Anatomy and Physiology - Special Senses

Flashcards covering key vocabulary terms and definitions from the lecture notes on special senses (smell, taste, vision, hearing, and equilibrium).

What is olfaction?

The sense of smell.

Gustation

Sense of taste

Limbic System

Brain part evoking strong emotions/memories related to smell/taste

Five Primary Tastes

Sour, sweet, bitter, salty, umami

Olfactory Epithelium

Nasal cavity area with olfactory receptor, supporting, and basal cells

Olfactory Receptor Cells

Bipolar neurons with olfactory hairs; respond to odorants

Supporting Cells (Olfactory)

Detoxify chemicals, insulate receptors, support olfactory cells

Basal Cells (Olfactory)

Produce new olfactory receptor cells

Odorant Binding Proteins

Bind odorants, produce generator potential, lead to action potential

Rapid Adaptation (Olfaction)

Sensitivity decrease after stimulation

Olfactory Nerves

Axons from bipolar olfactory receptor cells

Olfactory Bulb

Gray matter bundle below frontal lobe where receptor cells synapse

Olfactory Tract

Axons projecting to cerebral cortex for smell awareness

Papillae

Tongue elevations with taste buds or tactile receptors

Gustatory Receptor Cells

Cells in taste buds with gustatory hairs; respond to tastants

Supporting Cells (Taste)

Surround receptor cells in taste buds

Basal Cells (Taste)

Stem cells that produce supporting cells in taste buds

Tastants

Dissolved chemicals binding to gustatory hairs, leading to receptor potential

Quick Adaptation (Gustation)

Sensitivity decrease after stimulation

Gustatory Pathway Cranial Nerves

Facial, Glossopharyngeal, Vagus

Primary Gustatory Area

Parietal lobe area for conscious taste perception

Eyelids

Shade, protect, and lubricate the eye

Conjunctiva

Mucous membrane lining eyelids and eyeball surface

Lacrimal Apparatus

Structures producing/draining lacrimal fluid (tears)

Lacrimal Fluid

Fluid with water, salts, mucus, lysozyme; cleans and lubricates the eyeball

Extrinsic Eye Muscles

Move the eyeball

Fibrous Tunic

Avascular layer of eyeball: sclera and cornea

Vascular Tunic

Middle layer of eyeball: choroid, ciliary body, iris

Retina

Innermost layer of eyeball; beginning of visual pathway

Lens

Transparent structure focusing images on retina

Sclera

Tough, white, protective posterior part of eyeball

Cornea

Curved, transparent anterior part of eyeball for light transmission

Choroid

Supplies nutrients, absorbs scattered light

Ciliary Body

Secretes aqueous humor, controls lens shape

Iris

Regulates pupil diameter

Optic Disc

Optic nerve site; 'blind spot'

Fovea Centralis

Highest visual acuity and color vision area

Pigmented Layer (Retina)

Epithelial cells preventing light scattering

Neural Layer (Retina)

Contains photoreceptors, bipolar, and ganglion cells for visual data

Rods

Photoreceptors for night or dim vision

Cones

Photoreceptors for color vision

Aqueous Humor

Fluid in anterior eye cavity; constantly replaced

Vitreous Body

Jelly-like substance holding retina against choroid

Refraction

Bending of light rays focusing image on retina

Accommodation

Increase in lens curvature for near vision

Myopia

Nearsightedness

Hyperopia

Farsightedness

Astigmatism

Partial image distortion

Constriction of Pupil

Autonomic reflex preventing light entry at lens periphery

Convergence

Medial eyeball movement for binocular vision

Photopigments

Proteins in photoreceptors for light energy transduction

Opsin

Glycoprotein component of photopigments

Retinal

Light-absorbing part of photopigment; Vitamin A derivative

Bleaching

Separation of trans-retinal from opsin

Regeneration

Binding of cis-retinal to opsin

Visual Field

Nasal and temporal halves of what eye can see

Light and Dark Adaptation

Photoreceptor adjustment to light level

External Ear

Collects and channels sound waves inward

Middle Ear

Conveys sound vibrations to oval window

Inner Ear

Receptors for hearing and equilibrium

Auricle

Collects sound waves

External Auditory Canal

Carries sound waves to tympanic membrane

Tympanic Membrane

Eardrum; separates external ear from middle ear

Auditory Ossicles

Bones in middle ear: malleus, incus, stapes

Auditory Tube

Connects middle ear to nasopharynx; equalizes pressure

Bony Labyrinth

Cavities in temporal bone containing perilymph

Membranous Labyrinth

Sacs/tubes inside bony labyrinth containing endolymph

Vestibule

Inner ear part: utricle and saccule

Semicircular Canals

Canals in inner ear; contain semicircular ducts

Cochlea

Spiral canal containing cochlear duct

Spiral Organ

Epithelial cells on basilar membrane; contains hair cells

Tectorial Membrane

Gelatinous membrane over the spiral organ

Frequency (Sound)

Wave number; interpreted as pitch

Intensity (Sound)

Wave amplitude; interpreted as loudness

Vestibular Apparatus

Receptor organs for equilibrium

Static Equilibrium

Body orientation relative to gravity

Dynamic Equilibrium

Maintaining position during rotational movement

Maculae

Sense organs in utricle and saccule

Cristae

Sense organs in semicircular canals