Human Anatomy and Physiology I

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Human Anatomy and Physiology I

• Chapter 15
• Dr. Ackman

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Anatomy and Physiology

• Special Senses
• Special receptor cells
• Smell
• Olfaction
• Taste
• Gustation
• Hearing
• Auditory
• Sight
• Vision

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Anatomy and Physiology

• Taste
• Chemoreceptors
• Respond to chemicals in an aqueous solution
• Taste buds
• Sensory receptor organs of taste
• 10,000 located in oral cavity
• Most found in papillae of the tongue

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Anatomy and Physiology

• Taste bud are found in papillae
• Filiform
• Fungiform
• Mushroom shaped
• Scattered
• Tip and sides
• Circumvallate
• Inverted V shape
• Larger
• Fewest
• Posterior of tongue

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Anatomy and Physiology

• Taste buds
• Three cell types
• Supporting cells
• Insulate gustatory cells
• Bulk of taste buds
• Gustatory cells
• Gustatory hairs exit through taste pore
• Afferent fibers attached
• Basal cells
• Stem cell of the taste bud

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Anatomy and Physiology

• Taste sensations
• Sweet
• Organic solutions
• Sour
• Acidic solutions
• Salty
• Metal ions
• Bitter
• Alkaloids

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Anatomy and Physiology

• Physiology of taste
• In aqueous solution
• Binding to receptors
• Depolarizing potential
• Release of neurotransmitter
• Sensory dendrites
• Action potential in afferent nerve

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Anatomy and Physiology

• Gustatory pathway
• Afferent nerves
• Facial nerve (VII)
• Glossopharyngeal (IX)
• Medulla
• Solitary nucleus
• Thalamus
• Gustatory cortex of parietal lobes
• Hypothalamus and limbic system
• Enjoyment or aversion to taste

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Anatomy and Physiology

• Smell
• Olfactory center
• Olfactory epithelium
• Yellow tinged structure
• Pseudostratified epithelium
• Roof of nasal cavity

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Anatomy and Physiology

• Smell
• Olfactory receptors
• Olfactory cilia
• Increase receptor surface area
• Supporting cells
• Columnar cells
• Bulk of epithelial membrane
• Basal cells
• Stem cells

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Anatomy and Physiology

• Smell
• Receptor potential
• Olfactory bulbs
• Mitral cells
• Refine signal
• Amplify signal
• Relay signal
• Granule cells
• Inhibit mitral cells
• Olfactory inhibition

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Anatomy and Physiology
13
Anatomy and Physiology

• Structures of the eye
• Accessory structures
• Eyebrows
• Shade eyes
• Prevent sweat from entering
• Eyelids
• Palpebra
• Flesh covered tarsal plates
• Lateral /medial canthus or commisure
• Lacrimal caruncle
• Sebaceous gland

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Anatomy and Physiology

• Eyelids
• Meibomian glands
• Associated with eyelash follicle
• Secrete oily substance
• Chalazion infection of Meibomian gland
• Sty inflammation of smaller glands
• Eyelashes
• Cilia
• Rich nerve root plexus

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Anatomy and Physiology

• Conjunctiva
• Transparent mucus membrane
• Palpebral
• Ocular
• Conjunctival sac
• Contact lens
• Produces lubricating mucus
• Conjunctivitis
• Pinkeye

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Anatomy and Physiology

• Lacrimal apparatus
• Lacrimal gland
• Produces tears
• Lysozyme
• Spread by blinking
• Lacrimal puncta
• Hole in lids of medial canthus
• Lacrimal canals
• Drain to lacrimal sac
• Lacrimal sac
• Nasolacrimal duct

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Anatomy and Physiology

• Extrinsic eye muscles
• Moves eye
• Laterally
• Medially
• Elevates eye
• Depresses eye
• Elevates and turns laterally
• Depresses and turns laterally
• Controlled by cranial nerves
• Occulomotor (III)
• Abducens (VI)
• Trochlear (V)

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Anatomy and Physiology

• Eye movements
• Saccades
• Small jerky motions
• Scanning movements
• Tracking movements
• Fix on object while head moves

• Abnormal eye movements
• Diplopic
• Double vision
• Strabismus
• Cross eyed
• Eye rotates medially or laterally

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Anatomy and Physiology

• Eyeball
• Anterior/ posterior poles
• Wall (3 tunics)
• Fibrous
• Sclera
• Cornea
• Vascular
• Uvea
• Choroid
• Ciliary body
• Iris
• Sensory
• Retina

