Seeley's Essentials of Anatomy & Physiology Eleventh Edition Chapter 9 Senses Lecture Outline PDF

Because learning changes everything.® Chapter 9 Senses Lecture Outline Seeley’s ESSENTIALS OF ANATOMY & PHYSIOLOGY Eleventh Edition Cinnamon VanPutte Jennifer Regan Andrew Russo Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written c...

Because learning changes everything.® Chapter 9 Senses Lecture Outline Seeley’s ESSENTIALS OF ANATOMY & PHYSIOLOGY Eleventh Edition Cinnamon VanPutte Jennifer Regan Andrew Russo Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. Senses Sense: ability to perceive stimuli Sensation: conscious awareness of stimuli received by sensory neurons Sensory receptors: sensory nerve endings that respond to stimuli by developing action potentials Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 2 Classification of Senses Figure 9.1 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 3 Types of Senses General senses: receptors over large part of body that sense touch, pressure, pain, temperature, and itch somatic senses provide information about body and environment visceral senses provide information about internal organs Special senses: smell, taste, sight, hearing, and balance Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 4 Types of Receptors 1 Mechanoreceptors: detect movement Example, touch, pressure, vibration Chemoreceptors: detect chemicals Examples, odors and taste Photoreceptors: detect light Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 5 Types of Receptors 2 Thermoreceptors: detect temperature changes Nociceptors: detect pain Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 6 Types of Touch Receptors 1 Merkel’s disk: detect light touch and pressure Hair follicle receptors: detect light touch Meissner corpuscle: deep in epidermis localizing tactile sensations Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 7 Types of Touch Receptors 2 Ruffini corpuscle: deep tactile receptors detects continuous pressure in skin Pacinian corpuscle: deepest receptors associated with tendons and joints detect deep pressure, vibration, position Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 8 Sensory Receptors in the Skin Figure 9.2 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 9 Pain Pain is an unpleasant perceptual and emotional experience Pain can be localized or diffuse. Localized: sharp, pricking, cutting pain rapid action potential Diffuse: burning, aching pain slower action potentials Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 10 Pain Control Local anesthesia: action potentials suppressed from pain receptors in local areas chemicals are injected near sensory nerve General anesthesia: loss of consciousness chemicals affect reticular formation Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 11 Referred Pain Originates in a region that is not source of pain stimulus Felt when internal organs are damaged or inflamed Sensory neurons from superficial area and neurons of source pain converge onto same ascending neurons of spinal cord Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 12 Areas of Referred Pain Figure 9.3 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 13 Olfaction Olfaction is the: sense of smell occurs in response to odorants receptors are located in superior portion of the nasal cavity we can detect 10,000 different smells Figure 9.4a Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 14 Olfaction Process 1. Nasal cavity contains a thin film of mucous where odors become dissolved. 2. Olfactory neurons are located in the mucous. Dendrites of olfactory neurons are enlarged and contain cilia. 3. Dendrites pick up odor, depolarize, and carry odor to axons in olfactory bulb (cranial nerve I). 4. Frontal and temporal lobes process odor. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 15 Olfactory Epithelium and Olfactory Bulb Figure 9.4b Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 16 Taste Taste buds: sensory structures that detect taste located on papillae on tongue, hard palate, throat Inside each taste bud are 40 taste cells Each taste cell has taste hairs that extend into taste pores Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 17 The Tongue Figure 9.5 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 18 Taste Process 1. Taste buds contain about 40 taste cells. 2. Taste cells send taste stimuli to taste hairs. 3. Taste cells contain hairlike processes, called taste hairs, that extend through a taste pore to the surface of the taste bud. 4. Dissolved molecules or ions bind to receptors on the taste hairs and initiate action potentials. Sensory neurons carry signals to the insula of the cerebral cortex. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 19 Types of Tastes 1. Sweet 2. Sour 3. Salty 4. Bitter 5. Umami Certain taste buds are more sensitive to certain tastes. Taste is also linked to smell. