Special Senses
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The company also empowers educators to engage their students more effectively through customizable books and intuitive teaching tools as part of the Boundless Teaching Platform. More than 2 million learners access Boundless free and premium content each month across the company’s wide distribution platforms, including its website, iOS apps, Kindle books, and iBooks. To get started learning or teaching with Boundless, visit boundless.com. Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) The Vertebrate Visual System Taste and Olfaction Hearing and Equilibrium Development of Special Senses Boundless.com/physiology?campaign_content=book_299 _chapter_15&campaign_term=Physiology&utm_campaign =powerpoint&utm_medium=direct&utm_source=boundless Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) > The Vertebrate Visual System The Vertebrate Visual System • Anatomy of the Eye • Transduction of Light • Visual Processing Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology?campaign_content=book_299_chapter_15&campaign_term=Physiology&utm_campaign=powerpoint&utm_mediu m=direct&utm_source=boundless Special Senses (Vision, Hearing, Taste, and Smell) > The Vertebrate Visual System Anatomy of the Eye • The cornea and the lens bend light to focus the image on the retina; the iris and pupil regulate the amount of light entering the eye. • The aqueous humour maintains the convex shape of the cornea; the vitreous humour supports the lens and maintains the shape of the entire eye. • Presbyopia occurs because the image focuses behind the retina; it is similar to hyperopia (farsightedness), which is caused by an eyeball that is too short. • Myopia (nearsightedness) occurs when an eyeball is elongated; images in the distance appear blurry, but images nearby are clear. • Rods are used for peripheral and nighttime vision; cones are used for daytime Retina View on Boundless.com and color vision. • The fovea is is responsible for acute vision because it has a high density of cones. 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Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell-15/thevertebrate-visual-system-145/anatomy-of-the-eye-760- Special Senses (Vision, Hearing, Taste, and Smell) > The Vertebrate Visual System Transduction of Light • When light hits the photoreceptor, the retinal changes shape, which activates the photopigment rhodoposin. • Primates have full color vision because of the three-cone (trichromatic) system; color is a result of the ratio of activity of the three types of cones. • There are three types of cones with different photopsins: S cones respond to short waves; M cones respond to medium waves; L cones respond to light to long waves. • If light is not present, neurons are inhibited by rods and cones; once light is introduced, rods and cones are hyperpolarized, which activates the neurons. • Activated neurons stimulate ganglion cells, which send action potentials via the Hyperpolarized visual receptors View on Boundless.com optic nerve. • Horizontal cells can create lateral inhibition, which enhances light and dark contrast in images. Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell-15/thevertebrate-visual-system-145/transduction-of-light-761- Special Senses (Vision, Hearing, Taste, and Smell) > The Vertebrate Visual System Visual Processing • The magnocellular pathway carries information about form, movement, depth, and differences in brightness; the parvocellular pathway carries information on color and fine detail. • The optic chiasma allows us to coordinate information between both eyes and is produced by crossing optical information across the brain. • Visual signals move from the visual cortex to either the parietal lobe or the temporal lobe. • Some signals move to the thalamus, which sends the visual signals to the primary cortex. The suprachiasmatic nucleus (SNC) • Visual signals can also travel from the retina to the superior colliculus, where eye View on Boundless.com movements are coordinated with auditory information. • Visual signals can move from the retina to the suprachiasmatic nucleus (SCN), the body's internal clock, which is involved in sleep/wake patterns and annual cycles. Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell-15/thevertebrate-visual-system-145/visual-processing-762- Special Senses (Vision, Hearing, Taste, and Smell) > Taste and Olfaction Taste and Olfaction • Tastes and Odors • Reception and Transduction Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology?campaign_content=book_299_chapter_15&campaign_term=Physiology&utm_campaign=powerpoint&utm_mediu m=direct&utm_source=boundless Special Senses (Vision, Hearing, Taste, and Smell) > Taste and Olfaction Tastes and Odors • Humans can taste sweet, sour, bitter, salty, and umami; umami is the savoriness of certain foods that are commonly high in protein. • Odors come from molecules in the air that stimulate receptors in the nose; if an organism does not have a receptor for that particular odor molecule, for that organism, the odor has no smell. • The senses of smell and taste are directly related because they both use the same types of receptors. • If one's sense of smell is not functional, then the sense of taste will also not function because of the relationship of the receptors. Uniform Distribution of Taste Receptors View on Boundless.com Free to share, print, make copies and changes. 