1. Anatomy & Physiology I The Senses Seminar 8

2. Unit 8 – Senses Overview Classification of Sense Organs General Free Nerve Endings Encapsulated Nerve Endings Special Eye Ear Taste Receptors Smell Receptors Structures of Each

3. Classification of the Sense Organs General sense organs  Often exist as individual cells or receptor units  Widely distributed throughout the body Special sense organs  Large and complex organs  Localized grouping of specialized receptors Classified by presence or absence of covering capsule  Encapsulated  Unencapsulated (“free” or “naked”)

4. Classification made by type of stimuli required to activate receptors  Photoreceptors (light)  Chemoreceptors (chemicals)  Pain receptors (injury)  Thermoreceptors (temperature changes)  Mechanoreceptors (movement or deforming of capsule)  Proprioceptors (position of body parts or changes in muscle length or tension) Classification of the Sense Organs (cont’d.)

5. Converting a Stimulus into a Sensation All sense organs have common functional characteristics  All are able to detect a particular stimulus  A stimulus is converted into a nerve impulse  A nerve is perceived as a sensation in the CNS

6. General Sense Organs Distribution is widespread; single-cell receptors are common Examples  Free nerve endings: Sensitive to pain and crude touch  Meissner corpuscles: Responsive to fine touch and vibration  Ruffini corpuscles: Sensitive to touch and pressure  Krause’s end-bulbs: Touch or cold  Golgi tendon receptors: Proprioception  Muscle spindles: Proprioception

7. General Sense Receptors

8. Special Sense Organs Four types Eyes Ears Nose Taste Buds Let’s take a look at each one….

9. Special Sense Organs The Eye Function Structure Three layers of the eyeball Sclera Choroid Retina

10. Special Sense Organs (cont’d.)  Conjunctiva:  Mucous membrane covering the front surface of the sclera and lining the eyelid  Lens:  Transparent body behind the pupil; focuses light rays on the retina  Eye fluids  Aqueous humor  Watery fluid in the anterior chamber in front of the lens  Vitreous humor  Jellylike fluid in the posterior chamber behind the lens

11. FYI on the Iris As the fibers of the iris contract, the pupils dilate, letting in more light. Other fibers are circular. When they contract, the pupils constrict, letting in fewer light rays. Normally the pupils constrict in bright light and dilate in dim light.

12. The Eye - Structure

13. Special Sense Organs (cont’d) Visual Pathway Innermost layer of retina contains rods and cones Impulse travels from the rods and cones through the bipolar and ganglionic layers of the retina Nerve impulse leaves the eye through the optic nerve; the point of exit is free of receptors and is therefore called a blind spot.

14. Cells of the Retina

15. Conditions & Surgery for the Eye Conditions Presbyopia Cataracts Blind Spot Glaucoma Take a look at these surgical procedures on your own…. Radial keratotomy (RK) Astigmatic Keratotomy (AK) Automated Lamellar Keratoplasty (ALK) Laser Assisted in situ Keratomileusis (LASIK) Conductive Keratoplasty (CK)

16. Corneal Transplant

17. Special Sense Organs (cont’d) The Ear Function  The ear functions in hearing, equilibrium, and balance.  Receptors for hearing and equilibrium are mechanoreceptors.  Structure  External Ear  Middle Ear  Inner Ear

18. The Ear

19. Special Sense Organs (cont’d)  Structure – Divisions of the Ear  External ear o Auricle (pinna) o External auditory canal Curving canal or tube 2.5 cm (1 inch) in length Contains ceruminous glands producing ear wax Ends at the tympanic membrane or eardrum

20. Special Sense Organs (cont’d)  Middle ear o Houses ear bones or ossicles o malleus, incus, and stapes o Ends in the oval window o The auditory (eustachian) tube connects the middle ear to the throat o Inflammation called “otitis media”

21. Special Sense Organs (cont’d)  Inner ear o The bony labyrinth is filled with fluid called perilymph o The labyrinth is divided into the vestibule, semicircular canals, and cochlea o Membranous labyrinth is filled with endolymph o Receptors for balance in the semicircular canals are called cristae ampullaris o Specialized hair cells on the organ of Corti respond when bent by the movement of surrounding endolymph set in motion by sound waves

22. Inner Ear

23. Sound Waves

24. Special Sense Organs (cont’d.) The Taste Receptors  Receptors are Chemoreceptors called taste buds  Cranial nerves VII and IX carry gustatory impulses  Six kinds of “primary” taste sensations—sweet, sour, bitter, salty, metallic, and umami (meaty)  Gustatory and olfactory senses work together

25. The Tongue

26. Special Sense Organs (cont’d.) The Olfactory (smell) Receptors  Receptors for fibers of olfactory or cranial nerve lie in olfactory mucosa of nasal cavity  Olfactory receptors are extremely sensitive but easily fatigued  Odor-causing chemicals initiate a nervous signal that is interpreted as a specific odor by the brain

27. Olfactory Structures

28. Let’s Review! Unit 8 Chapter 9

29. Which of these is a special sense? A. Pressure B. Stretch C. Vision D. Temperature E. Pain

30. A mechanoreceptor may detect changes in__________? A. Temperature B. Light intensity C. pH D. Pressure E. Presence of sugars

31. Muscle spindles are involved in the sense of _______________? A. Proprioception B. Pain C. Smell D. Movement E. Gravity

32. Most of the functional part of the ear lies deep within the: A. Parietal bone B. Frontal bone C. Occipital bone D. Temporal bone

33. What are the names of the three ossicles that allow sound to be transmitted through the middle ear? : 1. Malleus, Incus, Stapes 2. Cochlear nerve, Auditory tube, Oval window 3. Ampulla, Vestibule, Semicircular Canals 4. Endolymph, Perilymph, Acoustic nerve

34. The layers of the eyeball are all except? A. Sclera B. Choroid C. Retina D. Cochlea

35. Which Division of the Ear is being described below? The semicircular canals are filled with endolymph and are the primary organs in maintaining balance and equilibrium. Damage or disease to this part of the ear not only affects balance but also may result in permanent hearing loss.

