Bio Test 3 Mastering
Drag the labels onto the table to indicate which type(s) of gated ion channels are found in each membrane associated with a chemical synapse. Presynaptic Cell- Presynaptic membrane
Voltage gated Na+ voltage gated K+ voltage gated Ca2+
A physiologist is studying the homeostatic control of blood pH. What type of receptor might be responsible for detecting changes in blood pH?
chemoreceptors
corpus callosum function
communicating between left and right cerebral hemispheres
white matter
contains myelinated axons
ventral root
contains the axons of motor neurons
dorsal root
contains the axons of sensory neurons
gray matter
contains the cell bodies of motor neurons and interneurons
dorsal root ganglion
contains the cell bodies of sensory neurons
Which of the following structures or regions is correctly paired with its function?
corpus callosum: communication between the left and right cerebral cortices
True or false? The potential energy of a membrane potential comes solely from the difference in electrical charge across the membrane.
false
A stimulus has opened the voltage-gated sodium channels in an area of a neuron's plasma membrane. As a result, _____ rushes into the neuron and diffuses to adjacent areas; this in turn results in the _____ in the adjacent areas.
sodium ... opening of voltage-gated sodium channels
which channels operate at resting potential?
sodium potassium pump- moves K+ in and Na+ out non- gated K+ channel- K+ moves out non- gated Na+ channel- Na+ moves in Channels not operating: voltage gated Na+ channel and voltage gated K+ channel
A neuron has a resting potential of about _____ millivolts.
-70
Sensory pathways have four basic functions: sensory reception, transduction, transmission, and perception. How do these functions differ between yourself and a star-nosed mole?
-The number and type of sensory receptors in humans and star-nosed moles differ. -The perception of sensory input by humans and star-nosed moles differs.
The peripheral nervous system (PNS) transmits information to and from the central nervous system (CNS) and plays a role in regulating an animal's movements and internal environment. Determine which of the following statements about the PNS are true.
-The sympathetic division of the PNS prepares the body for physical exertion in stressful situations. -Neurons in the parasympathetic division release neurotransmitters that act on receptors that slow heart rate -Parasympathetic nerves are associated with the cranial and sacral regions of the spinal cord, whereas sympathetic nerves are associated with the thoracic and lumbar regions. -Stimulating the organs of digestion is a parasympathetic response.
central nervous system
-brain and spinal cord -processes information received from sense organs -initiates signals to muscles and organs
peripheral nervous system
-cranial nerves and spinal nerves -carries signals to muscles and organs -carries sensory information toward the spinal cord -afferent and efferent neurons
excitatory postsynaptic potential (EPSP)
-depolarizes the postsynaptic membrane -results from the movement of \rm Na+ ions into the postsynaptic cell -brings the postsynaptic membrane potential closer to threshold
inhibitory postsynaptic potential (IPSP)
-hyperpolarizes the postsynaptic membrane -results from the movement of \rm K+ ions out of the postsynaptic cell -moves the postsynaptic membrane potential farther away from threshold
both central nervous system and peripheral nervous system
-reflexes -enables voluntary locomotion
In humans, control of balance and coordinated movements are associated with increased activity in the ________.
cerebellum
pain withdrawal reflex
1. a painful stimulus activates a pain sensory neuron 2. the signal is transmitted by the pain sensory neuron to the spinal cord 3. the signal is transmitted to an interneuron and then to a motor neuron 4. the motor neuron stimulates the effector muscle 5. the effector muscles cause a withdrawal response 6. an axon from the interneuron relays sensory information to the brain
Which statement correctly describes what causes the second voltage-gated Na+ channel to open?
After the first channel opens, the movement of many types of ions (both inside and outside the cell) alters the distribution of charges near the second channel, causing it to open.
Identify the correct statement(s) about sensory receptors.
Foods taste spicy when they activate the same sensory receptors that high temperatures activate. Mechanoreceptors detect sound.
Rank the axons from slowest to fastest conduction speed. If two axons have the same conduction speed, place one on top of the other.