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Human olfactory system View on Boundless.com Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell-15/tasteand-olfaction-146/reception-and-transduction-764- Special Senses (Vision, Hearing, Taste, and Smell) > Hearing and Equilibrium Hearing and Equilibrium • Sound • The Vestibular System • Reception of Sound • Transduction of Sound Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology?campaign_content=book_299_chapter_15&campaign_term=Physiology&utm_campaign=powerpoint&utm_mediu m=direct&utm_source=boundless Special Senses (Vision, Hearing, Taste, and Smell) > Hearing and Equilibrium Sound • Sound waves are mechanical pressure waves that must travel through a medium and cannot exist in a vacuum. • There are four main characteristics of a sound wave: frequency, wavelength, period, and amplitude. • Frequency is the number of waves per unit of time and is heard as pitch; highfrequency sounds are high-pitched, and low-frequency sounds are low-pitched. • Most humans can perceive sounds with frequencies between 30 and 20,000 Hz; other animals, such as dolphins, can detect sounds at far higher frequencies. • Amplitude, the dimension of a wave from peak to trough, is heard as volume; louder sounds have greater amplitudes than those of softer sounds. Amplitude View on Boundless.com Free to share, print, make copies and changes. 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View on Boundless.com • Neuronal projections to the temporal cortex account for feelings of dizziness; projections to autonomic nervous system areas in the brainstem account for motion sickness; and projections to the primary somatosensory cortex monitor subjective measurements of the external world and self-movement. Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell15/hearing-and-equilibrium-147/the-vestibular-system-766- Special Senses (Vision, Hearing, Taste, and Smell) > Hearing and Equilibrium Reception of Sound • The human ear can be divided into three, fairly-distinct components: the outer ear, the middle ear, and the inner ear. • Sound waves are collected by the pinna, travel through the auditory canal, and cause vibration of the tympanum (ear drum). • The three ossicles of the middle ear (malleus, incus, and stapes) transfer energy from the vibrating ear drum to the inner ear. • The incus connects the malleus to the stapes, which allows vibrations to reach the inner ear. Human ear View on Boundless.com Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell15/hearing-and-equilibrium-147/reception-of-sound-767- Special Senses (Vision, Hearing, Taste, and Smell) > Hearing and Equilibrium Transduction of Sound • The human ear can have three distinct components: the outer ear, which is responsible for gathering sound energy and funneling it to the eardrum; the middle ear, which acts as a mechanical transformer; and the inner ear, where the auditory receptors are located. • The outer ear consists of the visible part of the ear (or pinna), the external auditory canal (meatus), and the tympanic membrane (tympanum) or eardrum. • The human pinna is formed primarily of cartilage and is attached to the head by muscles and ligaments; the deep central portion of the pinna is called the concha, which leads into the external auditory canal. • The middle ear cavity is air-filled while the inner ear is fluid-filled; if sound waves Diagram of the ear View on Boundless.com were to impinge directly on the oval window, the membrane would barely move. • The inner ear includes the semicircular canals, the vestibule, and the cochlea, which contains receptors for transduction of the mechanical wave into an electrical signal. • The inner hair cells are most important for conveying auditory information to the brain. 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Get yours at www.boundless.com www.boundless.com/physiology?campaign_content=book_299_chapter_15&campaign_term=Physiology&utm_campaign=powerpoint&utm_mediu m=direct&utm_source=boundless Special Senses (Vision, Hearing, Taste, and Smell) > Development of Special Senses Taste and Smell at Birth and in Old Age • Newborns are born with odor and taste preferences acquired in the womb from the smell and taste of amniotic fluid, in turn influenced by what the mother eats. • A significant change takes place in the regulation of olfaction just after birth so that odors related with the offspring are no longer aversive, allowing the female to positively respond to her babies. • Anosmia is a lack of functioning olfaction; an inability to perceive odors. • Ageusia is the loss of taste functions of the tongue, particularly the inability to detect sweetness, sourness, bitterness, saltiness, and umami (meaning "pleasant/savory taste"). Olfactory System View on Boundless.com Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell15/development-of-special-senses-148/taste-and-smell-at-birth-and-in-old-age-769- Special Senses (Vision, Hearing, Taste, and Smell) > Development of Special Senses Development of Vision • Organogenesis of the eye is pointed out as an example of a developmental cascade of inductions. • Development of the optic vesicles starts in the three week embryo from a progressively deepening groove in the neural plate called the optic sulcus. • The