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 20 Pathways for the Sense of Taste Figure 9.6 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 21 Vision Accessory Structures Eyebrow: protects from sweat shade from sun Eyelid/Eyelashes: protects from foreign objects lubricates by blinking Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 22 The Eye and Accessory Structures 1 (a) ©Eric Wise Figure 9.7a Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 23 The Eye and Accessory Structures 2 Conjunctiva: thin membrane that covers inner surface of eyelid Lacrimal apparatus: produces tears Extrinsic eye muscles: help move eyeball Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 24 Lacrimal Gland Structures Figure 9.7c Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 25 Extrinsic Eye Muscles Figure 9.8 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 26 Anatomy of Eye Hollow, fluid filled sphere Composed of 3 layers (tunics) Divided into chambers Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 27 The Eye Figure 9.9 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 28 Fibrous Tunic Outermost Tunic Sclera: firm, white outer part helps maintain eye shape, provides attachment sites for muscles, protects internal structures Cornea: transparent structure that covers iris and pupil allows light to enter and focuses light Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 29 Vascular Tunic 1 Middle tunic Contains blood supply Choroid: black part (melanin) delivers O2 and nutrients to retina Ciliary body: helps hold lens in place Ciliary muscle: Controls shape of lens via suspensory ligaments Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 30 Vascular Tunic 2 Suspensory ligaments: help hold lens in place Lens: flexible disk focuses light onto retina Iris: colored part of eye surrounds and regulates pupil Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 31 Vascular Tunic 3 Pupil: regulates amount of light entering lots of light = constricted little light = dilated Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 32 Lens and Ciliary Body Figure 9.10b Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 33 The Iris Figure 9.10c Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 34 Nervous Tunic 1 Innermost tunic Retina: covers posterior 5/6 of eye contains 2 layers Pigmented retina: outer layer keeps light from reflecting back in eye Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 35 Nervous Tunic 2 Sensory retina: contains photoreceptors (rods and cones) contains interneurons Rods: photoreceptor sensitive to light 20 times more rods than cones can function in dim light Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 36 Nervous Tunic 3 Cones: photoreceptor provide color vision 3 types blue, green, red Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 37 The Retina 1 Rods and cones synapse with bipolar cells of sensory retina Horizontal cells of retina modify output of rods and cones Bipolar and horizontal cells synapse with ganglion cells Ganglion cell’s axons converge to form optic nerve Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 38 The Retina 2 Figure 9.11 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 39 The Retina 3 Macula: small spot near center of retina Fovea centralis: center of macula where light is focused when looking directly at an object only cones ability to discriminate fine images Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 40 The Retina 4 Optic disk: white spot medial to macula blood vessels enter eye and spread over retina axons exit as optic nerve no photoreceptors called blind spot Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 41 The Retina 5 (a) Steve Allen/Getty Images RF Figure 9.12 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 42 Chambers of the Eye 1 Anterior chamber: located between cornea and lens filled with aqueous humor (watery) aqueous humor helps maintain pressure, refracts light, and provide nutrients to inner surface of eye Posterior chamber: located behind anterior chamber contains aqueous humor Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 43 Chambers of the Eye 2 Vitreous chamber: located in retina region filled with vitreous humor: jelly-like substance vitreous humor helps maintain pressure, holds lens and retina in place, refracts light Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 44 Functions of the Eye 1 The eye functions much like a camera. The iris allows light into the eye through the pupil, which is focused by the cornea, lens, and humors onto the retina. The light striking the retina produces action potentials that are relayed to the brain. Light refraction and image focusing are two important processes in establishing vision. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 45 Functions of the Eye 2 Light Refraction Bending of light Focal point: point where light rays converge occurs anterior to retina object is inverted Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 46 Functions of the Eye 3 Focusing Images on Retina Accommodation: Changes in shape of the lens so image can be focused on retina enables eye to focus on images closer than 20 feet Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 47 Focusing by the Eye Figure 9.14 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 48 Action Potential Generation at the Retina Rhodopsin: photosensitive pigment in rod cells Opsin: colorless protein in rhodopsin Retinal: yellow pigment in rhodopsin requires vitamin A Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 49 Effects of Light on Rhodopsin 1 1. Light strikes rod cell 2. Retinal changes shape 3. Opsin changes shape 4. Retinal dissociates from opsin 5. Change in rhodopsin shape stimulates response in rod cell which results in vision 6. Retinal detaches from opsin 7. ATP required to reattach retinal to opsin and return rhodopsin to original shape Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 50 Photoreceptors Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 51 Effects of Light on Rhodopsin 2 Figure 9.16 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 52 Neuronal Pathway for Vision Optic nerve: leaves eye and exits orbit through optic foramen to enter cranial cavity Optic chiasm: where 2 optic nerves connect Optic tracts: route of ganglion axons Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 