The head and the eye consists of the brain, eye, cranial nerves. muscles, cranium bones and skin, among others. There are many more components, however I will only lightly touch upon the major ones.
Primary center for regulating and coordinating body activities, in the human adult it weighs about 3lbs and has many parts that control many different parts of the body.
Frontal Lobe:
Function-Thought Processes, behavior, personality and emotion.
-Broca area: Motor Speech
-Temporal Lobe: Hearing, smell
-Parietal Lobe: body sensations
-Occipital Lobe:Vision
Wernicke's area: Language Comprehension
Cranial Nerves and functions:
Olfactory- smell
Optic- Vision
Oculomotor- Eye Movement
Trochlear- Eye Movement
Trigeminal
-Opthalmic- Face/Scalp sensation
-Maxillary- Mouth/nose sensation
-Mandibular- Chewing
Abducens- eye movement
Facial-Face/scalp movement, tongue (taste)
Vestibulocochlear-hearing,/equilibrium
Glossopharyngeal- ear pain/temp., tongue/throat
Vagus- throat, voicebox..etc..
Accessory- neck/back movement
Hypoglossal- Tongue movement
Head Muscles:
Orbicularis Oculi- Closes eyelids, wrinkles forehead
Masseter- Closes Jaw for Chewing
Sternocleidomastoid- Turns head (on neck)
Skin:
Protective membrane over the entire body, skin guards deeper tissues against loss of water, salts, heat and against invasions of pathogens and their toxins.
Skin contains 2 types of glands:
sebaceous- produces an oily secretion called Sebum
Sweat Glands- watery secretion called sweat
The 3 layers of the skin:
Epidermis
Dermis
and Subcutaneous
Head:
Bones of the skull protect the brain and the structures related to it, like the sense organs. Muscles for controlling head movements and chewing motions are connected to the cranial bones. The cranial bones join each other at the joints called sutures.
Bones of the Cranium:
Frontal
Parietal
Temporal
Occipital
Sphenoid
Ethmoid
Jaw:
Mandible (lower)
Maxillary (upper)
All the facial bones except one, are joined together by sutures so that they are immovable. The mandible is the only facial bone capable of movement.
The major parts of the eye:
Pupil
Retina
Conjunctiva
Cornea
Sclera
Iris
Optic Nerve
Macula
Rods and Cones
The eye is a sense organ with receptors whose sensitive cells may be activated by a particular form of energy or stimulus in the external or internal environment. The sensitive cells in the eye response to stimulus by initiatin a series of nerve impulses along afferent sensory neurons that lead to the brain.
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