10: Organisms Sense Their Environment Flashcards
Module 2, Lesson 4
____ are receptors that detect stimuli inside the body.
Interoceptors
____ are receptors that detect stimuli outside the body.
Exteroceptors
List the three main categories of receptors.
- Mechanoreceptors
- Chemoreceptors
- Electromagnetic receptors
____ detect mechanical stimuli.
Mechanoreceptors
List five examples of stimuli detected by mechanoreceptors.
- Touch
- Pain
- Pressure
- Hearing
- Balance
____ are stimuli with receptors located in a specialized organ.
Special senses
List five special senses.
- Hearing
- Balance
- Taste
- Smell
- Vision
____ detect chemical stimuli.
Chemoreceptors
List three examples of stimuli detected by chemoreceptors.
- Taste
- Smell
- pH
____ detect electromagnetic energy.
Electromagnetic receptors
List two types of stimuli detected by electromagnetic receptors.
- Vision
- Heat
List the four main steps in conveying sensory information.
- Stimulation
- Transduction
- Transmission
- Interpretation
____ occurs when a stimulus impinges on a receptor.
Stimulation
____ occurs when the stimulus’ energy is converted to graded potentials in the sensory neuron.
Transduction
____ occurs when graded potentials are converted to action potentials, then conveyed to the central nervous system.
Transmission
____ occurs when the brain forms a perception of a stimulus.
Interpretation
A ____ is similar to an EPSP, but is caused by a stimulus instead of another neuron.
Receptor potential
True or false:
Receptor potentials are usually hyperpolarizations.
False
They are usually depolarizations.
A more intense stimulus results in a larger…
Depolarization
____ gated ion channels open when the channel is touched.
Stimulus/mechanically
The intensity of a stimulus is communicated by the…
Frequency of action potentials
List seven major classes of mechanoreceptors.
- Nociceptors
- Thermoreceptors
- Touch receptors
- Proprioceptors
- Baroreceptors
- Sound receptors
- Motion receptors
Several mechanoreceptors use ____ ion channels, a special type of stimulus-gated ion channels.
Transient receptor potential
(TRP)
TRP ion channels respond to…
Temperature
____ are receptors that detect actual or potential tissue damage and noxious substances.
Nociceptors
____ have free nerve endings spread throughout the body.
Nociceptors
Nociceptors are most concentrated in areas where…
Injury is most likely to occur
____ are receptors that detect temperature changes.
Thermoreceptors
True or false:
There are separate receptors for increases and decreases in temperature.
True
____ are found in the skin and hypothalamus.
Thermoreceptors
Which two types of mechanoreceptors contain TRP ion channels?
- Nociceptors
- Thermoreceptors
Mechanoreceptors for ____ contain multiple different types of receptors located at different depths in the skin and in different kinds of skin.
Touch
List five different types of mechanoreceptors for touch.
- Hair follicle receptors
- Meissner corpuscles
- Pacinian corpuscles
- Ruffini corpuscles
- Merkel’s disks
____ monitor position and movement of the body.
Proprioceptors
Proprioceptors located in muscles are called…
Muscle spindles
Proprioceptors located in tendons are called…
Golgi tendon organs
____ monitor blood pressure.
Baroreceptors
List three areas in which baroreceptors are found.
- Carotid sinus
- Arteries that supply blood tot the brain
- Aortic arch
____ are hearing structures in acquatic animals, such as fish.
Otoliths
____ are hearing structures in terrestrial animals.
Ears
List the three main divisions of the human ear.
- Outer ear
- Middle ear
- Inner ear
In humans, the ____ contains the receptors for sound waves.
Inner ear
In humans, the ____ converts sound waves into motion of solid structures.
Outer and middle ear
Sound waves strike the ____ and transfer sound to bones in the middle ear.
Tympanic membrane
The last bone in the middle ear vibrates the ____ which transfers sound to the inner ear.
Oval structure
The ____ is a complex, spiral-shaped, fluid-filled structure in the inner ear.
Cochlea
In the inner ear, sound waves are converted to ____ that travel through the cochlear duct.
Pressure waves
Pressure waves travel through the cochlear duct and eventually strike the…
Organ of corti
In the organ of corti, pressure waves vibrate the…
Basilar membrane
____ are embedded in the basilar membrane.
Sensory hair cells
The hair cells embedded in the basilar membrane have special cilia called…
Stereocilia
The tips of the stereocilia are embedded in the…
Tectorial membrane
The bending of the stereocilia relative to the tectorial membrane is transduced into…
Receptor potentials
The fibers at the ____ of the cochlea are long and flexible.
Apex
The fibers at the ____ of the cochlea are short and tight.
