Muscles and functions

Frontalis

Raises the eyebrows

Masseter

Elevates the mandible for chewing

Orbicularis oculi

Closes the eyelid

Occipitalis

Pulls the scalp backward

Sternocleidomastoid

Flexes the neck and rotates the head to the opposite side

Trapezius

Elevates, retracts, and rotates the scapula

Deltoid

Abducts the arm

Pectoralis major

Pulls the humerus across the chest (adduction and flexion)

Pectoralis minor

Depresses and protracts the scapula

Serratus anterior

Protracts the scapula and holds it flat against the ribs

Intercostals

Elevate the ribs (external) and depress them (internal) for breathing

Latissimus dorsi

Extends, adducts, and medially rotates the humerus

Biceps brachii

Flexes the elbow and supinates the forearm

Brachialis

Flexes the elbow

Triceps brachii

Extends the elbow

External abdominal oblique

Rotates and flexes the trunk

Rectus abdominis

Flexes the vertebral column

Gluteus maximus

Extends the hip

Iliopsoas

Flexes the hip

Rectus femoris

Extends the knee and flexes the hip

Biceps femoris

Flexes the knee and extends the hip

Gastrocnemius

Plantar flexes the foot and flexes the knee

Tibialis anterior

Dorsiflexes and inverts the foot