The masseter muscle, one of the strongest in the body, is the main muscle of chewing (mastication). The temporalis muscle moves the mandible up and backwards. The mandible is the jaw bone. The lateral pterygoid muscle is involved in mastication, but is not the strongest. 

The procerus is the muscle that wrinkles the nose. It originates from the fascia covering the inferior aspect of the nasal bone and inserts into the skin on the forehead, in between the eyebrows. The frontalis raises the eyebrows and wrinkles the forehead. The buccinator pulls in the cheeks against the teeth. The risorius pulls the mouth into a grimace. 

The orbicularis oculi closes the eyes. It originates from the frontal and lacrimal bones, and from the medial palpebral ligament, which is attached to the frontal process of the maxilla and inserts into the lateral palpebral raphe. The buccinator pulls the cheeks into the teeth, The procerus wrinkles the nose. The depressor labii inferioris pulls the lower lip down.

The nasalis widens the opening of the nose by compressing the nasal cartilages, flaring out the nostrils. The frontalis wrinkles the forehead while the procerus wrinkles the nose. The levator anguli oris raises the corners of the mouth.

The platsyma muscle is responsible for both wrinkling the skin of the neck and pulling the lower lip down. The platysma is superficial to the sternocleidomastoid, originates from the clavicle, and inserts onto the base of the mandible and the skin of the cheek, lower lip and lower mouth. The depressor labii inferioris only pulls down the lower lip. The depressor anguli oris pulls the corners of the mouth down, while the risorius pulls the sides of the mouth into a grimace. 

The sternocleidomastoid muscle is a powerful muscle that inserts at the mastoid process posterior to the ear. It originates down at the clavicle and manubrium and its contraction is the major muscle movement or protrusion one sees when the neck is turned to one side. This muscle also helps in respiration by raising the superior most rib via its attachment to the manubrium. The middle scalene originates from the transverse processes of the lower six cervical vertebrae, and inserts on the superior aspect of the first and second ribs; its function is to elevate the first two ribs, and contralateral rotation of the head. The anterior scalene has the same action as the middle scalene, but its origin is does not include C2, and it inserts only on the first rib. The sternohyoid, as its name suggests, originates on the manubrium of the sternum, and inserts on the hyoid. Its action is depression of the hyoid. Thee three groups of muscle fibers that make up the trapezius work in concert to control movements of the scapula.

Tee lateral pterygoid moves the jaw forward (protraction) and from side to side. The medial pterygoid is responsible for elevating the mandible and closing the mouth. The buccinator sucks the cheeks in towards the teeth and helps during suckling in neonates. Finally, the depressor anguli oris pulls the corners of the mouth down, as in frowning. 

There are 6 muscles that coordinate eyeball movement. They are the inferior oblique, lateral rectus, superior rectus, medial rectus, inferior rectus, and the superior oblique. 

The medial rectus moves the eye to look towards the nose. The superior rectus moves the eye to look up and towards the nose. The lateral rectus moves the eye to look out towards the side. The inferior rectus moves the eye to look down and towards the nose. 

The inferior oblique rotates the eye to look up and to the side. The medial rectus moves the eye to look towards the nose. The lateral rectus moves the eye to look out to the side only. The superior oblique rotates the eye to look down and out towards the side.