Anatomy

covers upper part of the cranium and consist of two muscular parts - frontalis over the frontal bone and occipitalis over the occipital bone

surrounds the eye

encircles the mouth

located in the wall of the cheek

zygomatic arch downward to the corner of the mouth

extends from the chest over the neck to the face

ORIGIN lower border of zygomatic arch

INSERTION lateral surface of mandible

ACTION elevates mandible

over the temporal bone

extends back and downward from the sphenoid, palatine and maxillary bones to the ramus of the mandible

extend forward from the region just below the mandibular conyle to the sphenoid bone.

ORIGIN - Anterior surface of sternum and upper surface of clavicle

INSERTION - Mastoid process of temporal bone

ACTION - Pulls head to one side, flexes neck or elevates sternum

LOCATION - back of neck connecting the base of the skull to the vertebrae in the neck and upper thorax

LOCATION - extends upward from the vertebrae in the neck and thorax to the occipital bone

LOCATION - run longitudinally along the back and can be divided into lateral, intermediate and medial groups.

ORIGIN - occipital bone and spines of cervical and thoracic verebrae

INSERTION - clavicle, spine, and acromion process of scapula

ACTION - rotates scapula; various fibers raise scapula, pull scapula medially, or pull scapula and ahoulder downward

LOCATION - connect the vertebral column to the scapula

ORIGIN - transverse processes of cervical vertebrae

INSERTION - medial margin of scapula

ACTION - elevates scapula

LOCATION - side of the chest

LOCATION - beneath the pectoralis major. extends laterally upward from the ribs to the scapula

LOCATION - the scapula to the middle of the humerus along the medial suface

ORIGIN - Clavicle, sternum and costal cartilages of upper ribs

INSERTION - intertubercular groove of humerus

ACTION - flexes, adducts and rotates arm medially

ORIGIN - Lateral border of scapula

INSERTION - Intertubercular groove of humerus

ACTION - extends, adducts and rotates arm medially

ORIGIN - spines of sacral, lumbar and lower thoracic vertebrae, illiac crest, and lower ribs

INSERTION - intertubercular groove of humerus

ACTION - extends, adducts and rotates the arm mediallly or pulls the shoulder downward and back

known as SITS muscle group - forms rotator cuff

ORIGIN - Acromion process, spine of scapula and the clavicle

INSERTION - deltoid tuberosity of humerus

ACTION - abducts, extends, and flexes arm

ORIGIN - coracoid process and tubercle above glenoid cavity of scapula

INSERTION - radial tuberosity of radius

ACTION - flexes elbow and rotates hand laterally

LOCATION - beneath the biceps brachii, connects the shaft of the humerus to the ulna and is the strongest flexor of the elbow

LOCATION - connects the humerus to the radius

ORIGIN - tubercle below glenoid cavity and lateral and medial surfaces of humerus

INSERTION - olecranon process of ulna

ACTION - exends elbow

LOACTION - ulna and lateral end of the humerus to the radius

LOCATION - connects the ends of the humerus and ulna to the radius

LOCATION - slant downward from the lower ribs to the pelvic girdle and the linea alba

LOCATION - beneath the external oblizue and runs up and forward from the pelvic girdle to the lower ribs

LOCATION - beneath the external and internal obliques, horizontally from the lower ribs, lumbar vertebrae and ilium to the linea alba and pubic bones.

ORIGIN - crest of pubis and symphysis pubis

INSERTION - xiphoid process of sternum and costal cartilages

ACTION - tenses abdominal wall and compresses abdominal contents, also flexes vertebral column

ORIGIN - pubic bone and ischial spine

INSERTION - coccyx

ACTION - supports pelvic viscera and provides sphincterlike action in anal canal and vagina

ORIGIN - Lumbar interverebral discs; bodies and transverse processes of lumbar vertebrae

INSERTION - Lesser trochanter of femur

ACTION - flexes thigh

LOCATION - lateral side of the psoas major

ORIGIN - Sacrum, coccyx, and posterior surface of ilium

INSERTION - posterior surface of femur and fascia of thigh

ACTION - extends hip

LOCATION - partly beneath gluteus maximus and extends from the ilium to the femur

LOCATION - beneath gluteus medius

LOCATION - shaped like a pyramid inferior to gluteus minimus

LOCATION - connects the ilium to the iliotibial tract which continues down to the tibia

LOCATION - from the spine of the pubis to the femur

LOCATION - triangular that runs from the pubic bone to the femur

LOCATION - short, triangular muscle that runs from the pubic bone to the femur

LOCATION - largest adductor in thigh, triangular, connects ischium to the femur

ORIGIN - lowere edge of symphysis pubis

INSERTION - medial surface of tibia

ACTION - adducts thigh and flexes knee

ORIGIN - ischial tuberosity and linea aspera of femur

INSERTION - head of fibula and laeral condyle of tibia

ACTION - flexes knee, rotates leg laterally and extends thigh

LOCATION - back of the thigh toward the medial side connecting he ischium to the proximal end of the tibia

LOCATION - most medially located muscle in the back of the thigh connects the ischium to the tibia

ORIGIN - anterior superior iliac spine

INSERTION - medial surface of tibia

ACTION - flexes knee and hip, abducts and rotates thigh laterally

LOCATION - front and sides of the thigh.

composed of four parts - rectus femoris, vastus lateratlis, vastus medialis, and vastus intermedius

LOCATION - front of the tibia

LOCATION - connects fibula to lateral side of the foot

ORIGIN - lateral condyle of tibia and anterior surface of fibula

INSERTION - dorsal sufaces of second and third phalanges of four lateral toes

ACTION - dorsiflexion and eversion of foot, extends toes

ORIGIN - anterior suface of fibula

INSERTION - distal phalanx of the great toe

ACTION - extends great toe, dorsiflexion and inversion of foot

ORIGIN - lateral and medial condyles of femur

INSERTION - posterior suface of calcaneus

ACTION - plantar flexion of foot, flexes knee

LOCATION - beneath the gatrocnemius and helps form calf of leg

LOCATION - connects the femur to the heel

ORIGIN - poserior suface of tibia

INSERTION - Distal phalanges of four lateral toes

ACTION - plantar flexion and inversion of foot, flexes four lateral toes

LOCATION - deepest of muscles on the back of leg connecting the fibula and tibia to the ankle bones

LOCATION - lateral side of the leg connecting the tibia and the fibula to the foot

dense connective tissue that hold skeletal muscle in position

cordlike fascia that projecs beyond the ends of its muscle fibers that may intertwine with those in the perioseum of a bone

broad, fibrous sheets that may attach to bone or the coverings of adjacent muscles.

• fascia - covers the surface of the muscle
• epimysium - lies beneath the fascia
• perimysium - extends into the structure of the muscle where it separates muscle cells into fascicles
• endomysium - separates individual muscle fibers

• - brain sends signal to neuromuscular junction and neuron releases ACH into the muscle fiber
• - muscle impulse travels into transverse tubules
• - then throughout the sarcoplasmic reticulum
• - Ca+ is released into the sarcoplasm
• - as Ca+ increases it releases troponin tropomyosin from actin binding sites allowing myosin to link with actin

• - acetylcholinesterase degrade ach
• -Ca+ decreases
• - troponin/tropomysin goes back to ends of actin
• - myosin lets go and muscle relaxes

shortening of muscle occurs also called concentric

muscle remains same length

immovable end

movable end

muscle primarily responsible for producing an action

muscles that contract and assist a prime mover

resist a prime mover's action and cause movement in the opposite direction