ANAPHY (MUSCULAR SYSTEM)

KILL MEEEEEEEEEEEE ; for Physiology of Muscles Contraction and Relaxation watch this video: https://www.youtube.com/watch?v=BVcgO4p88AA

Muscle Systems 3 Main Responsibilities

movement, form & shape (maintains posture), maintains body temperature

Why muscles contract

movement of microfilaments

Skeletal Muscle (Location)

wall of the pharynx and esophagus + attached by tendons to bones

Skeletal Muscle (Structure)

muscle fiber and nuclei

Muscle Fiber

long, cylindrical, & multinucleated

contains alternating light and dark striations

Nuclei

located at the edge of fiber

Skeletal Muscle (Function)

contractions which:

occur voluntarily

may be rapid and forceful

stabilizes the joints

Smooth Muscle (Location)

walls of tubular structures and hollow organs

Smooth Muscle (Structure)

long and spindle shaped, no striatrons

Smooth Muscle (Function)

contractions which:

occur involuntarily

rythmic and slow

Cardiac Muscle (Location)

Muscle found in the heart

Cardiac Muscle (Structure)

short, branching fibers with a centrally located nucleus

striations not distinct

Cardiac Muscle (Function)

contractions which:

occur involuntarily

rythmic and automatic

Epimysium

dense connective tissue that surrounds the entire muscle tissue

Muscle fascicle

band of connective tissue that envelops, separates, or binds muscles

Perimysium

connective tissue that surrounds each bundle of muscle fibers

Endomysium

delicate network of connective that surrounds individual muscle fibers

contains the vessels and nerves that supply the muscle fibers

Muscle fiber

each muscle cell is known as __

Sarcolemma

the cell membrane

Myofibril

a basic rod-like organelle of a muscle cell

Filaments

a long thread comprised of protein subunits

Striations (Bands)

organization of actin and myosin filaments that produces __

Sacromeres

the thick (myosin) and the thin (actin) filaments that are organized into structural units

Contractility

ability of the muscle to contract and generate force when stimulated by a nerve

Excitability/Irritablity

ability of the muscle to respond to certain stimuli by producing electric signals called action potential (impulse)

Extensibility

ability of the muscle to be stretched

Elasticity

ability of the muscle fibers to return to their normal length after being shortened or stretched

Flexor

decrease angle at a joint

Extensor

increase angle at a joint

Abductor

move bone away from midline

Adductor

move bone toward midline

Levator

produce upward movement

Depressor

produce downward movement

Supinator

turn palm upward/anterior

Pronator

turn palm downward/posterior

Muscles of Expression

these muscles lie within the layers of superficial fascia

these muscles move the skin rather than the joint

Frontalis

surprise

raises eyebrow

wrinkles forehead

Orbicularis oculi

sadness

closes the eyelid

tightens the skin on the forehead

Nasalis

muscles of the nose

closes & opens the nasal openings

Zygomaticus major

laughing or smiling

raises corner of the mouth

Orbicularis oris

kissing, puckering

compresses and closes the lips

Depressor anguli oris

doubt, disdain, contempt, frowning

depresses corner of the lip

Platysma (cut)

horror

draws corners of mouth downward and backward

Muscles of mastication

muscles that move the mandible

attached to the skull and bone

Temporalis

raises the jaw

closes the mouth

draws the jaw backward

Masseter

closes the jaw

Sternocleidomastoid

flexes head

rotates the head opposite side from muscle

Trapezius

moves the shoulder

extends the head

Muscles of upper extremities

help move the scapula, humerus, wrist, hand, and fingers

Anterior compartment muscles

originates on the humerus insert on to the carpals, metacarpals, and phalanges

flexor muscles

Posterior ccompartment muscles

arise on the humerus and insert on the metacarpals and phalanges

extensor muscles

Deltoid

covers the shoulder joint

abducts the upper arm

Pectoralis major

anterior part of the chest

flexes the upper arm and helps abduct the upper arm

Triceps brachii

posterior arm to ulna

extends the lower arm

Biceps brachii—short head

flexes the lower arm

Biceps brachii—long head

flexes the lower arm

Pronator teres

Brachialis

primary flexor of the elbow

Brachioradialis

Flexor carpi radialis (Superficial)

moves the hand

Palmaris longus (Superficial)

Flexor carpi ulnaris (Superficial)

moves the hand

Flexor digitorum (Superficial)

moves the fingers

Internal abdominal oblique

Transverse abdominis

Serratus anterior

fan shaped muscle at the lateral wall of the thorax

Diaphragm

Rectus abdominis

External abdominal oblique

Adductor longus

Rectus femoris

Vastus lateralis

Vastus medialis

Peroneus longus

Tibialis anterior

Gluteus maximus

muscle forms the buttocks; extends femur and rotates it outward

Adductor magnus

Semitendinosus

Biceps femoris (long head)

Biceps femoris (short head)

Semimembranosus

Plantaris

Gastrocnemius

calf muscle; points toes and flexes the lower leg

Soleus