Major Muscles and Function

Frontalis

Wrinkles the forehead and raises the eyebrows

Orbicularis oculi

Closes the eyelid

Orbicularis oris

Forms a circle around your mouth and allows you to purse your lips and kiss

Zygomatic major

Elevates lateral corner of the mouth (smiling muscle)

Buccinator

Compresses the cheek to keep food between teeth

Platysma

Tenses skin of the neck, pulls the jaw (mandible) down

Masseter

Closes the jaw, main chewing muscle

Temporalis

Closes the jaw, main chewing muscle

Medial and lateral pterygoid

Move the jaw to the side and forward, chewing muscles for grinding movement

Sternocleidomastoid

Flexes the neck, rotates head to opposite side

Trapezius

Raises the arm and pulls the shoulder downwards

Latissimus dorsi

Extends, addicts, and rotates the arm inward

Pectoralis major

Pulls the arm across the chest, rotates and abducts the arm

Deltoid

Abducts and extends the arm at the shoulder

Rotator cuff muscles

Rotate the arm medially or laterally, assist in keeping the humeral head in the glenoid cavity

Biceps brachii

Prime mover for flexion of the arm at the elbow

Brachialis

Prime mover for flexion of the arm at the elbow

Brachioradialis

Flexes the elbow joint, supinates the forearm and the hand at radioulnar joint

Triceps brachii

Prime mover for extension of the arm at the elbow

Pronator teres

Prorated the forearm by rotating it medially

Iliopsoas

Prime mover for flexion of the thigh

Gluteus maximus

Prime mover for extension of the thigh

Gluteus medius and minimus

Abduct and medially rotate the thigh

Quadriceps femoris

Prime mover for extension of the leg at the knee joint

Hamstrings

Prime mover for extension of the thigh at the hip joint and flexion of the leg at knee joint

Sartorius

Flexes the leg and the thigh, abducts and rotates thigh laterally, allows us to sit cross-legged

Adductor longus and magnus

Adduct the thigh and rotate the thigh laterally

Gracilis

Adducts the thigh at the hip joint, flexes the leg at the knee joint

Tibialis anterior

Dorsiflexes the ankle, inverts the foot and ankle

Gastrocnemius

Plantar flexes the foot at the ankle, raises the heel during walking, flexes the leg at knee joint

Soleus

Plantar flexes the foot at the ankle

Diaphragm

Is the most important muscle for breathing in, separates the thoracic and abdominopelvic cavity

Bulbospongiosus (bulbocavernosus)

Males: assists emptying of urethra, propels semen out during ejaculation, assists in the erection of the penis

Females: assists in the erection of the clitoris, helps the vagina constrict

Suprahyoid muscles

Are mainly involved in swallowing, form the floor of the mouth, anchor the tongue, move the larynx (voice box)