Base
____ causes the basilar membrane to vibrate near the apex.
Low-frequency sound
____ causes the basilar membrane to vibrate near the base.
High-frequency sound
Invertebrates detect gravity and motion using…
Statocysts
Vertebrates detect gravity and motion using special structures in their…
Ears
In vertebrates, the ____ detects horizontal motion.
Utricle
In vertebrates, the ____ detects vertical motion.
Saccule
Motion causes a gelatinous membrane in the ear to move with the help of crystals called…
Otoliths
Movement of the gelatinous membrane causes the cilia to bend, and the bending is transduced into…
An impulse sent to the brain
In vertebrates, ____ detect angular motion.
Semicircular canals
In the semicircular canals, when angular motion occurs a wedge of gelatinous membrane called the ____ is distorted by movement of fluid.
Cupula
____ are swollen chambers that the end of the semicircular canals that contain cilia, hair cells, and cupulae.
Ampullae
List three types of chemoreceptors.
- Taste receptors
- Smell receptors
- pH receptors
____ is the perception of taste.
Gustation
In terrestrial vertebrates, taste is sensed using…
Taste buds on the tongue and in the oral cavity
True or false:
Sensory neurons in taste buds respond differently depending on the food’s properties.
True
In ____ food, sodium enters directly into ion channels to depolarize receptors.
Salty
In ____ food, protons enter ion channels to depolarize receptors.
Sour
In ____ food, chemicals in the food interact with G-protein coupled receptors.
Sweet, bitter, and umami
The chemoreceptors for smell are found in the…
Nasal mucosa of the nasal passage
Sensory neurons involved in smell have cilia on their dendrites that extend into the…
Nasal passage
The axons of sensory neurons involved in smell extend into the…
Cerebral cortex
True or false:
In many terrestrial vertebrates, smell receptors can detect just one molecule of a chemical.
True
____ chemoreceptors monitor blood pH.
Peripheral
The chemoreceptors that monitor blood pH are located in the…
Aorta and carotid bodies
____ chemoreceptors monitor cerebrospinal fluid pH.
Central
The chemoreceptors that monitor cerebrospinal fluid pH are located in the…
Medulla oblangata
Increased levels of CO2 in the blood causes a(n) ____ in blood pH.
Decrease
____ are electromagnetic receptors that detect light to create visual perceptions.
Photoreceptors
True or false:
Many invertebrates have the ability to form a visual image.
False
Many invertebrates have ____ that detect light, enabling the animal to avoid or seek light.
Eye spots
Only ____ phyla have evolved complex eyes.
Four
In vertebrate eyes, light enters and is focused through the…
Cornea and lens
The amount of light allowed into the eye is determined by the size of an opening in the iris called the…
Pupil
The ____ of the eye can change shape to allow the image to focus properly.
Lens
A major difference between vertebrate and invertebrate eyes is that…
Their retinal layers are in opposite orders
In ____ eyes, light immediately strikes the photopigments.
Invertebrate
True or false:
Invertebrate eyes do not have a blind spot.
True
The surface on the back of the eye is called the…
Retina
In ____ eyes, the photoreceptive cells are in the rearmost layer of the retina.
Vertebrate
The furthest back layer of the retina, Layer 1, contains the…
Rods and cones
____ are photoreceptive cells responsible for detecting light and dark.
Rods
____ are photoreceptor cells responsible for detecting color and allowing for sharp images in bright light.
Cones
The central layer of the retina, Layer 2, contains the…
Bipolar cells
The ____ receive sensory information from the photoreceptive cells.
Bipolar cells
The frontmost layer of the retina, Layer 3, contains the…
Ganglion cells
____ send sensory information to the brain.
Ganglion cells
In the eye, axons are bundled together and sent through the ____ to reach the brain.
Retina
True or false:
Vertebrate eyes do not have a blind spot.
False
The optical nerve passing through the retina creates one.
Sensory transduction of ____ and ____ works differently than in other receptors.
Dark and light
In photoreceptors, darkness results in…
Depolarization
When an animal is in darkness, sodium ions enter the cell and send an ____ signal to the bipolar cells.
Inhibitory
In photoreceptors, light causes…
Hyperpolarization
When an animal is in the light, sodium channels close, which enables the bipolar cells to send a ____ signal to the ganglion cells.
Stimulatory
List three examples of uncommon senses.
- Sensing infrared wavelengths
- Sensing electrical currents
- Sensing magnetic fields
____ can sense infrared wavelengths using special pit organs.
Snakes
Some ____ can sense electrical currents.
Fish
Various organisms, but not humans, have the ability to sense…
Magnetic fields
