chapter 27 the senses Flashcards
the [blank] connect the nervous system to the outside world
senses
general senses
all over the body
touch, temperature, pain
special senses
restricted to the head
hearing and equilibrium, vision, smell, and taste
sensory receptors
cells found in sense organs that translate stimuli into electrical signals (transduction)
transduction
a process that translates stimuli into electrical signals
type of receptors in skin
mechanoreceptor and thermoreceptor
where are pain receptors located?
everywhere except for the brain
the stretching of muscles and ligaments is the stimulus for this type of receptor
proprioceptor
the nasal cavity, mouth and tongue have this type of receptor
chemoreceptor
type of receptor in eyes
photoreceptor
type of receptor in ears?
mechanoreceptor
During transduction, sensory receptor cells undergo changes in the membrane potential, cueing…
receptor potentials
action potentials carry…
information from the sensory receptors to the brain
If the receptor potential reaches threshold…
an action potential occurs in the sensory receptor
sensation
the raw input from the peripheral nervous system that arrives at the central nervous system
perception
the brain’s interpretation of a sensation
Under constant stimulation, a sensory receptor generates [blank] action potentials, leading to [blank]
fewer
sensory adaptation
what happens during sensory adaptation
sensations cease to reach the central nervous system
receptor that responds to temperature
thermoreceptor
mechanoreceptor
respond to physical stimuli such as sound or touch
pain receptors
respond to physical damage to body tissues
why can the brain receive pain, touch, and heat at the same time?
because pain, touch, and heat have unique receptors
receptor to sense the position of body parts
proprioceptor
chemoreceptors respond to …
chemicals
olfaction
the sense of smell
detects chemicals in the air
Inside of the nose is lined with [blank] receptor cells. Each has one type of [blank] receptor, which responds to only a [blank] odorant molecules
olfactory
protein
few
how does the brain receive information about smell
each olfactory receptor synapses with olfactory bulb neurons, which send signals to the olfactory cortex of the brain
gustation
the sense of taste, which allows us to detect chemicals only at close range
papillae on the [blank] house [blank]
tongue
taste buds
each taste bud has several [blank]
taste receptor cells
how does the brain receive information about taste
taste receptor cells respond to dissolved food molecules and relay messages to sensory nerves leading to the brain
the sense of vision detects…
light
how does vision work?
specialized cells in the eye send signals to the brain, which interprets those signals as an image
how light enters and travels through the eye
light passes through the cornea and aqueous humor to the pupil
the lens bends the light, which converges at the retina
pupil
the opening in the iris that allows light into the eye
how do glasses work?
they change the path of light
thousands of photoreceptors line the back of the [blank]
retina
rod cells
provide black-and-white vision in dim light
cone cells
detect color
pigment molecules are found in [blank] and absorb…
rods and cones
light
signals pass through the optic nerves to the [blank] in the back of the brain
visual cortex
forms that invertebrate eyes can take
eye cups, compound eyes, and single-lens eye
eye cups
distinguish light intensity and direction
compound eyes
distinguish shapes; “mosaic vision”
single-lens eye
forms distinct images
how does hearing work?
sensory receptors in the inner ear translate vibrations in the air into action potentials
vibrations in the air are funneled through the [blank] toward the [blank]
auditory canal
eardrum
eardrum vibrations vibrate three small middle ear bones called…
the hammer, anvil, and stirrup
the vibrating stirrup moves the [blank], which connects the…
oval window
middle ear to the inner ear
transduction occurs at cells in the [blank] of the inner ear
cochlea
vibrations move like [blank] through the [blank] filled chambers of the cochlea
waves
fluid
hair cells detect [blank] and are embedded in…
vibrations
the basilar membrane of the cochlea
the movement of the cochlear fluid bends [blank] on hair cells, producing [blank].
cilia
receptor potentials
auditory nerve
transmits signals to the brain
the location and intensity of hair cell stimulation does not communicate information about the sound to the brain
true or false
false
lower-pitched sounds do not vibrate hair cells farther into the cochlea than do higher-pitched sounds
true or false?
false
do louder sounds stimulate more or less hair cells than quieter sounds
more
does the inner ear provide the sense of equilibrium?
yes
Near the cochlea in the inner ear is the [blank]. It consists of two pouches and three semicircular canals
vestibular apparatus
fluid in the pouches and semicircular canals of the vestibular apparatus moves…
the cilia of hair cells
does the fluid in vestibular apparatus move as the body moves?
yes
utricle
pouch in the vestibular apparatus
fluid in the pouch moves when the head accelerates horizontally
saccule
pouch in the vestibular apparatus
the fluid in the pouch moves when the head accelerates vertically
what do the semicircular canals detect and how are they oriented
they detect whether the head is rotating
they are oriented in different directions
do senses help maintain homeostasis?
yes
