1. Week #6 (2/8 – 2/12) Warm Up – Mon, 2/8: -Special Senses Latin Cards Have out:  Index Cards Pick up:  1 colored marker  6 index cards & a scissors  Diagram of the Eye Agenda: 1.Special Senses Latin cards 2.Begin Special Senses - Eye Anatomy Fun Fact: In 1 min, the brain will consume 46 cm 3 (1/5 cup) of oxygen from blood. Of that oxygen consumed, 6% will be used by the brain's white matter & 94% by the grey matter. The brain can stay alive for 4-6 mins without oxygen; after that cells begin die. Homework: 1.Special Senses Latin Cards – Tues, 2/9 2.Brain/Spinal Cord Dissection Abstract (1D) – Wed, 2/10 & Thurs, 2/11

2. Nervous System (Special Senses) Latin Roots Photo – light Recepto- – receive Conjunctiva – connective Lacrima – tear, weeping Vascu – made of vessels Sclera – outermost coat of eye Cornea – resembling a horn in hardness & appearance Choroid – skin-like Retina – interior, light-detecting coat of eye Humor – fluid, liquid Vitreo – glass-like, glaze Aque/a – water Iris – rainbow Glauc(o) – bluish-gray color -oma – tumor Audire – to hear Auri – ear Helix – spiral Tympani – small drum Oss – bone Malleus – hammer, mallet Incus – anvil Stapes – stirrup Vestibul(um/i) – entrance Semi – half Cochlea – snail shell-shape, spiral in shape

3. Taste, Smell, Sight, Hearing (we’re just going to focus on “Sight & Hearing”)

4. Photoreceptors – visual receptor cells Adult eye = ~ 1 in. diameter Accessory structures – protect the eye or aid in its functioning Eyebrows Eyelids Conjunctiva Lacrimal apparatus Extrinsic Eye muscles

5. Eyebrows & Eyelids Eyebrows Shade eyes from sunlight Prevent perspiration from entering eyes Eyelids (palpabrae) Blinking occurs every 3-7 secs to prevent dehydration of eyes Eyelashes are richly innervated, so anything that touches them, including a puff of air, triggers reflex blinking

6. Conjunctiva Transparent mucous membrane that lines eyelids & reflects over surface of eyeball Lubricate eye & to prevent invasion to posterior portion of eye Conjunctivitis is an inflammation of the conjunctiva Pinkeye is a type of conjunctivitis caused by bacteria or virus

7. Lacrimal Apparatus Consists of the lacrimal gland & lacrimal ducts Lacrimal gland releases fluid that is spread over eye when blinking Contains mucus, antibodies & lysozyme (a bacteria-destroying enzyme)

8. Don’t need to know this!

9. Structure of the Eyeball Made up of three layers called tunics Fibrous (1) Vascular (2) Sensory (3) Fibrous tunic is the outermost coat of the eye (1) Divided into 2 major regions: sclera & cornea Sclera (tough connective tissue) - “whites of the eye” Functions to protect & shape eyeball Sturdy anchoring for extrinsic eye muscles 3

10. More on the Eye Cornea - anterior 6 th of fibrous tunic Covered on both sides by simple squamous epithelium Lined with pain fibers (which is why contacts can be so tough to adjust to) When cornea is touched, reflex blinking & increased lacrimal fluid secretion occur FUN FACT: Since cornea has no blood supply it is the only tissue that can be transplanted with very little fear of rejection (does not have contact with immune system)

11. Week #6 (2/8 – 2/12) Warm Up – Tues, 2/9: - Intro to NS Review Pick up:  3 colored pencils  Brain Latin Take- home Quiz Agenda: 1.Finish Eye/Vision notes Anatomy Fun Fact: Results from cognitive tests show 30% of 80- year-olds perform as well as young adults (like YOU!). Homework: 1.Brain/Spinal Cord Dissection Abstract (1D) – Wed, 2/10 & Thurs, 2/11 2.Brain Latin Take- home Quiz – Fri, 2/12 3.Nervous System Exam – Fri, 2/19

12. Iris Most anterior part of vascular tunic (middle layer) (2) Between cornea & lens Round central opening (pupil) allows light to enter eye Made of smooth muscle fibers that contract & dilate depending on light stimulus 3

13. Iris Though it seems to appear in many colors (Iris means “rainbow”), it actually only contains brown pigment When an iris contains a lot of pigment, the eyes appear brown or black If the amount of pigment is small, the short wavelengths of light are scattered from the unpigmented parts of the iris & eyes appear blue, green, or gray Why, then, do newborn babies often appear to have gray or blue eyes?

14. The Sensory Tunic (Retina & Lens) Deepest layer Contains the lens (hard disc) which allows an image that is upside down & backwards Has pigmented cells that absorb light Stores Vitamin A, which is needed by photoreceptor cells Contains millions of photoreceptors Rods & cones Rods - more numerous & are our dim-light & peripheral receptors (more sensitive to light) Cones - bright light & provide high- acuity color vision The optic disc (located where the optic nerve leaves the posterior portion of the eye) is called the “blind spot” because it contains no photoreceptors Lens

15. Internal Chambers Filled with aqueous humor which is produced in posterior chamber & drains from anterior chamber If drainage is blocked, pressure within eye may increase & cause compression of retina & optic nerve condition called glaucoma Exam to diagnose is simple…a puff of air at the sclera will produce a measurable amount of deformation

