1. SENSES (EYE & EAR) & INTERGUMENTARY SYSTEM (SKIN)

2. The Senses

3. General Senses Distributed throughout body  Pain  Touch  Pressure  Temperature  Proprioception

4. Special Senses Located within complex sense organs Gustation = sense of taste Olfaction = sense of smell Hearing Equilibrium Vision

5. The Ear Illustrated

6. The Ear Used for both hearing and equilibrium Divided into three parts  Outer ear Pinna (auricle) External auditory canal (meatus)  Contains cerumen (earwax) Tympanic membrane (eardrum)  Transmits sound waves to middle ear

7. The Ear (con’t) Middle ear  Houses three ossicles Malleus (hammer) Incus (anvil) Stapes (stirrup)  Soundwaves are transmitted from footplate of stapes  Eustachian tube Connects middle ear to nasopharynx Equalizes pressure between outer and middle ear

8. The Ear (con’t) Inner ear  Complex labyrinth shape  Filled with fluid  Contains cochlea Organ of Corti  Vestibular apparatus Sense of equilibrium Semicircular canals  Vestibulocochlear nerve Cochlear branch transmits hearing impulses Vestibular branch transmits equilibrium impulses

9. Otitis Inflammation of the ear  Otitis media = infection leading to accumulation of fluid in middle ear Causes  Obstruction of eustachian tube caused by  Spreading infection Treatment  Antibiotics  Myringotomy

10. Otitis (con’t)  Otitis externa Inflammation of external auditory canal Also known as “swimmer’s ear” Caused by:  Fungus  Bacterium Common among:  People living in hot climates  Swimmers

11. Meniere Disease Involves production and circulation of inner ear fluid Symptoms  Vertigo (dizziness)  Hearing loss  Tinnitus (ringing in ears)  Pressure Treatment  Drugs (to treat nausea and dizziness)  Severe cases Inner ear or eighth cranial nerve destroyed surgically

19. The Eye and Vision Eye has three layers  Sclera Outermost layer Known as “White of the eye” Extends over front of eye as transparent cornea

20. Eye Illustrated

21. Uvea  Middle, vascular layer  Consists of: Choroid Ciliary body  Muscle controls shape of lens  Allows for accommodation Iris  Muscular ring  Controls size of pupil  Determines eye color

22. Retina Innermost layer Actual visual receptor Consists of specialized cells:  Rods Function in dim light Low visual acuity Do not respond to color  Cones Active in bright light High visual acuity Respond to color

23. Eye Protection Orbit = bony socket Eyelids  Conjunctiva Thin membrane Covers anterior portion of eye Eyebrows Eyelashes Tears Lacrimal glands  Bathe eyes with lubricating fluid  Fluid drains into nose

24. Errors of Refraction Myopia = nearsightedness  Eyeball too long  Images form in front of retina Hyperopia = farsightedness  Eyeball too short  Images form behind retina Astigmatism = irregularity in curve of cornea or lens Glasses can correct most of these impairments

25. Infection Conjunctivitis = inflammation of conjunctiva  Commonly known as “pinkeye”  Highly infectious Trachoma = inflammation of cornea and conjunctiva  Results in scarring  Common cause of blindness in 3 rd world countries Ophthalmia neonatorum = acute conjunctivitis in newborns  Caused by gonorrhea

26. Disorders of Retina Retinal detachment  Separation of retina from choroid  Caused by: Tumor Hemorrhage Injury to eye Repaired with laser surgery

27. Cataract Opacity of lens caused by:  Disease  Injury  Chemicals  Exposure to UV rays Must be removed to prevent blindness  Anterior capsule removed  Phacoemulsification

28. Glaucoma Increased pressure within eyeball More aqueous humor produced than can be drained away Leads to blindness Many causes Screening at routine eye exams Treatment  Medication  Surgery

40. Integumentary system: THE SKIN, NAILS, & HAIR