53 Visual Pathway 1 Figure 9.18 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 54 Visual Pathway 2 Figure 9.19 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 55 Color Blindness The absence of perception of one or more colors The loss may involve perception of all three colors or of one or two colors. Most forms of color blindness occur more frequently in males and are X-linked genetic traits Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 56 Chart to Determine Color Blindness (a) Steve Allen/Getty Images; (b) Prisma Bildagentur AG/Alamy Stock Photo Figure 9.17 Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 57 The Ear The organs of hearing and balance are located in the ears. Each ear is divided into three areas: 1. the external ear 2. the middle ear 3. the inner ear Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 58 The External Ear Extends from outside of head to eardrum Auricle: fleshy part on outside External auditory meatus: canal that leads to eardrum Tympanic membrane: eardrum thin membrane that separates external and middle ear Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 59 The Middle Ear 1 Air filled chamber with ossicles Malleus (hammer): bone attached to tympanic membrane Incus (anvil): bone that connects malleus to stapes Stapes (stirrup): bone located at base of oval window Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 60 The Middle Ear 2 Oval window: separates middle and inner ear Eustachian or auditory tube: opens into pharynx equalizes air pressure between outside air and middle ear Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 61 The Inner Ear 1 Set of fluid filled chambers Bony labyrinth: tunnels filled with fluid 3 regions: cochlea, vestibule, semicircular canals Membranous labyrinth: inside bony labyrinth filled with endolymph Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 62 The Inner Ear 2 Endolymph: clear fluid in membranous labyrinth Perilymph: fluid between membranous and bony labyrinth Cochlea: snail-shell shaped structure where hearing takes place Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 63 The Inner Ear 3 Scala vestibuli: in cochlea filled with perilymph Scala tympani: in cochlea filled with perilymph Cochlea duct: in cochlea filled with endolymph Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 64 The Inner Ear 4 Spiral organ: in cochlear duct contains hair cells Tectorial membrane: in cochlea vibrates against hair cells Hair cells: attached to sensory neurons that when bent produce an action potential Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 65 The Inner Ear 5 Vestibular membrane: wall of membranous labyrinth that lines scala vestibuli Basilar membrane: wall of membranous labyrinth that lines scala tympani Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 66 Structure of the Ear Figure 9.20 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 67 Structure of the Inner Ear (e) Courtesy of A. J. Hudspeth Figure 9.21 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 68 Hearing Process 1 1. Sound travels in waves through air and is funneled into ear by auricle. 2. Sound travels through external auditory meatus to tympanic membrane. 3. Tympanic membrane vibrates and sound is amplified by malleus, incus, stapes which transmit sound to oval window. 4. Oval window produces waves in perilymph of cochlea. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 69 Hearing Process 2 5. Vibrations of perilymph cause vestibular membrane and endolymph to vibrate. 6. Endolymph vibrations cause displacement of basilar membrane. 7. Movement of basilar membrane is detected by hair hairs in spiral organ. 8. Hair cells become bent and cause action potentials to be created. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 70 Effect of Sound Waves on Middle and Inner Ear Structures Figure 9.22 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 71 Balance (Equilibrium) Static equilibrium: associated with vestibule evaluates position of head relative to gravity Dynamic equilibrium: associated with semicircular canals evaluates changes in direction and rate of head movement Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 72 Balance 1 Vestibule: inner ear contains utricle and saccule Maculae: specialized patches of epithelium in utricle and saccule surround by endolymph contain hair cells Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 73 Balance 2 Otoliths: Particles of protein and calcium carbonate embedded in a gelatinous substance that moves in response to gravity Microvilli of hair cells are embedded in the gelatinous substance and initiate action potentials when bent Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 74 Location and Structure of the Macula Figure 9.24 (d) Susumu Nishinag/Science Source Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 75 Function of the Vestibule in Maintaining Balance (a, b) ©Trent Stephens Figure 9.25 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 76 Balance 3 Semicircular canals: dynamic equilibrium sense head movement in any direction Ampulla: Swelling at base of semicircular canal Crista ampullaris: in ampulla Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 77 Balance 4 Cupula: gelatinous mass contains microvilli of hair cells float that is displaced by endolymph movement Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 78 Semicircular Canals Figure 9.26 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 79 Function of the Crista Ampullaris (a) Julie Jacobson/AP Images Figure 9.27 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 80