Sensory System- Chapter 44 Flashcards
sense external stimuli
exteroceptors
sense internal stimuli
interoceptors
stimulated by mechanical forces such as pressure
mechanoreceptors
detect chemicals or chemical changes
chemoreceptors
react to electromagnetic and thermal energy
energy-detecting receptors
four step process of sensory receptors
(1) stimulation
(2) transduction-receptor potential in sensory cell created
(3) transmission- action potential in sensory neuron
(4) interpretation- CNS processing
sensory cells respond to stimuli via _____________ in their membranes, depolarize receptors referred to as _____________
stimulus-gated ion channels
receptor potential
transmit impulses based on cell damage, perceived as pain, most are at free nerve endings
nociceptors
naked dendritic endings of sensory neurons, sensitive to changes in temperature, cold receptors more numerous than warm receptors
thermoreceptors
contain sensory cells with ion channels that open in response to membrane distortions
mechanreceptors
monitor muscle length and tension, provide information about the relative position or movement about an animals body parts (include muscle spindles and golgi tendon organs)
proprioceptors
monitor blood pressure, found in carotid sinus and aortic arch, detect tension or stretch in the walls of these blood vessels
baroreceptors
specialized cells with cytoplasmic extensions called stereocilia, send APs when they bend, used for detection of water current, hearing, and balance
hair cells
lateral line system in fish contains _________ in a gelatinous ________, stereocilia are bent and detect currents
hair cells
cupula
perceived as sound, bending of stereocilia
hearing
3 chambers filled with fluid in inner ear, wrapped in a coil
cochlea
has a basilar membrane with hair cells, vibrations of the basilar membrane’s hair cells press the stereocilia against the tectorial membrane, nerve impulses to brain = sound
organ of corti
a few mammals have the ability perceive presence and distance of objects by sound,
echolocation
in vertebrates, the gravity receptors consist of two chambers in the membranous labyrinth
balance
utricle and saccule are hair cells embedded in the otolith membrane, head movement causes the otolithic membrane to move and stereocilia to bend
balance
detect angular acceleration in any direction, ampullae are the chambers, have hair cells in the cupula, acceleration moves the fluid in the canals
semicircular canals
can bind to particular chemicals in extracellular fluid, membrane of sensory neuron becomes depolarized and produces action potentials, sense taste smell and blood composition
chemoreceptor
broken down into five receptor types (sweet, sour, salty, bitter, and umami)
taste
collections of chemosensitive cellsassociated with afferent neurons
taste buds