optic vesicles come into contact with the epithelum and induce the epidermis which will thicken to form the lens placode. • The periocular mesenchyme migrates in during the formation of the optic cup and is critical for the induction of the retinal pigment epithelium and the optic nerve. Chick embryo head with optic vesicle View on Boundless.com Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell15/development-of-special-senses-148/development-of-vision-770- Special Senses (Vision, Hearing, Taste, and Smell) > Development of Special Senses Development of Hearing and Balance • The human inner ear develops during week four of embryonic development from the auditory placode, a thickening of the ectoderm that gives rise to the bipolar neurons of the cochlear and vestibular ganglions. • The auditory vesicle will give rise to the utricluar and saccular components of the membranous labyrinth. • Beginning in the fifth week of development, the auditory vesicle also gives rise to the cochlear duct, which contains the spiral organ of Corti and the endolymph that accumulates in the membranous labyrinth. • In our vestibular system, neurons are undeveloped at neuronal birth and mature during the critical period of the first two to three postnatal weeks. Formation of the Mammalian Ear View on Boundless.com • Many studies have supported a correlation between the type of auditory stimuli present in the early postnatal environment and the development on the topographical and structural development of the auditory system. Free to share, print, make copies and changes. Get yours at www.boundless.com www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/special-senses-vision-hearing-taste-and-smell15/development-of-special-senses-148/development-of-hearing-and-balance-771- Appendix Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Key terms • amplitude measure of a wave from its highest point to its lowest point; heard as volume • anosmia Inability to smell; the inability to perceive odors. • cochlea the complex, spirally coiled, tapered cavity of the inner ear in which sound vibrations are converted into nerve impulses • cone cell located near the center of the retina that is weakly photosensitive and is responsible for color vision in relatively bright light • frequency characterized as a periodic vibration that is audible; property of sound that most determines pitch and is measured in hertz • incus small anvil-shaped bone in the middle ear; connects the malleus to the stapes • inner ear The portion of the ear located within the temporal bone that includes the semicircular canals, vestibule, and cochlea. It is responsible for hearing and balance. • lens placode The lens placode is a thickened portion of ectoderm which serves as the precursor to the lens. • malleus small hammer-shaped bone of the middle ear • odorant any substance that has a distinctive smell, especially one added to something (such as household gas) for safety purposes • olfactory concerning the sense of smell • olfactory bulb The olfactory bulb is a structure of the vertebrate forebrain involved in olfaction, the perception of odors. Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) • optic chiasma found at the base of the brain and coordinates information from both eyes • optic cup During embryonic development of the eye, the outer wall of the bulb of the optic vesicles becomes thickened and invaginated, and the bulb is thus converted into a cup, the optic cup (or ophthalmic cup), consisting of two strata of cells. These two strata are continuous with each other at the cup margin, which ultimately overlaps the front of the lens and reaches as far forward as the future aperture of the pupil. • optic sulcus A progressively deepening groove in the neural plate from which the optic vesicles will develop. • organ of Corti The organ of Corti (or spiral organ) is the organ in the inner ear found only in mammals that contains auditory sensory cells, or "hair cells. " • ossicle a small bone (or bony structure), especially one of the three of the middle ear • papilla a nipple-like anatomical structure • pinna the visible, cartilaginous part of the ear that resides outside of the head and collects sound waves • receptor a protein on a cell wall that binds with specific molecules so that they can be absorbed into the cell in order to control certain functions • retina the thin layer of cells at the back of the eyeball where light is converted into neural signals sent to the brain • rhodopsin a light-sensitive pigment in the rod cells of the retina; it consists of an opsin protein bound to the carotenoid retinal • rod a rod-shaped cell located in the outer retina of the eye that is extremely sensitive to light • stapes small stirrup-shaped bone of the middle ear Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) • stereocilium any of many nonmotile cellular structures resembling long microvilli; those of the inner ear are responsible for auditory transduction • superior colliculus the primary area of the brain where eye movements are coordinated and integrated with auditory information • suprachiasmatic nucleus cluster of cells that is considered to be the body's internal clock, which controls our circadian (daylong) cycle • tastant any substance that stimulates the sense of taste • taste bud Taste buds contain the receptors for taste. They