Site where merges with cornea

Palpebral Pupil fissure Lateral Medial commissure commissure () (canthus) Iris (covered by Eyelid conjunctiva)

© 2018 Pearson Education, Inc. 1

Lacrimal Excretory gland of Conjunctiva

Anterior aspect

Eyelid

Eyelashes Tarsal glands (a) Eyelid

© 2018 Pearson Education, Inc. 2 Lacrimal gland

Excretory ducts of lacrimal gland

Lacrimal canaliculus

Nasolacrimal duct

Inferior meatus of

Nostril

(b) © 2018 Pearson Education, Inc. 3

Superior oblique muscle

Superior oblique tendon

Conjunctiva

Lateral rectus muscle

Optic Inferior Inferior rectus oblique (a) muscle muscle

© 2018 Pearson Education, Inc. 4 Sclera

Ciliary body Choroid Ciliary zonule Retina

Cornea Fovea centralis Iris

Pupil Optic nerve Aqueous humor (in anterior segment)

Lens

Scleral venous sinus Central (canal of Schlemm) and of Vitreous humor the retina (in posterior segment) Optic disc (blind spot) (a)

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Pigmented layer of retina Rod Cone

Bipolar cells

Ganglion Pathway cells of light (a)

© 2018 Pearson Education, Inc. 6 Pigmented layer of Neural layer retina of retina

Central artery and vein of retina

Optic disc

Sclera Optic Choroid (b) nerve © 2018 Pearson Education, Inc. 7

Visible light

420 nm 530 nm (blue cones) (green cones) 560 nm (red cones) Light absorption by cone populations cone by absorption Light

400 450 500 550 600 650 700 Wavelength (nanometers) © 2018 Pearson Education, Inc. 8 Fovea Macula Blood Optic disc Retina centralis vessels

Lateral Medial

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External (outer) ear Middle ear Internal (inner) ear

Vestibulocochlear nerve Auricle (pinna) Semicircular canals Oval window Cochlea Vestibule

Round window

Pharyngotympanic (auditory) tube

Tympanic membrane (eardrum) Hammer Anvil Stirrup (malleus) (incus) (stapes) External acoustic meatus Auditory ossicles (auditory canal) © 2018 Pearson Education, Inc. 10 Semicircular canals Ampulla Vestibular nerve

Vestibule

(a)

© 2018 Pearson Education, Inc. 11

Force of Otolithic Otoliths gravity membrane Hair cell

Head upright Head tilted (b) © 2018 Pearson Education, Inc. 12 Flow of endolymph

Cupula Nerve fibers Direction of body (c) movement © 2018 Pearson Education, Inc. 13

Temporal Perilymph in scala vestibuli bone Spiral Vestibular organ of membrane Corti Afferent fibers of the cochlear nerve Temporal bone

Cochlear duct (contains Perilymph in endolymph) scala tympani (a) © 2018 Pearson Education, Inc. 14 Vestibular Hair (receptor) Tectorial membrane cells of spiral membrane organ of Corti

Fibers of Basilar Supporting the cochlear membrane cells nerve (b)

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EXTERNAL EAR MIDDLE EAR INTERNAL EAR

Auditory Ear- Hammer, Oval Fluids in cochlear canals Pinna canal drum anvil, stirrup window Upper and middle lower Pressure

Spiral organ Time Amplification Amplitude of Corti One in middle ear vibration stimulated

© 2018 Pearson Education, Inc. 16 Stapes Fibers of Scala sensory vestibuli neurons Oval Perilymph window

Round Scala Basilar Cochlear window tympani membrane duct (a)

Fibers of basilar membrane

Apex Base (short, (long, stiff fibers) floppy fibers) 20,000 2,000 200 20 (High notes) (Low notes) (b) Frequency (Hz) © 2018 Pearson Education, Inc. 17

Olfactory bulb

Cribriform plate of Olfactory tract Olfactory filaments of the olfactory nerve

Supporting cell Olfactory Olfactory receptor mucosa cell

Olfactory hairs Mucus layer (a) (cilia) Route of inhaled air containing odor molecules (b)

© 2018 Pearson Education, Inc. 18 Epiglottis

Palatine tonsil Lingual tonsil

Foliate papillae

Fungiform papillae

(a) © 2018 Pearson Education, Inc. 19

Epithelium of tongue

Taste bud

Connective tissue

Surface of the tongue Gustatory () cell

Basal cell

Sensory nerve fiber

Gustatory hairs (microvilli) emerging from a taste pore (c) © 2018 Pearson Education, Inc. 20