingers

Rotation

Turning of a bone around its own axis

Pronation

Turning the hand forward

Supination

Turning the hand backward

Prime movers (agonists)

Provide most of the force for a specific movement

Antagonists

Oppose or reverse a particular movement

Synergists

Add force to a movement or reduce undesirable or unnecessary movement

Fixators

Immobilize a bone or muscles origin

Flexors

Move the joint-forming bones toward eachother

Extensors

Stretch the joint by moving the joint-forming bones away from eachother