are located around the small structures on the upper surface of the tongue, soft palate, upper esophagus and epiglottis, which are called papillae. • tonic activity when photoreceptors become slightly active even when not stimulated by light • transduce to convert energy from one form to another • tympanum innermost part of the outer ear; the eardrum • ultrasound sound frequencies above the human detectable ceiling of approximately 20,000 Hz • umami one of the five basic tastes, the savory taste of foods such as seaweed, cured fish, aged cheeses and meats • vestibular system The vestibular system, which contributes to balance in most mammals and to the sense of spatial orientation, is the sensory system that provides the leading contribution about movement and sense of balance. • vestibular system the sensory system in mammals that contributes to movement, sense of balance, and spatial orientation Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) • vestibulocochlear of or pertaining to the vestibular and cochlear nerves Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Uniform Distribution of Taste Receptors Humans detect taste using receptors called taste buds. Each of these receptors is specially adapted to determine one type of taste sensation. Recent evidence suggests that taste receptors are uniformly distributed across the tongue; thus, the traditional tongue map is no longer valid. Free to share, print, make copies and changes. Get yours at www.boundless.com Wikimedia Commons. "The Tongue." CC BY-SA 3.0 http://en.wikipedia.org/wiki/File:1402_The_Tongue.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Taste Receptors in Humans Structure of the taste bud Free to share, print, make copies and changes. Get yours at www.boundless.com Wikimedia. "Taste bud." CC BY-SA 3.0 http://commons.wikimedia.org/wiki/File:Taste_bud.svg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Chick embryo head with optic vesicle The eyes make their appearance before the closure of the anterior end of the neural tube. After the closure of the tube they are known as the optic vesicles. Free to share, print, make copies and changes. Get yours at www.boundless.com Wikipedia. "Gray460." CC BY-SA http://en.wikipedia.org/wiki/File:Gray460.png View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Hyperpolarized visual receptors When light strikes rhodopsin, the G-protein transducin is activated, which in turn activates phosphodiesterase. Phosphodiesterase converts cGMP to GMP, thereby closing sodium channels. As a result, the membrane becomes hyperpolarized. The hyperpolarized membrane does not release glutamate to the bipolar cell. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44761/latest/Figure_36_05_05.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Amplitude For sound waves, wavelength corresponds to pitch. The amplitude of the wave corresponds to volume. The sound wave shown with a dashed line is softer in volume than the sound wave shown with a solid line. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44760/latest/Figure_36_04_01.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Rhodopsin (a) Rhodopsin, the photoreceptor in vertebrates, has two parts: the trans-membrane protein opsin and retinal. When light strikes the retinal, it changes shape from (b) a cis to a trans form. The signal is passed to a G-protein called transducin, triggering a series of downstream events. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44761/latest/Figure_36_05_04.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Human ear Sound travels through the outer ear to the middle ear, which is bounded on its exterior by the tympanic membrane. The middle ear contains three bones called ossicles that transfer the sound wave to the oval window, the exterior boundary of the inner ear. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44760/latest/Figure_36_04_02.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Vestibular labrynth The structure of the vestibular labyrinth is made up of five vestibular receptor organs in the inner ear: the utricle, the saccule, and three semicircular canals. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44760/latest/Figure_36_04_04.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Transduction In the human ear, sound waves cause the stapes to press against the oval window. Vibrations travel up the fluid-filled interior of the cochlea. The basilar membrane that lines the cochlea gets continuously thinner toward the apex of the cochlea. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44760/latest/Figure_36_04_03abcf.png View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Uniform distribution of taste receptors (the myth of the tongue map) Humans detect taste using receptors called taste buds. Each of these receptors is specially adapted to determine one type of taste sensation. Recent evidence suggests that taste receptors are uniformly distributed across the tongue; thus, this traditional tongue map is no longer valid. Free to share, print, make copies and changes. Get yours at www.boundless.com Wikispaces. "ehumanbiofield - Sense of Taste WikiPage NLL." CC BY-SA https://ehumanbiofield.wikispaces.com/Sense+of+Taste+WikiPage+NLL View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Taste buds (a) Foliate, circumvallate, and fungiform papillae are located on different regions of the tongue. (b) Foliate papillae are prominent protrusions on this light micrograph. