Muscular Chapter Review

Origin of Biceps Brachii

Long head and short head of the scapula

Insertion of the Biceps Brachii

Fascia of radial and ulnar bones

Action of biceps brachii

Flexes forearm

Origins of the triceps brachii

Long head of scapula, head of humerus, head of humerus

Insertion of triceps brachii

Posterior part of the olecranon process of the ulna

Action of triceps brachii

extends elbow

Origin of deltoid

Far 3rd of clavicle, acromion, spine of scapula

Insertion of deltoid

Middle of far surface of the humerus

Action of the deltoid

abducts arm

Origin of sternocleidomastoid

anterior/superior manubrium, top middle 3rd of clavicle

Insertion of sternocleidomastoid

Lateral side of the mastoid process

Action of sternocleidomastoid

flexes and laterally rotates cervical spine

Origin of Pectoralis Major

Clavicle head, medial ½ clavicle, sternocostal head lateral manubrium and sternum,

Insertion of Pectoralis Major

Bicipital groove of humerus and lip of deltoid tuberosity

Action of Pectoralis Major

Flexes and adducts arm

Origin of Latissimus Dorsi

Spine T7, spinous processes and ligaments of lower thoracic, lunbar and sacral vertebrae

Insertion of Latissimus Dorsi

Floor of bicipital groove of humerus

Action of Latissimus Dorsi

Extends and medially rotates arm

Origin of Trapezius

Medial 1/3 superior nuchal line, spinous processes

Insertion of Trapezius

Upper fibers to far 1/3 of posterior border of clavicle, lower acromion, and superior spine of scapula

Action of Trapezius

Laterally rotates, elevates and retracts scapula

Origin of Rectus Abdominis

Pubic crest and pubic symphysis

Insertion of Rectus Abdominis

5,6,7 costal cartilages

Action of Rectus Abdominis

Flexes trunk

Origin of Quadriceps: Vastus Medialis

Lower spiral line, medial intermuscular septum

Insertion of Quadriceps: Vastus Medialis

Medial quadriceps tendon to patella

Action of Quadriceps: Vastus Medialis

extends knee

Origin of Quadriceps: Vastus Lateralis

Base of greater trochanter, lateral linea aspera

Insertion of Quadriceps: Vastus Lateralis

Lateral quadriceps tendon to patella

Action of Quadriceps: Vastus Lateralis

extends knee

Origin of Quadriceps: Vastus Intermedius

Anterior and lateral surfaces of the femur

Insertion of Quadriceps: Vastus Intermedius

Quadriceps tendon to patella

Action of Quadriceps: Vastus Intermedius

Extends knee

Origin for Quadriceps: Rectus Femoris

Iliac spine, ilium above acetabulum

Insertion of Quadriceps: Rectus Femoris

Quadriceps tendon to patella

Action of Quadriceps: Rectus Femoris

Extends knee, flexes thigh at the hip

Origin of Hamstrings: Semimembranosus

Upper outer ¼ of posterior surface of ischial tuberosity

Insertion of Hamstrings: Semimembranosus

Medial condyle of tibia

Action of Hamstrings: Semimembranosus

Flexes and medially rotates knee, extends hip

Origin of Hamstrings: Semitendinosus

Upper inner ¼ of posterior surface of ischial tuberosity

Insertion of Hamstrings: Semitendinosus

Upper medial shaft of tibia

Action of Hamstrings: Semitendinosus

Flexes and medially rotates knee, extends hip

Origin of Hamstrings: Biceps Femoris

Upper inner ¼ of posterior surface of ischial tuberosity, and the short head; ridge of femur

Insertion of Hamstrings: Biceps Femoris

Head of fibula

Action of Hamstrings: Biceps Femoris

Flexes and laterally rotates knee

Origin of Gastrocnemius

Lateral head of lateral condyle of femur, and the highest lateral condyle

Insertion of Gastrocnemius

Tendon calcaneus

Action of Gastrocnemius

Plantar flexes foot, and flexes knee

Origin of Soleus

Soleal line and middle 1/3 of posterior border of tibia and upper shaft of fibula

Insertion of Soleus

Tendon calcaneus

Action of Soleus

Plantar flexes foot

Origin of Gluteus Maximus

Outer ilium, posterior 1/3 of iliac crest, lateral mass of sacrum, coccyx

Insertion of Gluteus Maximus

Femur, lateral condyle of tibia

Action of Gluteus Maximus

Extends and laterally rotates hip

Origin of Temporalis

Temporal fossa

Insertion of Temporalis

Medial and anterior aspect of coronoid process of the mandible

Action of Temporalis

Elevates mandible

Origin of Frontalis

Occipital nuchal line, mastoid process

Insertion of Frontalis

Galeal aponeurosis

Action of Frontalis

Wrinkles forehead

Origin of Orbicularis Oculi

Medial orbital margin and lacrimal sac

Insertion of Orbicularis Oculi

Inner corner of eye

Action of Orbicularis Oculi

Closes eyelids, passage for drainage of tears

Origin of Orbicularis Oris

Medial surface of maxilla and mandible

Insertion of Orbicularis Oris

Mucous membrane of margin lips

Action of Orbicularis Oris

Narrows mouth

Origin of Buccinator

External margins of maxilla and mandible

Insertion of Buccinator

Decussates at modiolus of mouth and interdigitates with opposite side

Action of Buccinator

Aids in chewing, tenses cheeks

Origin of Zygomaticus

Anterior surface of zygomatic bone

Insertion of Zygomaticus

Modiolus at angle of mouth

Action of Zygomaticus

Elevates and draws angle of mouth laterally

Origin of Depressor Anguli Oris

Outer surface of mandible posterior to oblique line

Insertion of Depressor Anguli Oris

Modiolus at angle of mouth

Action of Depressor Anguli Oris

Depresses and draws angle of mouth laterally

Origin of Masseter

Anterior 2/3 of zygomatic arch and zygomatic process of maxilla

Insertion of Masseter

Lateral surface of angle and lower ramus of mandible

Action of Masseter

Elevates mandible

Muscular System Functions

body movement, body form and shape, maintains posture, body heat - maintain body temperature

Skeletal Muscles

Voluntary, striated, attached to bone, multi-nucleated, nucleus near edges of fibers, long cylindrical fibers

Smooth Muscle

Involuntary, inside internal organs, non-striated, small and spindle shaped, single nucleus, controlled by autonomic nervous system

Cardiac Muscle

Only in heart, involuntary, striations are not clear, branched fibers, intercalated disks connect fibers

Contractility

a muscle’s ability to shorten

Excitability

ability to respond to stimuli

Extensibility

ability to stretch

Elasticity

ability to return to original length when relaxing

Tendon

fibrous bands that connect muscle to bone

Ligaments

fibrous bands that connect bone to bone

Antagonist

pulls from the opposite direction

Prime Mover

muscle that produces movement in one direction