URI BIO 221 Practical 3 - Muscles

Occopitofrontalis (Frontal Belly)

Origin: Epicranial aponeurosis

Insertion: Skin of eyebrow, bridge of nose

Action: Raise eyebrows, wrinkle forehead

Occopitofrontalis (Occipital Belly)

Origin: Superior nuchal line

Insertion: Epicranial aponeurosis

Action: Retract scalp

Orbicularis Oculi

Origin: Medial margin of orbit

Insertion: Skin around eyelids

Action: Close eyes

Levator Labii Superioris

Origin: Inferior margin of orbit

Insertion: Orbicularis oris

Action: Elevates upper lip

Depressor Labii Inferioris

Origin: Mandible

Insertion: Skin of lower lip

Action: Depresses lower lip

Orbicularis Oris

Origin: Maxilla, mandible

Insertion: Lips

Action: Compresses, purses lips

Mentalis

Origin: Mandible

Insertion: Skin of chin

Action: Protrudes lower lip

Sternocleidomastoid

Origin: Clavicle, sternum

Insertion: Mastoid process, temporal bone

Action: Bilateral cervical flexion, unilateral lateral flexion, unilateral contralateral rotation

Inferior Rectus

Origin: Sphenoid

Insertion: Inferior surface of eye

Action: Inferior gaze

Superior Rectus

Origin: Sphenoid

Insertion: Superior surface of eye

Action: Superior gaze

Medial Rectus

Origin: Sphenoid

Insertion: Medial surface of eye

Action: Medial gaze

Lateral Rectus

Origin: Sphenoid

Insertion: Lateral surface of eye

Action: Lateral gaze

Superior Oblique

Origin: Sphenoid

Insertion: Superolateral surface of eye

Action: Eye rolls, inferior gaze

Inferior Oblique

Origin: Maxilla

Insertion: Inferolateral surface of eye

Action: Eye rolls, superior gaze

Zygomaticus Major

Origin: Zygomatic bone

Insertion: Lateral aspect of mouth

Action: Elevates corner of lip, draws it laterally

Zygomaticus Minor

Origin: Zygomatic bone

Insertion: Upper lip

Action: Elevates upper lip

Temporalis

Origin: Temporal bone

Insertion: Coronoid process of mandible

Action: Elevates, closes mandible

Masseter

Origin: Zygomatic arch

Insertion: Mandibular angle

Action: Elevates, closes mandible

Diaphragm

Origin: Xiphoid process, costal cartilage, ribs, lumbar vertebrae

Insertion: Central tendon

Action: Flattens, increases vertical dimensions of thoracic cage

External Intercostals

Origin: Inferior border of superior rib

Insertion: Superior border of inferior rib

Action: Elevates ribs

Internal Intercostals

Origin: Superior border of inferior rib

Insertion: Inferior border of superior rib

Action: Depresses ribs

Rectus Abdominis

Origin: Pubic crest, pubic symphysis

Insertion: Ribs 5-7, xiphoid process

Action: Trunk flexion, abdomen compression

External Oblique

Origin: Lower ribs

Insertion: Iliac crest, linea alba

Action: Bilateral trunk flexion, unilateral trunk lateral flexion, abdomen compression

Internal Oblique

Origin: Iliac crest

Insertion: Lowest 3 ribs, linea alba

Action: Bilateral trunk flexion, unilateral trunk lateral flexion, unilateral ipsilateral rotation, abdomen compression