16. Colorblind & blindspot Tests Colorblindness: http://www.toledo-bend.com/colorblind/Ishihara.html http://colorvisiontesting.com/online%20test.htm#demo nstration%20card http://colorvisiontesting.com/online%20test.htm#demo nstration%20card Blind Spot: http://faculty.washington.edu/chudler/chvision.html

17. Week #6 (2/8 – 2/12) Warm Up – Wed, 2/10 & Thurs,2/11: - Structure of the Eye wkst Turn in:  Brain/Spinal Cord Dissection Abstract (1D) Pick up:  Structure of the Eye wkst Agenda: 1.Cow Eye Dissection 2.Discuss Eye Dissection Lab Abstract Homework: 1.Brain Latin Take- home Quiz – Fri, 2/12 2.Cow Eye Dissection (2D)– Fri, 2/19 3.Nervous System Exam – Fri, 2/19 Anatomy Fun Fact: How does Lasik surgery correct/improve vision? The surgeon uses a small instrument, called a microkeratome, to create an ultra-thin flap in the cornea. After the surgeon has created a flap, they will use an excimer laser to reshape the corneal tissue. It is this reshaping of the cornea that improves your vision, changing the way your eye focuses light.

18. Cow Eye Dissection (2D) Follow the directions CAREFULLY off of the “Cow’s Eye Dissection” packet. On a separate piece of paper (with ALL GROUP MEMBERS’ names), answer the questions in your Nasco Lab Manual (Conclusion & Application section)! Only take enough gloves for those who will be dissecting/holding eye. Make sure to CLEAN & DRY lab stations, kits & trays after you are finished! Have fun!

19. Eye Dissection Lab Abstract (2D) Title Page : Title of Lab, Name, Date, Period Data & Observations : Pictures of Eye (whole & internal structures) w/correct identifications Conclusions & Applications : Answers to ALL questions from Lab Manual (in paragraph form) Discuss the cause(s) of the disease, symptoms, treatments or cures & what structures/regions of the eye are degenerated/damaged due to the disease What is the function of eyelids? Eyelashes? Eyebrows? Of what biological use are tears to the eye? Of what value is the response of pupil dilation & constriction? Describe the function for each of the pairs of muscles that are attached to the eye. What is the relationship of the optic nerve & the brain? What type of muscle orientation in the iris would be necessary to regulate the diameter of the pupil? What is the function of the gelatinous substance known as vitreous humor? Application: Case Study – research & discuss one disease that affects the eye(s) Works Cited (MLA format) DUE: Fri, 2/19

20. Week #6 (2/8 – 2/12) Warm Up – Fri, 2/12: -Sensory Systems Active Reading wkst Turn in:  Brain Latin Quiz Pick up:  Sensory Systems Active Reading wkst  3 colored pencils  Nervous System Review Guide Agenda: 1.Sense of Hearing/Ear notes 2.Work on Nervous System Review Guide (if time) Homework: 1.Cow Eye Dissection (2D) – Fri, 2/19 2.Nervous System Exam – Fri, 2/19 Anatomy Fun Fact: There are over 90% of deaf children born from parents with normal hearing, meaning that a couple with normal hearing has no guarantee that their children will have normal hearing.

21. Divided into 3 major regions: Inner ear Middle ear Outer ear

22. LABEL & COLOR-CODE YOUR WKST Outer EarMiddle EarInner Ear

23. Outer Ear Consists of the auricle & the external auditory canal Auricle helix (rigid portion) lobule (no cartilage) Functions to direct sound waves into external auditory canal External auditory canal Short (~2.5 cm) & curved Extends to the tympanic membrane (“eardrum”)

24. Middle Ear Small, air-filled cavity within the temporal bone Eustachian tube links middle ear to superior-most part of the throat Normally this is closed, but yawning & swallowing opens this tube briefly to equalize pressure

25. Contains the 3 smallest bones in the body: the ossicles Malleus – secured to the tympanic membrane Incus Stapes – connects to the inner ear (via the oval window) Tensor tympani muscle attaches auditory tube (Eustachian tube) to malleus This muscle helps prevent damage to inner ear under extremely loud conditions Middle Ear

26. Inner Ear Located deep within the temporal bone & posterior to the eye socket Made up of the vestibule, semicircular canals & cochlea

27. Vestibule Central egg-shaped cavity that medially borders the middle ear Contains perilymph (similar to CSF) Houses equilibrium censors called maculae that respond to pull of gravity & report changes of head position

28. Semicircular Canals Made up of an anterior, posterior, & lateral canals Have receptors to help with equilibrium

29. Cochlea About 1/2 size of a pea Contains 3 hollow cavities Cochlear duct contains spiral organ of Corti – receptor organ for hearing Cochlear nerve runs from the spiral organ of Corti to the brain

30. Hair Cells in the Spiral Organ of Corti Roughly 16,000 hearing receptor cells called cochlear hair cells line the spiral organ of Corti

31. Sounds set up vibrations in air that beat against the ear drum This pushes the ossicles that press fluid in the inner ear against membranes This pressure on the membranes pulls on tiny hair cells that stimulate nearby neurons that give rise to impulses that travels to the brain, where they are interpreted

32. Deafness 2 types: Conduction Sensorineural Conduction deafness – occurs when something interferes with conduction of sound vibrations to the fluids of the inner ear

33. Deafness 2 types: Conduction Sensorineural Sensorineural deafness – results from damage to neural structures at any point in the hearing pathway This typically results from the gradual loss of hearing receptor cells: Throughout life Single explosively loud noise Prolonged exposure to high-intensity sounds, which cause these cells to stiffen