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Anatomy and Physiology

• Pupil
• Controlled by two smooth muscle layer of the iris
• Circular
• Radial

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Anatomy and Physiology

• Retina layer
• Pigmented layer
• Absorbs light
• Phagocytes
• Stores Vitamin A
• Neural layer
• Photoreceptors
• Rods
• Dim light
• Peripheral
• Cones
• Color vision
• Detached retina pigmented and neural layer
  separate

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Anatomy and Physiology

• Retina
• Fundus
• Posterior wall of retina
• Macula lutea
• Light passes easily
• Sight most acute vision
• Fovea centralis
• Contains only cones
• Less concentrated as progress to periphery
• Acute vision center
• Optic disc
• Blind spot
• Optic nerve exits

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Anatomy and Physiology

• Retinal blood supply
• Central artery
• Central vein
• Retinal vessels
• Characteristic to individual

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Anatomy and Physiology

• Posterior segment
• Behind lens
• Vitreous humor (body)
• Gelatinous material
• Transmits light
• Supports lens
• Holds neural layer against pigmented layer
• Intraocular pressure

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Anatomy and Physiology

• Anterior segment
• Anterior chamber
• Between cornea and iris
• Posterior chamber
• Between lens and iris
• Filled with aqueous humor
• Similar to plasma

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Anatomy and Physiology

• Aqueous humor
• Capillaries of ciliary processes
• Posterior chamber
• Pupil
• Anterior chamber
• Canal of Schlemm
• Glaucoma increased intraocular pressure caused
  by impairment of aqueous humor drainage

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Anatomy and Physiology

• Lens
• Biconvex
• Enclosed in thin capsule
• Two parts
• Lens epithelium
• Lens fibers
• No nuclei
• Bulk of lens
• Folded proteins
• Crystallins
• Cataract
• Age
• Diabetes mellitus
• Lens becomes hardened and thickened

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Anatomy and PHysiology

• Problems of vision
• Emmetric eye
• Focal point focuses on retinal surface
• Myopic
• Near sighted
• Image focal point falls short of retinal surface
• Hyperopic
• Far sighted
• Image focal point falls behind retinal surface

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Anatomy and Physiology

• Corrective lenses
• Myopic
• Concave lens
• Hyperopic
• Convex lens

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Anatomy and Physiology

• Photoreception
• Photoreceptors
• Outer segment
• Visual pigments
• Change shape when exposed to light
• Embedded in pigmented layer
• Inner segment

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Anatomy and Physiology

• Rods
• Sensitive to dim light
• Night and peripheral vision
• Absorb all wavelengths of visible light
• Perceive only gray tones
• Converging pathways
• Contain pigment rhodopsin
• Accumulates in dark
• Derived from Vitamin A

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Anatomy and Physiology

• Cones
• Need bright light
• Vivid color
• Acute vision
• Concentrated at fovea
• Each cone has straight path to bipolar cell
• Types of cones
• Blue cones
• Green cones
• Red cones

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Anatomy and Physiology

• Visual pathway
• Photorecpetor
• Bipolar ganglion
• Optic nerve
• Optic chiasm
• Lateral geniculate nuclei
• Primary visual cortex
• Occipital lobe

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Anatomy and Physiology

• Structure of the ear
• 3 area
• External ear
• Middle ear
• Inner ear

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Anatomy annd Physiology

• External ear
• Pinna
• Elastic cartilage
• External auditory meatus
• Ear canal
• Ceruminous glands
• Cerumen
• Ear wax
• Tympanic membrane
• Eardrum

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Anatomy and PHysiololgy

• Middle ear
• Tympanic cavity
• Oval window
• Round window
• Pharygotympanic tube
• Ossicles
• Incus
• Malleus
• Handle attached to tympanic membrane
• Stapes

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Anatomy and Physiology

• Inner ear
• Housed in temporal bone
• Labyrinth
• Membranous
• Bony
• Semicircular canals
• Membranous labyrinth
• Surrounded by perilymph
• Houses endolymph

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Anatomy and Physiology

• Inner Ear
• Vestibule
• Sacule
• Labyrinth sac continuous with membranous
  labyrinth
• Macula
• Equilibrium receptors
• Utricle
• Labyrinth sac continuous with semicircular canals
• Maculae
• Equilibrium receptors

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Anatomy and Physiology

• Inner ear
• Semicircular canals
• Inner semicircular duct
• Crista ampullaris
• Angular rotation of head

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Anatomy and Physiology

• Cochlea
• Houses organ of Corti
• Organ of hearing
• Stereocilia
• Movement causes transduction of sound stimuli
• Deafness
• Hearing loss
• Conduction
• Sound conduction is hampered
• otosclerosis
• Sensorineuronal
• Cerebral, neural