Transverse Abdominis

Origin: Iliac crest, thoracolumbar fascia

Insertion: Xiphoid process, linea alba

Action: Abdomen compression

Erector Spinae

Origin: Sacrum, iliac crest

Insertion: Vertebrae, ribs, base of skull

Action: Bilateral trunk extension, unilateral trunk lateral flexion and rotation

Tendon

Fascia

Epimysium

Blood Vessels

Perimysium

Muscle Fascicle

Endomysium

Muscle Fiber

Capillary

Motor Neuron

Sarcolemma

Myofibril

Sarcomere

I Band

A Band

H Band

Z Line

M Line

Actin

Myosin

T-Tubules

Terminal Cisterna

Sarcoplasmic Reticulum

Skeletal Muscle

Skeletal Muscle

Skeletal Muscle

Cardiac Muscle

Cardiac Muscle

Cardiac Muscle

Smooth Muscle

Smooth Muscle

Smooth Muscle

Nucleus

Striation

Pectoralis Major

Origin: Clavicle, sternum, costal cartilage

Insertion: Greater tubercle of humerus

Action: Shoulder flexion, adduction, medial rotation

Latissimus Dorsi

Origin: Spinous process of thoracic, lumbar, and sacral vertebrae

Insertion: Intertubercular groove of humerus

Action: Shoulder extension, adduction, medial rotation

Trapezius

Origin: Occiput, spinous process of thoracic vertebrae

Insertion: Clavicle, scapular spine, acromion

Action: Scapular upward rotation, scapular retraction, scapular depression

Deltoid

Origin: Clavicle, scapular spine, acromion

Insertion: Deltoid tuberosity of humerus

Action: Shoulder flexion/extension, abduction, medial/lateral rotation

Supraspinatus (RC)

Origin: Supraspinous fossa of scapula

Insertion: Greater tubercle of humerus

Action: Shoulder abduction, lateral rotation

Infraspinatus (RC)

Origin: Infraspinous fossa of scapula

Insertion: Greater tubercle of humerus

Action: Shoulder lateral rotation

Teres Minor (RC)

Origin: Lateral scapular border

Insertion: Greater tubercle of humerus

Action: Shoulder extension, adduction, lateral rotation

Subscapularis (RC)

Origin: Subscapular fossa of scapula

Insertion: Lesser tubercle of humerus

Action: Shoulder extension, adduction, medial rotation

Supraspinatus (RC)

Infraspinatus (RC)

Teres Minor (RC)

Teres Major

Subscapularis (RC)

Teres Major

Origin: Inferior angle of scapula

Insertion: Intertubercular groove of humerus

Action: Shoulder extension, adduction, medial rotation

Biceps Brachii (Long Head)

Origin: Supraglenoid tubercle of scapula

Insertion: Radial tuberosity of radius

Action: Shoulder flexion, elbow flexion, supination

Biceps Brachii (Short Head)

Origin: Coracoid process of scapula

Insertion: Radial tuberosity of radius

Action: Shoulder flexion, elbow flexion, supination

Biceps Brachii

Brachialis

Origin: Distal humerus

Insertion: Ulnar tuberosity

Action: Elbow flexion

Brachialis

Triceps Brachii (Long Head)

Origin: Scapula

Insertion: Olecranon process of ulna

Action: Shoulder extension, shoulder adduction, elbow extension

Triceps Brachii (Lateral Head)

Origin: Humerus

Insertion: Olecranon process of ulna

Action: Elbow extension

Triceps Brachii (Medial Head)

Origin: Humerus

Insertion: Olecranon process of ulna

Action: Elbow extension

Triceps Brachii

Brachioradialis

Origin: Humerus

Insertion: Radial styloid process

Action: Elbow flexion

Pronator Teres

Origin: Medial epicondyle of humerus, radius

Insertion: Radius

Action: Forearm pronation, elbow flexion

Flexor Carpi Radialis

Origin: Medial epicondyle of humerus

Insertion: Metacarpals II/III

Action: Wrist flexion, radial deviation

Palmaris Longus

Origin: Medial epicondyle of humerus

Insertion: Palmar aponeurosis

Action: Wrist flexion

Flexor Carpi Ulnaris

Origin: Medial epicondyle of humerus

Insertion: Pisiform, hamate, metacarpal V

Action: Wrist flexion, ulnar deviation

Extensor Digitorum

Origin: Lateral epicondyle of humerus

Insertion: Distal and middle phalanx II-V

Action: Phalangeal extension, wrist extension

Supinator

Origin: Lateral epicondyle of humerus

Insertion: Radius

Action: Supinates forearm

Psoas Major

Origin: Transverse processes of lumbar vertebrae

Insertion: Iliacus tendon, lesser trochanter of femur

Action: Hip flexion, lumbar flexion

Psoas Major

Iliacus

Origin: Iliac fossa, sacrum

Insertion: Psoas major tendon, lesser trochanter of femur

Action: Hip flexion

Iliacus

Gluteus Maximus

Origin: Iliac crest, sacrum, coccyx

Insertion: IT band, gluteal tuberosity of femur

Action: Hip extension, lateral rotation

Gluteus Maximus

Tensor Fascia Latae (TFL)

Origin: Iliac crest of ilium

Insertion: Tibia via the IT band

Action: Assists in hip flexion, abduction

Tensor Fascia Latae (TFL)

Gracilis

Origin: Pubic bone

Insertion: Medial shaft of tibia

Action: Hip adduction, medial rotation, knee flexion

Gracilis