1. General sensation Composed of sensory receptors throughout the body. –General senses Touch, pressure, pain, heat, cold, stretch, vibration. –Special senses Vision, hearing, equilibrium, olfaction, taste. Relative to the source of the stimuli. –Exteroceptors –Interoceptors –Propioceptors (sketetal muscle). Conscious. General structure (histology, activity 1) –Modified dendrites. Free nerve endings Merkel discs in epidermis Hair follicle receptors Meissner corpuscles: light touch Ruffini corpuscles: deep pressure and stretching. Pacinian corpuscles: pressure recptor. Muscle spindles Golgi tendon organs Receptor physiology –Act as signal transducers. Direct relationship between importance and number of clustering of the receptors; punctuate distribution.

2. Special Senses 1.Vision 2.Olfaction 3.Taste 4.Hearing and equilibrium

3. 1. Vision Organ: Eye ball Accessory structures –Lacrimal apparatus. Lacrimal gland: secretes tears; solution of salts and lyzozyme. Lacrimal canals Nasolacrimal canal –Eyelids (papebrae) –Medial and lateral canthus –Caruncle –Conjunctiva. Mucus membrane that lines inner surface of eyelids. Stratified squamous and stratified cilindrical epithelium. –Eyelashes –Ciliary glands: lubricate eyeball –Tarsal glands: lubricate eyeball –6 extrinsic eye muscles Activity 1

4. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. The eye and associated accessory structures (a) Eyelashes Sclera (covered by conjunctiva) Site where conjunctiva merges with cornea Lateral commissure (canthus) Iris Medial commissure (canthus) Lacrimal caruncle Eyelid Eyebrow Pupil Palpebral fissure

5. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. The lacrimal apparatus Lacrimal sacLacrimal gland Excretory ducts of lacrimal gland Lacrimal punctum Lacrimal canaliculus Nasolacrimal duct Inferior meatus of nasal cavity Nostril

6. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. The eye and associated accessory structures (b) Levator palpebrae superioris muscle Orbicularis oculi muscle Eyebrow Tarsal plate Palpebral conjunctiva Tarsal glands Cornea Palpebral fissure Eyelashes Bulbar conjunctiva Conjunctival sac Orbicularis oculi muscle

7. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Extrinsic eye muscles (a) (b) (c) Optic nerve Inferior rectus muscle Inferior oblique muscle Superior oblique muscle Annular ring Trochlea Superior oblique tendon Superior rectus muscle Lateral rectus muscle Conjunctiva Axis at center of eye Medial rectus muscle Inferior rectus muscle Lateral rectus muscle Lateral rectus Medial rectus Superior rectus Inferior rectus Inferior oblique Superior oblique NameAction Moves eye laterally Moves eye medially Elevates eye and turns it medially Depresses eye and turns it medially Elevates eye and turns it laterally Depresses eye and turns it laterally VI (abducens) III (oculomotor) IV (trochlear) Controlling cranial nerve

8. Internal structure of the eye Composed of 3 layers or tunics –External Cornea (transparent) and Sclera (white). –Middle Anterior –Iris: radial smooth muscle (III ocoulomotor) –Uvea: vasculariazed. –Cilliar body(muscles) : control the curvature of the lens (cristaline). –Cilliary processes: secrete aqueous humor. Posterior –Choroid: dark pigment. –Inner Retina: sensory region Additional internal structures –Humor vitreous –Macula lutea (yellow spot): high cone density –Fovea centralis: area of maximum (very high amount of cones) sight acuity. –Sclera venous sins( Schlemm canal) –Ciliary zonule Activity 2 (eye dissection next class)

9. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Internal structure of the eye (sagittal section) (a) Ora serrata Ciliary body Ciliary zonule (suspensory ligament) Cornea Iris Anterior pole Pupil Anterior segment (cavity) Lens Scleral venous sinus (Canal of Schlemm) Posterior segment (cavity) (contains vitreous humor) Optic nerve Posterior pole Fovea centralis Macula lutea Retina Choroid Sclera Central artery and vein of the retina Optic disc (blind spot)

11. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Circulation of aqueous humor Sclera Bulbar conjunctiva Anterior ciliary vein Scleral venous sinus Posterior chamber Anterior chamber Anterior segment Limbus (corneal- scleral junction) Cornea Corneal epithelium Corneal endothelium Aqueous humor Iris Lens epithelium Lens Posterior segment containing vitreous humor Ciliary zonule (suspensory ligament) Ciliary processes Ciliary muscle Ciliary body ANTERIOR

12. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Focusing for distant and close vision (a) Lens is flattened for distant vision (b) Lens bulges for close vision (c) Anterior segment viewed from behind Lens Inverted image Ciliary zonule Ciliary muscle Nearly parallel rays from distant object Sympathetic + Divergent rays from close object Inverted image Parasympathetic + Ciliary muscle Lens Ciliary zonule (suspensory ligaments)

13. Histology of the retina Sensory tunic –Outer pigmented epithelial layer –Inner neural layer. Photoreceptors: cones or rods. Bipolar neurons Ganglion Axons of ganglions Activity 3

16. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Photoreceptors of the retina Process of bipolar cell Outer fiber Apical microvillus Discs containing visual pigments Inner segment Melanin granules Pigment cell nucleus Inner fibers Rod cell body Cone cell body Synaptic terminals Rod cell body Nuclei Mitochondria Connecting cilia Outer segment Pigmented layer Basal lamina (border with choroid) Retinal Opsin Discs being phagocytized (a) (b) Light

17. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Visual fields of the eyes and visual pathway to the brain, inferior view (a)(b) Pretectal nucleus Right eyeLeft eye Fixation point Optic radiation Superior colliculus (sectioned) Lateral geniculate body Optic tract Optic chiasma Uncrossed (ipsilateral) fiber Crossed (contralateral) fiber Optic nerve Lateral geniculate body of thalamus Superior colliculus Occipital lobe (visual cortex) Corpus callosum Supra- chiasmatic nucleus

18. 2. Olfaction Sensory structure: –Olfactory epithelium. Chemoreceptor. Olfactory receptor cell: bipolar neuron (I) Support cells: pseudo stratified ciliated epithelium. Basal cells. Activity 1

19. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Olfactory receptors Mitral cell Olfactory gland Olfactory tract Olfactory epithelium Filaments of olfactory nerve Cribriform plate of ethmoid bone Lamina propria connective tissue Basal cell Supporting cell Dendrite Olfactory cilia Glomeruli Axon Olfactory receptor cell Mucus Route of inhaled air containing odor molecules Frontal lobe of cerebrum Nasal conchae Route of inhaled air Olfactory epithelium Olfactory tract Olfactory bulb

20. Red: support cell Blue:bipolar neuron Green:basal cell Green:Bowman’s gland cell

21. 3. Taste Sensory structure –Taste bud. Chemoreceptor. Mechanoreceptor. Thermo receptor. Basic tastes: sweet, sour, salt, bitter. Types (location in figure) –Fungiform papillae (mushrooms) –Circunvallate papilla (globes) –Filiform papilla Cell types –Gustatory (taste) cells: bipolar neurons. –Support cells Activity 2

22. Fg: fungiform papillae Fl: filliform papillae Weather’s Fucntional Histology

23. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. (a) (b) (c) (d) Fungiform papillae Taste bud Circumvallate papilla Epiglottis Palatine tonsil Foliate papillae Lingual tonsilBasal cell Taste fibers of cranial nerve Connective tissue Gustatory receptor cells Taste pore Gustatory hair Stratified squamous epithelium of tongue Gustatory (taste) cells Taste pore Connective tissue Basal cells Location and structure of taste buds on the tongue

24. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. The gustatory pathway Gustatory cortex (in insula) Thalamic nucleus (ventral posterior medial nucleus) Pons Solitary nucleus in medulla oblongata Facial nerve (VII) Glosso- pharyngeal nerve (IX) Vagus (nerve X)

25. 4. Hearing and balance Organ: Ear (sensory receptor for hearing and equilibrium). –Outer ear. Hearing Auricle External acoustic meatus Tympanic membrane Ceruminous glands –Middle ear. Hearing Tympanic cavity –Osicles »Malleus (hammer) »Incus (anvil) »Staples (stirrup). Connects with the oval window. Pharingotimpanic tube. Pressure equalization of middle ear and environment. –Inner ear Bony and membranous labyrinth –Cochlea: hearing –Vestible: equilibrium –3 perpendicular semicircular canals: equilibrium

26. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Structure of the ear (a) External (outer) ear Middle ear Internal (inner) ear (labryinth) Pharyngotympanic (auditory) tube External acoustic meatus Auricle (pinna) Helix Lobule Tympanic membrane

27. Middle ear Middle ear. Hearing –Tympanic cavity Osicles –Malleus (hammer) –Incus (anvil) –Staples (stirrup). Connects with the oval window. Pharingotimpanic tube. Pressure equalization of middle ear and environment.

28. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Structure of the middle ear (b) Pharyngotympanic (auditory) tube Auditory ossicles Entrance to mastoid antrum in the epitympanic recess Tympanic membrane Semicircular canals Cochlea Cochlear nerve Vestibular nerve Oval window (deep to stapes) Round window Incus (anvil) Malleus (hammer) Stapes (stirrup) Internal jugular vein Vestibule External acoustic meatus

29. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. The three auditory ossicles in the right middle ear Pharyngotym- panic tube Tensor tympani muscle Tympanic membrane (medial view) Stapes Malleus Superior Anterior IncusEpitympanic recess Stapedius muscle

30. Inner ear –Bony labyrinth Contains perilymph; similar composition to CSF since it is connected to the arachnoid space. –Membranous labyrinth Suspended in perilymph, contains endolymph. Divisions: –Cochlea: organ of Corti, hearing VIII. –Vestible: »utricle and sacule. Macula; vertcial acceleration (equilibrium). –3 perpendicular semicircular canals »Semicircular duct. Ampula; angular acceleration (equilibrium).

31. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Anterior Semicircular ducts in semicircular canals: Posterior Lateral Cristae ampullares in the ampullae Utricle in vestibule Saccule in vestibule Stapes in oval window Temporal bone Facial nerve Vestibular nerve Superior vestibular ganglion Inferior vestibular ganglion Cochlear nerve Maculae Spiral organ (of Corti) Cochlear duct in cochlea Round window Membranous labyrinth of the internal ear

32. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Anatomy of the cochlea (a) Oval window Round window Helicotrema Modiolus Cochlear nerve, division of the vestibulocochlear nerve (VIII) Cochlear duct (scala media) Spiral ganglion Osseous spiral lamina Vestibular membrane

33. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Anatomy of the cochlea (b) Cochlear duct (scala media) Tectorial membrane Vestibular membrane Scala vestibuli Scala tympani Basilar membrane Spiral organ (of Corti) Stria vascularis Spiral ganglion Osseous spiral lamina

34. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Anatomy of the cochlea (c) Tectorial membrane Inner hair cell Outer hair cells Hairs (stereocilia) Afferent nerve fibers Basilar membrane Fibers of cochlear nerve Supporting cells

36. Hearing physiology Sound waves travel from the outer ear (timpanic membrane)  middle ear (Malleus,Incus, staples, oval window)  inner ear (scala tympani)/scala vestibuli  stimulates the stereocillia of the organ of corti  VIII The round window serves as a pressure relief valve.

37. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Sound: source and propagation (a)(b) (c) Area of compressed molecules Crest Trough TimeAmplitude Area of rarefaction Wavelength Air pressure

38. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Route of sound waves through the ear Fluids in cochlear canals Upper and middle Internal earExternal ear Pinna External acoustic meatus Air Tympanic membrane Malleus, incus, stapes (ossicles) Oval window Lower Middle ear One vibration Time Spiral organ (of Corti) stimulated Amplification in middle ear Amplitude Pressure

39. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Resonance of the basilar membrane and activation of the cochlear hair cells (a) (b) (c) Stapes Oval window Scala vestibuli Cochlear duct Scala tympani Basilar membrane Round window Base Hz 20,000 (High notes) Hz 1500 Hz 500 500 Hz 4000 Hz 24,000 Hz Hz 20 (Low notes) Apex Perilymph Cochlear nerve Relative lengths of basilar fibers within different regions of basilar membrane Basilar membrane

40. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Simplified diagram of the auditory pathway to the auditory cortex of the brain Medial geniculate body of thalamus Primary auditory cortex in temporal lobe Inferior colliculus Lateral lemniscus Superior olivary nucleus (pons- medulla junction) Spiral organ (of Corti) Bipolar cell Spiral ganglion of cochlear nerve Vestibulocochlear nerve Medulla Midbrain Cochlear nuclei Vibrations

41. Equilibrium physiology Located in the vestibular apparatus –Vestible Utricle and saccule (sacs) within vesitble. –Receptor: Macculae (static equilibrium) »Hair cells (stereocillia) are embedded in the otholitic membrane which contain CaCO 3 (otoliths). Respond to vertical acceleration. –Membranous semicircular ducts Ampulla (located at the base of each perpendicular duct). Mechism of dynamic equilibrium (angular acceleration). –Receptor: Crista ampullaris. Stereocilia covered by a gelatinous cupula. Endolymph stimulates the recptor.

42. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Structure of a macula Macula of utricle Macula of saccule Otoliths Hair bundle Kinocilium Stereocilia Otolithic membrane Vestibular nerve fibers Hair cells Supporting cells

43. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. The effect of gravitational pull on a macula receptor cell in the utricle Otolithic membrane Kinocilium Stereocilia Receptor potential Nerve impulses generated in vestibular fiber Depolarization (Hairs bent towar kinocilium) d Hyperpolarization (Hairs bent away from kinocilium) Increased impulse frequency Excitation Decreased impulse frequency Inhibition

44. Macula within the utriculus (otolith chamber) (Bouins, H&E, Bar = 36.4 µm). 1. ciliated sensory cells; 2. sustenticular cells; 3. connective tissue; 4. cupula (gelatinous matrix); 5. globular sensory epithelium; 6. collagenous connective tissue; 7. otolith chamber; 8. cranium.

45. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Location and sturcture of a crista ampullaris (a) (c) (d) (b) Cupula Cupula at rest Position of cupula during turn Turning motion Fluid motion in ducts Afferent fibers of vestibular nerve Increased firingDecreased firing Position of cupula during turn Ampulla of left ear Ampulla of right ear Horizontal ducts Flow of endolymph Cupula Crista ampullaris Fibers of vestibular nerve

47. Human Anatomy and Physiology, 7e by Elaine Marieb & Katja Hoehn Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Pathways of the balance and orientation system Input Central nervous system processing Output Oculomotor control (cranial nerve nuclei III, IV, VI) (eye movements) Spinal motor control (cranial nerve nuclei XI and vestibulospinal tracts) (neck movements) Vestibular receptors Visual receptors Cerebellum Vestibular nuclear complex Reticular nuclei Somatic receptors