For non-myelinated axons, the larger the diameter of the axon, the faster the conduction speed of an action potential. However, even the smallest myelinated axons are much faster than the largest non-myelinated axons (the squid axon, for example).
If a person suffered a stroke which damaged brain region B, what might be the expected outcome? (cerebrum)
Higher-level integration of sensory inputs and motor outputs would be impaired.
Partial or complete loss of hearing (deafness) can be caused by damage to the _____. I) axons of the neurons associated with each hair cell that carry information to the brain II) hair cells (the sensory receptors) in the cochlea III) tympanic membrane, or eardrum
I, II, and III
In a mammalian visual system, visual information is integrated at ________. I) the lens II) the retina III) the optic nerve IV) the visual cortex
II and IV
Resting neurons are most permeable to which of the following ions?
K+
voltage gated channels in falling phase
Na+ channels close K+ channels open
voltage gated channels undershoot
Na+ channels close K+ channels open
voltage gated channels in resting potential
Na+ channels closed K+ channels closed
voltage gated channels in rising phase
Na+ channels open K+ channels close
The round window ________. I) dampens fluid vibrations II) collects sound pressure waves III) detects the frequency of sounds
only I
What type of cell makes up the myelin sheath of a motor neuron?
Schwann Cells
How is an action potential propagated down an axon after voltage-gated sodium channels open in a region of the neuron's membrane?
Sodium ions enter the neuron and diffuse to adjacent areas, resulting in the opening of voltage-gated sodium channels farther down the axon.
Which event triggers the creation of an action potential?
The membrane depolarizes above a certain threshold potential.
What behavior is observed if the voltage across a neuronal membrane is set to -20 mV?
The sodium channel opens, and Na+ ions flow in.
Which channel maintains the concentration gradients of ions across a neuronal membrane?
The sodium-potassium pump moving Na+ ions out and K+ ions in.
Which of the following statements about action potentials in a given neuron is false?
They are propagated down the length of the dendrite
Drag the labels onto the table to indicate which type(s) of gated ion channels are found in each membrane associated with a chemical synapse. Presynaptic Cell- Synaptic Terminal
Voltage gated Na+ voltage gated K+
Which term describes an electrical signal generated by neurons?
action potential
The structure of the mammalian middle ear is adapted to convert ________.
air pressure waves to fluid pressure waves
Which of these causes the release of neurotransmitter molecules?
an action potential reaching the end of the axon
semicircular canals
arranged in 3 spatial planes, detect angular movements of the head. the swelling at the base of each canal contains a cluster of hair cells.
A nerve impulse moves away from a neuron's cell body along _____.
axon
An action potential moves along a(n) _____.
axon
location of voltage gated channels
axon
Where in the neuron do action potentials begin?
axon hillock
Control of respiration and circulation are associated with the ________.
brain stem
How does the movement of K+ ions through the artificial channel affect the membrane potential?
causes a hyperpolarization
A neuron's nucleus is located in its _____.
cell body
A nerve impulse moves toward a neuron's cell body along _____.
dendrites
Location of ligand-gated channels
dendrites and soma
After eating a large meal, which branch of your nervous system is activated?
enteric
True or false? Action potentials travel in only one direction down an axon because potassium channels in the neuron are refractory and cannot be activated for a short time after they open and close.
false Action potentials travel in only one direction down an axon because sodium channels in the neuron are refractory.
Which of the following shows a brain structure correctly paired with one of its primary functions?
frontal lobe: decision making
The blind spot in the human retina is the location that has the collected axons of _____.
ganglion cells
Which of the following sensory receptors is correctly paired with its category?
hair cell: mechanoreceptor
Artificial electrical stimulation of a human's capsaicin-sensitive neurons would likely produce the sensation of _____.
hot temperature
Which of the following characteristics determines when the refractory period ends?
how long it takes for the voltage-gated Na+ channels to reactivate at the end of an action potential
The transmission first triggers the _____.
opening of voltage-gated sodium channels and the diffusion of sodium ions into the neuron
Which of the following terms describes how a neuronal membrane's potential is altered in the presence of inhibitory signals?
