Chapter 36 Sensory Systems Flashcards
Which type of sensory receptor activates G proteins that leads to the production of second messengers.
metabotropic receptors
If a person is unable to maintain their balance and is dizzy, which structure is the most likely candidate for these symptoms?
Vestibular System
Which behavior results from the adaptation of sensory cells?
not smelling something after being in its presence for a while
The ear can distinguish different sound frequencies because different parts of the ____ respond differently to the different frequencies.
basilar membrane
Drugs that inhibit G proteins will affect ___.
vision and smell
True or False: The retina is the location of photoreceptor cells.
True
Smelling baking cookies triggers a(n) ___.
chemoreceptor
What is the name of the structure that enables you to hear different pitches (frequencies)?
basilar membrane
Which of the following senses requires the activation of mechanoreceptors?
hearing
The sound of an alarm clock in the morning triggers a(n) ____ in the sleeper.
mechanoreceptor
Photoreceptors in humans are found in the ____.
retina
Olfaction involves which type of tropic receptor?
metabotropic receptor
What is another word for sensory receptors?
sensors
What do sensory receptor cells do?
convert physical and chemical stimuli into neuronal signals
Where do the neuronal signals travel to for processing?
central nervous system
What are the 6 types of sensory receptors?
- chemoreceptors
- mechanoreceptors
- photoreceptors
- electroreceptors
- magnetoreceptors
- thermoreceptors
Chemoreceptors
include taste, pH, blood oxygen levels, etc.
Mechanoreceptors
include touch, heairng, blood pressure
Photoreceptors
sense light wavelenghts
Electroreceptors
generate and detect electric fields
Magnetoreceptors
sense earth’s magnetic field
Thermoreceptor
sense changes in temperature
Do all senses have similar pathways?
YES
What happens after a signal is received in a sensory system pathway?
the cell converts a stimulus into an intracellular signal (signal transduction)
What happens after signal transduction in a sensory system pathway?
The signal is amplified by enzymes that create second messengers
What happens after a signal is amplified in sensory systems?
The signal is sent to the integrating center by the nervous system
Perception of signals occurs at ___.
integrating center
What type of signal is the sensory information converted into?
electrical signal
What are the two types of tropic receptors?
Metabotropic and Ionotropic
Ionotropic Receptors
ion channels or direct opening of ion channels
3 Types of Ionotropic Receptors
- mechanoreceptor
- thermoreceptor
- electroreceptor
How does a mechanoreceptor open a channel?
pressure
How does a thermoreceptor open a channel?
heat
How does an electroreceptor open a channel?
electric charge
Metabotropic receptors
influence ion channels indirectly through G proteins and second messengers
2 Types of Metabotropic Receptors
- chemoreceptor
- photoreceptor
Olfaction
sense of smell
What type of receptor does the sense of smell rely on?
chemoreceptors
Where are the bipolar neurons in vertebrates for sense of smell?
in the epithelial tissue on top of the nasal cavity
Sensory Adaptation
sensory cells give smaller and smaller responses
What type of tropic receptor does smell rely on?
Metabotropic
Gustaion
sense of taste
What receptor does sense of taste rely on?
chemoreceptor
Where are chemoreceptors found in the tongue?
tastebuds
Where are tastebuds found?
papilla of tongue
Where is microvilli found in the tongue?
sensory cells
Where do molecules bind in taste?
receptors on microvilli
What do sensory cells do in the tongue?
release neurotransmitters that stimulates sensory neurons
5 Tastes
- salty
- sweet
- sour
- bitter
- umami
Do cells of tastebuds produce action potentials?
YES
Are metabotropic or ionotropic receptors found in taste?
both
Outer Ear
tympanic membrane at the end of the ear canal
Characteristics of the Middle Ear
- has 3 bones
- contains eustachian tube
3 Bones in the Middle Ear
- malleus
- incus
- stapes
What is another word for bones in the ear?
ossicles
Eustachian Tube
opens to throat from ear
Inner Ear
location of cochlea and vestibular system
Does the tympanic membrane in the ear vibrate?
YES
What do the 3 bones in the middle ear vibrate against?
the oval window
Characterisitcs of the Cochlea
- coiled structure
- has sensory cells responsible for heaing
Characteristics of Semicircular Canals
- responsible for equilibrium
- have hair cells
What structure is responsible for hearing?
cochlea
What type of tropic receptors are hair cells?
ionotropic receptors
Is the basilar membrane above or below the tectorial membrane?
below
Does the basilar membrane release neurotransmitters?
YES
What do sound waves create?
pressure waves in cochlear canals
Semicircular Canals sense…
orientation (turning of head)
Vestibule is a chamber with ___.
the utricle and saccule
Stereocilia of hair cells are embedded in…
gelatinous membrane
Vestibule detects…
linear acceleration
Sclera
white part of the eye
Iris
controls the amount of light that is entering the eye
Pupil
opening of iris
Lens
focuses light onto retina
Retina
contains photoreceptors
Blind Spot
- where the nerve leaves
- no photoreceptors
Are hair cells in the ear involved with equilibrium?
YES
What receptor does vision use?
photoreceptors
What do rods and cones respond to?
light
Light
electromagnetic waves
Does light need a medium to travel?
NO
Rods
detects dim light and grays
Cones
detects bright lights and colors
Are cones more sensitive than rods?
NO
What are photopigments made of?
protein and retinal
Rhodopsin
photopigment in rods
What happens when light hits the retinal?
- will change conformation
- causes opsin (protein) to change conformation
- activates g protein
Are metabotropic or ionotropic receptors responsible for light?
metabotropic
You walk into an Italian restaurant, and when you first arrive the smell of pizza, pasta and bread is really strong, but after 10-15 minutes you don’t notice it. What is this process called?
sensory adaptation
Which structure in the inner ear is responsible for detecting different pitches?
basilar membrane
Photoreceptors are a type of ____.
metabotropic receptors
Which photoreceptors function during bright light and enable you to see colors?
cones
Which type of receptor involves G proteins and second messengers in a sensory receptor pathway?
metabotropic receptors
Put the following events in the correct order that they occur during sensory perception in a vertebrate.
1. Action potentials are produced in neurons that transmit information to the brain.
2. Receptor proteins in the cell membranes of sensory receptor cells bind to (or are affected by) an external signal.
3. Perception of the signal occurs.
4. Amplification of the signal occurs within the sensory cell.
5. Signal transduction occurs.
2, 5, 4, 1, 3
True or False: Hair cells are metabotropic receptors.
False
When sensory receptor cells recognize a particular stimulus (e.g., light, chemicals) they will transduce that external incoming stimulus ____.
into an intracellular signal