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44764/latest/Figure_36_03_03.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Retina (a) The human eye is shown in cross section. The human eye contains structures, such as the cornea, iris, lens, and fovea, that process light so it can be deciphered by the retina. Other structures like the aqueous humor and the vitreous humor help maintain the shape of the eye. (b) A blowup shows the layers of the retina. The retina contains photoreceptive cells. In the retina, light is converted into neural signals sent to the brain. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44761/latest/Figure_36_05_02.png View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) The inner ear The inner ear can be divided into three parts: the semicircular canals, the vestibule, and the cochlea, all of which are located in the temporal bone. Free to share, print, make copies and changes. Get yours at www.boundless.com The Open University. CC BY-SA http://labspace.open.ac.uk/mod/resource/view.php?id=415639 View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Diagram of the ear The ear can be broken up into three distinct sections: the outer ear, the middle ear, and the inner ear. Each section has its own complex functions that aid in transmission of sound via nerve impulses to our brains for processing. Free to share, print, make copies and changes. Get yours at www.boundless.com The Open University. CC BY http://labspace.open.ac.uk/mod/resource/view.php?id=415637 View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Rods and cones Rods and cones are photoreceptors in the retina. Rods respond in low light and can detect only shades of gray. Cones respond in intense light and are responsible for color vision. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44761/latest/Figure_36_05_03.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) The suprachiasmatic nucleus (SNC) The presence of light and darkness influences circadian rhythms and related physiology and behavior through the SCN. Free to share, print, make copies and changes. Get yours at www.boundless.com Wikipedia. "Suprachiasmatic nucleus." GNU FDL http://en.wikipedia.org/wiki/Suprachiasmatic_nucleus View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Olfactory System Human olfactory system. 1: Olfactory bulb 2: Mitral cells 3: Bone 4: Nasal epithelium 5: Glomerulus (olfaction) 6: Olfactory receptor cells Free to share, print, make copies and changes. Get yours at www.boundless.com Wikipedia. "Olfactory system." CC BY-SA http://en.wikipedia.org/wiki/File:Olfactory_system.svg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) The Optic Stalk and Optic Cup During embryonic development of the eye, the outer wall of the bulb of the optic vesicles becomes thickened and invaginated, and the bulb is thus converted into a cup, the optic cup. Free to share, print, make copies and changes. Get yours at www.boundless.com Wikipedia. "Gray865." CC BY-SA http://en.wikipedia.org/wiki/File:Gray865.png View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Human olfactory system In the human olfactory system, (a) bipolar olfactory neurons extend from (b) the olfactory epithelium, where olfactory receptors are located, to the olfactory bulb. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. "Print." CC BY 3.0 http://cnx.org/content/m44764/latest/Figure_36_03_01.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Formation of the Mammalian Ear The cochlea and vestibule viewed from above. Free to share, print, make copies and changes. Get yours at www.boundless.com Wikipedia. "Gray923." Public domain http://en.wikipedia.org/wiki/File:Gray923.png View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Rod and cone cells Human rod cells and the different types of cone cells each have an optimal wavelength. However, there is considerable overlap in the wavelengths of light detected. Free to share, print, make copies and changes. Get yours at www.boundless.com Connexions. CC BY 3.0 http://cnx.org/content/m44761/latest/Figure_36_05_06.jpg View on Boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Why is it easier to see at night using peripheral vision rather than acute vision? A) cones are denser in the outer edges of the retina B) rods are denser in the fovea of the retina C) cones are denser in the fovea of the retina D) rods are denser in the outer edges of the retina Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Why is it easier to see at night using peripheral vision rather than acute vision? A) cones are denser in the outer edges of the retina B) rods are denser in the fovea of the retina C) cones are denser in the fovea of the retina D) rods are denser in the outer edges of the retina Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following about the human eye is true? A) the fovea is responsible for peripheral vision B) rods detect color, while cones detect shades of gray C) the iris regulates how much light enters the eye D) the retina is a muscular ring lying between the lens and cornea Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following about the human eye is true? A) the fovea is responsible for peripheral vision B) rods detect color, while cones detect shades of gray C) the iris regulates how much light enters the eye D) the retina is a muscular ring lying between the lens and cornea Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following is true about the trichromatic system? A) It involves two types of cones. B) S cones respond maximally to waves at 530 nm. C) Different cones still have the same photopsins. D) M cones respond maximally to waves at 530 nm. Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following is true about the trichromatic system? A) It involves two types of cones. B) S cones respond maximally to waves at 530 nm. C) Different cones still have the same photopsins. D) M cones respond maximally to waves at 530 nm. Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) How is visual information processed in the retina? A) Light hyperpolarizes rods and cones. B) Photoreceptors become inactived by the presence of light. C) Light depolarizes rods and cones. D) Ganglion cells are inhibited by rods and cons. Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) How is visual information processed in the retina? A) Light hyperpolarizes rods and cones. B) Photoreceptors become inactived by the presence of light. C) Light depolarizes rods and cones. D) Ganglion cells are inhibited by rods and cons. Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following events must take place for transduction of light to occur? A) The retinal changes shape from trans to cis. B) The opsin changes shape from trans to cis. C) The retinal changes shape from cis to trans. D) The opsin changes shape from cis to trans. Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following events must take place for transduction of light to occur? A) The retinal changes shape from trans to cis. B) The opsin changes shape from trans to cis. C) The retinal changes shape from cis to trans. D) The opsin changes shape from cis to trans. Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following is true about visual processing? A) Axons carry visual signals from the optic nerve to the brain. B) Visual signals always travel through the visual cortex. C) All visual signals carry parvocellular information. D) Visual signals all follow one pathway that leads to the midbrain. Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following is true about visual processing? A) Axons carry visual signals from the optic nerve to the brain. B) Visual signals always travel through the visual cortex. C) All visual signals carry parvocellular information. D) Visual signals all follow one pathway that leads to the midbrain. Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Why are the senses of taste and smell related to each other? A) both senses use the same type of receptors B) both senses are connected to the same portion of the brain C) both senses arise from within the same organs D) both senses cause molecules to be released from a substance's surface Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Why are the senses of taste and smell related to each other? A) both senses use the same type of receptors B) both senses are connected to the same portion of the brain C) both senses arise from within the same organs D) both senses cause molecules to be released from a substance's surface Free to share, print, make copies and changes. Get yours at www.boundless.com OpenStax OER. "Biology." CC BY 3.0 http://cnx.org/content/col11448/latest Special Senses (Vision, Hearing, Taste, and Smell) Which of these describes how a sour taste would be detected? A) an acid molecule attaches itself to a thermoreceptor and causes an increase in H+ ions B) a tastant attaches to a G-protein receptor and causes a depolarization of the membrane C) sodium ions enter the receptor and excite it from the inside D) molecules in the air stimulate receptors in the nose, which then send the signal to the taste buds Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of these describes how a sour taste would be detected? A) an acid molecule attaches itself to a thermoreceptor and causes an increase in H+ ions B) a tastant attaches to a G-protein receptor and causes a depolarization of the membrane C) sodium ions enter the receptor and excite it from the inside D) molecules in the air stimulate receptors in the nose, which then send the signal to the taste buds Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Frequency is heard as ___ , while amplitude is heard as ____. A) volume; pitch B) loudnes; quickness C) soft; loud D) pitch; volume Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Frequency is heard as ___ , while amplitude is heard as ____. A) volume; pitch B) loudnes; quickness C) soft; loud D) pitch; volume Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following is part of the inner ear to help maintain an animal's balance? A) all of these B) the utricle C) auditory transponder D) cochlear nerve Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following is part of the inner ear to help maintain an animal's balance? A) all of these B) the utricle C) auditory transponder D) cochlear nerve Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the vestibular organs are most responsive to gravitational changes? A) semicircle canals B) only the utricle C) utricle and saccule D) utricle, saccule, and the semicircle canals Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the vestibular organs are most responsive to gravitational changes? A) semicircle canals B) only the utricle C) utricle and saccule D) utricle, saccule, and the semicircle canals Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following explains how animals sense sound? A) The outer ear gathers sound energy, the middle ear transforms it, and the inner ear processes electrical signals. B) The incus gathers sound energy, the malleus transforms it, and the stapes processes electrical signals. C) The outer ear gathers sound energy, the eardrum transforms it, and the inner ear processes electrical signals. D) The eardrum gathers sound energy, the outer ear transforms it, and the ossicles process electrical signals. Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following explains how animals sense sound? A) The outer ear gathers sound energy, the middle ear transforms it, and the inner ear processes electrical signals. B) The incus gathers sound energy, the malleus transforms it, and the stapes processes electrical signals. C) The outer ear gathers sound energy, the eardrum transforms it, and the inner ear processes electrical signals. D) The eardrum gathers sound energy, the outer ear transforms it, and the ossicles process electrical signals. Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Auditory hair cells are indirectly anchored to the _____. A) oval window B) basilar membrane C) tectorial membrane D) ossicles Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Auditory hair cells are indirectly anchored to the _____. A) oval window B) basilar membrane C) tectorial membrane D) ossicles Free to share, print, make copies and changes. Get yours at www.boundless.com OpenStax OER. "Biology." CC BY 3.0 http://cnx.org/content/col11448/latest Special Senses (Vision, Hearing, Taste, and Smell) The middle ear acts as a _____ . A) funnel for sounds B) mechanical transformer for sounds C) auditory receptor for sounds D) frequency reader for sounds Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) The middle ear acts as a _____ . A) funnel for sounds B) mechanical transformer for sounds C) auditory receptor for sounds D) frequency reader for sounds Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following statements about tasting and smelling at birth and in old age is FALSE? A) Newborns are born with odor and taste preferences acquired in the womb B) Olfactory learning only occurs in the infant and not within the mother C) Ageusia, the loss of taste functions of the tongue, is associated aging D) Anosmia, a lack of functioning olfaction, is associated with old age Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following statements about tasting and smelling at birth and in old age is FALSE? A) Newborns are born with odor and taste preferences acquired in the womb B) Olfactory learning only occurs in the infant and not within the mother C) Ageusia, the loss of taste functions of the tongue, is associated aging D) Anosmia, a lack of functioning olfaction, is associated with old age Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following IS NOT one of the three tissues from which the eyes develop? A) Neural tube B) Epidermis C) optoderm D) Periocular mesenchyme Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following IS NOT one of the three tissues from which the eyes develop? A) Neural tube B) Epidermis C) optoderm D) Periocular mesenchyme Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Which of the following statement(s) regarding the development of hearing and balance is/are true? A) The inner ear starts to develop during embryonic week four B) Critical periods exist for hearing and the vestibular system C) All of the statements regarding hearing and balance are true D) At embryonic week five the cochlear duct begins to develop Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) Which of the following statement(s) regarding the development of hearing and balance is/are true? A) The inner ear starts to develop during embryonic week four B) Critical periods exist for hearing and the vestibular system C) All of the statements regarding hearing and balance are true D) At embryonic week five the cochlear duct begins to develop Free to share, print, make copies and changes. Get yours at www.boundless.com Boundless - LO. "Boundless." CC BY-SA 3.0 http://www.boundless.com/ Special Senses (Vision, Hearing, Taste, and Smell) Attribution • Wikipedia. "Olfactory memory." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Olfactory_memory • Wikipedia. "Olfactory memory." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Olfactory_memory • Wikipedia. "Developmental psychology." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Developmental_psychology • Wikipedia. "Developmental psychology." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Developmental_psychology • Wikipedia. "Loss of taste." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Loss_of_taste • Wikipedia. "Loss of smell." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Loss_of_smell • Wiktionary. "anosmia." CC BY-SA 3.0 http://en.wiktionary.org/wiki/anosmia • Wikipedia. "Taste bud." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Taste_bud • Wikipedia. "taste bud." CC BY-SA 3.0 http://en.wikipedia.org/wiki/taste%20bud • Wikipedia. "olfactory bulb." CC BY-SA 3.0 http://en.wikipedia.org/wiki/olfactory%20bulb • Wikipedia. "Olfactory memory." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Olfactory_memory • Wikipedia. "Inner ear." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Inner_ear#Embryology • Wikipedia. "Critical period." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Critical_period#Vestibular_System • Wikipedia. "organ of Corti." CC BY-SA 3.0 http://en.wikipedia.org/wiki/organ%20of%20Corti • Boundless Learning. "Boundless." CC BY-SA 3.0 http://www.boundless.com//biology/definition/vestibular-system • Wiktionary. "inner ear." CC BY-SA 3.0 http://en.wiktionary.org/wiki/inner+ear • Wikipedia. "Critical period." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Critical_period#Vestibular_System Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) • Wikipedia. "Eye development." CC BY-SA 3.0 http://en.wikipedia.org/wiki/Eye_development • Wikipedia. "optic cup." CC BY-SA 3.0 http://en.wikipedia.org/wiki/optic%20cup • Wikipedia. "optic sulcus." CC BY-SA 3.0 http://en.wikipedia.org/wiki/optic%20sulcus • Wikipedia. "lens placode." CC BY-SA 3.0 http://en.wikipedia.org/wiki/lens%20placode • Wiktionary. "receptor." CC BY-SA 3.0 http://en.wiktionary.org/wiki/receptor • Wiktionary. "olfactory." CC BY-SA 3.0 http://en.wiktionary.org/wiki/olfactory • Wiktionary. "umami." CC BY-SA 3.0 http://en.wiktionary.org/wiki/umami • Wikispaces. "VirtualGardnerAnatPhys - Smell Fall 2011." CC BY-SA https://virtualgardneranatphys.wikispaces.com/Smell+Fall+2011 • Connexions. "Taste and Smell." CC BY 3.0 http://cnx.org/content/m44764/latest/?collection=col11448/latest • Connexions. "Taste and Smell." CC BY 3.0 http://cnx.org/content/m44764/latest/?collection=col11448/latest • Wiktionary. "odorant." CC BY-SA 3.0 http://en.wiktionary.org/wiki/odorant • Wiktionary. "tastant." CC BY-SA 3.0 http://en.wiktionary.org/wiki/tastant • Wiktionary. "papilla." CC BY-SA 3.0 http://en.wiktionary.org/wiki/papilla • Connexions. "Hearing and Vestibular Sensation." CC BY 3.0 http://cnx.org/content/m44760/latest/?collection=col11448/latest • Boundless Learning. "Boundless." CC BY-SA 3.0 http://www.boundless.com//biology/definition/ultrasound • Wiktionary. "amplitude." CC BY-SA 3.0 http://en.wiktionary.org/wiki/amplitude • Wiktionary. "frequency." CC BY-SA 3.0 http://en.wiktionary.org/wiki/frequency • Connexions. "Hearing and Vestibular Sensation." CC BY 3.0 http://cnx.org/content/m44760/latest/?collection=col11448/latest • Boundless Learning. "Boundless." CC BY-SA 3.0 http://www.boundless.com//biology/definition/tympanum Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) • Wiktionary. "pinna." CC BY-SA 3.0 http://en.wiktionary.org/wiki/pinna • Wiktionary. "stapes." CC BY-SA 3.0 http://en.wiktionary.org/wiki/stapes • Wiktionary. "incus." CC BY-SA 3.0 http://en.wiktionary.org/wiki/incus • Wiktionary. "malleus." CC BY-SA 3.0 http://en.wiktionary.org/wiki/malleus • The Open University. CC BY-SA http://labspace.open.ac.uk/mod/resource/view.php?id=415635 • Connexions. "Hearing and Vestibular Sensation." CC BY 3.0 http://cnx.org/content/m44760/latest/?collection=col11448/latest • The Open University. CC BY-SA http://labspace.open.ac.uk/mod/resource/view.php?id=415635 • Wiktionary. "cochlea." CC BY-SA 3.0 http://en.wiktionary.org/wiki/cochlea • Wiktionary. "ossicle." CC BY-SA 3.0 http://en.wiktionary.org/wiki/ossicle • Wiktionary. "transduce." CC BY-SA 3.0 http://en.wiktionary.org/wiki/transduce • The Open University. CC BY-SA http://labspace.open.ac.uk/mod/resource/view.php?id=415637 • Connexions. "Hearing and Vestibular Sensation." CC BY 3.0 http://cnx.org/content/m44760/latest/?collection=col11448/latest • Boundless Learning. "Boundless." CC BY-SA 3.0 http://www.boundless.com//biology/definition/vestibular-system • Wiktionary. "vestibulocochlear." CC BY-SA 3.0 http://en.wiktionary.org/wiki/vestibulocochlear • Wiktionary. "stereocilium." CC BY-SA 3.0 http://en.wiktionary.org/wiki/stereocilium • Wikibooks. "Ophthalmology/Anatomy of the Eye." CC BY-SA 3.0 http://en.wikibooks.org/wiki/Ophthalmology/Anatomy_of_the_Eye • Connexions. "Vision." CC BY 3.0 http://cnx.org/content/m44761/latest/?collection=col11448/latest • Wiktionary. "cone." CC BY-SA 3.0 http://en.wiktionary.org/wiki/cone • Wiktionary. "rod." CC BY-SA 3.0 http://en.wiktionary.org/wiki/rod Free to share, print, make copies and changes. Get yours at www.boundless.com Special Senses (Vision, Hearing, Taste, and Smell) • Wiktionary. "retina." CC BY-SA 3.0 http://en.wiktionary.org/wiki/retina • Connexions. "Vision." CC BY 3.0 http://cnx.org/content/m44761/latest/?collection=col11448/latest • Wiktionary. "transduction." CC BY-SA 3.0 http://en.wiktionary.org/wiki/transduction • Boundless Learning. "Boundless." CC BY-SA 3.0 http://www.boundless.com//biology/definition/tonic-activity • Wiktionary. "rhodopsin." CC BY-SA 3.0 http://en.wiktionary.org/wiki/rhodopsin • Connexions. "Vision." CC BY 3.0 http://cnx.org/content/m44761/latest/?collection=col11448/latest • Boundless Learning. "Boundless." CC BY-SA 3.0 http://www.boundless.com//biology/definition/optic-chiasma • Boundless Learning. "Boundless." CC BY-SA 3.0 http://www.boundless.com//biology/definition/suprachiasmatic-nucleus • Boundless Learning. "Boundless." CC BY-SA 3.0 http://www.boundless.com//biology/definition/superior-colliculus Free to share, print, make copies and changes. Get yours at www.boundless.com