36. The transparent window of the eye is? 1. Retina 2. Iris 3. Cornea 4. Choroid 5. None of the above

37. The colored muscular part of the eye? A. Iris B. Retina C. Sclera D. pupil

38. The gland that produces tears is? A. Endocrine B. Lacrimal C. Pituitary D. Salivary E. None of the above

39. What is being described below? Sense Sweet, Sour, Salty, Bitter tastes The medical term for taste buds Papillae Part of the tongue

40. Nearsightedness is: A. Myopia B. Astigmatism C. Presbyopia D. Glaucoma E. hyperopia

41. Which photoreceptor is responsible for Color vision? A. Rods B. Cones

42. The organ of Corti is involved in the sense of____? A. Vision B. Pain C. Hearing D. Equilibrium E. Motion

43. Sensory perception occurs in the_____? A. Receptor B. Organ surrounding the receptor C. Afferent neuron D. Brain

44. When a person ages, the lenses of the eye lose some of their elasticity and can no longer bring near objects into focus. This is called: A. Hyperopia B. Myopia C. Astigmatism D. presbyopia

45. Visual interpretation occurs in: A. The cerebellum B. The pons C. The medulla oblongata D. The cerebrum

46. When the lens becomes hard, loses its transparency and becomes cloudy: A. Glaucoma B. Myopia C. Retinopathy D. Cataracts E. astigmatism

47. Inflammation of the middle ear: A. Otitis externa B. Otitis interna C. Otitis media

48. Question to ponder…. We have discussed the importance of maintaining homeostasis in our bodies. We have seen how the integumentary system and muscular system contribute to homeostasis. How would you suggest that the general and special senses contribute to homeostasis?

49. Answer The general and special senses help maintain homeostasis in the body by monitoring the conditions in our environment. For instance, heat and cold receptors help us to avoid conditions that will adversely affect temperature regulation in our body. Pain receptors tell us to avoid touching certain things. Because of special senses such as sight and hearing, we are able to avoid many dangerous situations, which helps maintain conditions within a normal range in the body. Our general and special senses are constantly accumulating data that are integrated with memory and reflexes to produce homeostatic responses

50. Review of Final Project  You are tasked with creating a PowerPoint presentation that will be used to educate a patient on a recently diagnosed condition.  Create an educational and informative piece that can be understood by the average citizen.  Details: 1. Select a disease or condition that has been covered in one of the systems discussed in this course (Chapters 1-10). 2. Describe the anatomy of the organs, physiology, pathology, and biochemistry involved in the diagnosis. 3. Include information about how other organ systems are impacted by the condition.

51. What you are required to include…. Be sure that you have addressed the following objectives in your work: Identify the major anatomical regions, landmarks, directions and cavities of the organs affected by the diagnosis. Identify the organs involved in the diagnosis. Explain the normal functioning of the organs. Analyze the chemical basis of physiologic processes involved in the disease. Explain how the disease or condition affects the integration of the body systems in maintaining homeostasis. Describe the functional relationships between the body systems and the disease process.

52. An APA PowerPoint Title slide - Includes the same information as an APA paper. Introduction slide– a bulleted slide that covers the major points you will be covering in the PPT Slides Titles for each slide No more than 5 – 7 words for each bulleted item If you include pictures on the slide, you have to place a caption under the picture that includes the citation in order to avoid copyright issues. 12 – 15 Slides (not including your title or reference slide) Speaker notes This is where you will explain the bulleted items on your slide. Cite your references in proper APA format – No URLs Conclusion slide– sum up your work Reference slide (see next slide)

53. References Do not use a website address as the reference Use a hanging indent Use proper APA reference format for each type of material you use. Journal article Website Textbook Other….

54. Proper Reference for our Textbook  References  Textbook Reference Thibodeau, G., Patton, K. (2008). Structure and Function of the Body 9 (13 th ed). St. Louis, MO: Mosby Elsevier Publishing Notice the second line is indented 0.5” This is called a hanging indent

55. Website Examples for Citations and the corresponding References In-text Citation example (speaker notes): The National Osteoporosis Foundation (2004) stated, “Eighty persons of those affected by osteoporosis are women” (¶ 1). Multiple Sclerosis affects more women than men (Copeland, 2003). References (this is what your reference page would look like) National Osteoporosis Foundation. (2004). Fast facts. Retrieved from http://www.nof.org Copeland, L. (2003). Managing Multiple Sclerosis. Journal of Neurological Disorders, 25, 69 – 72. Retrieved from http://www.jobjournal.com

56. Reminder of My favorite quote…..  Don’t wait until the final day to ask for help.  Favorite saying….  Lack of planning on your part, does not constitute an emergency on my part.  Yes, you can borrow this for your older children, coworkers and anyone else who meets the criteria!

57. Reminders & Questions Surveys Important to new students learning Quality Improvement Week 9 is our last Seminar No seminar in Week 10 Final Exam in Week 10 and reflective discussion Final Project is Due at the end of Unit 9 Don’t wait until the last minute Please review for any last minute questions this weekend Send email with questions QUESTIONS?