hyperpolarization
Does the membrane potential promote or impede the movement of K+ ions through the artificial channel?
impede
After narrowly escaping a mountain lion attack, which of the following reactions would your nervous system initiate?
increased heartbeat
both EPSP and IPSP
is a graded potential
Drag the labels onto the table to indicate which type(s) of gated ion channels are found in each membrane associated with a chemical synapse. Postsynaptic cell- postsynaptic membrane
ligand- gated
Emotion, motivation, olfaction, behavior, and memory, in humans, are mediated by the _____.
limbic system
cerebellum function
maintaining balance while walking
Sensory transduction in the auditory system is much like transduction of _____.
mechanosensory stimuli
Increases and decreases of the heart rate result from changes in the activity of the _____.
medulla oblongata
Which term describes the difference in electrical charge across a membrane?
membrane potential
What structures would neurobiologists look for if they are interested in determining if an animal can see in color?
opsin
what is the cascade of events that follow? membrane potential reaches threshold
membrane potential reaches threshold-> many voltage- gated Na+ channels open-> Na+ ions rush into the cell-> membrane potential rises (depolarizes) rapidly
In mammals, the eardrum transmits sound waves to three small bones, which transmit the waves to fluid waves within the cochlea. Where are the three small bones located?
middle ear
Dizziness is a perceived sensation that can occur when _____.
moving fluid in the semicircular canals encounters a stationary cupula
Axons insulated by a(n) _____ are able to conduct impulses faster than those not so insulated.
myelin sheath
Which structure is not part of a neuron?
myelin sheath
Tastes and smells are distinct kinds of environmental information where ________.
neural projections from taste receptors reach different parts of the brain than the neural projections from olfactory receptors
An impulse relayed along a myelinated axon "jumps" from _____ to _____.
node of Ranvier ... node of Ranvier
Drag the labels onto the table to indicate which type(s) of gated ion channels are found in each membrane associated with a chemical synapse. Postsynaptic cell- plasma membrane of cell body
none
Short-term and long-term memory are related but have important differences. Short-term memory ________.
occurs within the hippocampus and is essential for acquiring new long-term memories within the cerebral cortex
Most of the chemosensory neurons arising in the nasal cavity have axonal projections that terminate in the _____.
olfactory bulb
Which of the following sensory receptors is incorrectly paired with its category?
olfactory receptor: electromagnetic receptor
in what direction will the K+ ions move through the artificial channel?
out of the cell
Which channel is mainly responsible for the resting potential of a neuron?
potassium leak channel
Does the K+ concentration gradient promote or impede the movement of K+ ions through the artificial channel?
promote
The knee-jerk reflex has sensory neurons arising in the _____, interneurons in the _____, and efferent neurons that stimulate contraction in the _____.
quadriceps muscle ... spinal cord ... quadriceps muscle
brainstem function
regulating a person's resting heart rate
Sensory transduction of light in the vertebrate retina is accomplished by _____.
rods and cones
diencephalon function
sending signals from the senses to the appropriate brain region
A thermosensory neuron in the skin converts heat energy to nerve impulses via a conversion called _____.
sensory transduction
The correct sequence of sensory processing is ________.
stimulus reception → sensory transduction → sensory perception → sensory adaptation
The space between an axon of one neuron and the dendrite of another neuron is called a(n) _____.
synaptic cleft
What part of a neuron relays signals from one neuron to another neuron or to an effector?
synaptic terminal
Neurons store neurotransmitter molecules in vesicles located within _____.
synaptic terminals
utricle (vertical) and saccule (horizontal)
tell the brain which way is up and inform it of the body's position of linear acceleration
Hair cells in the vertebrate ear are responsible for transducing sound pressure waves. Ion channels in the hair cell membrane open when _____.
the membrane is distorted mechanically
In a simple synapse, neurotransmitter chemicals are received by _____
the postsynaptic membrane
At rest, which of these plays a role in establishing the charge differential across a neuron's plasma membrane?
the sodium-potassium pump moving sodium ions out of the neuron and potassium ions into the neuron
Drag the labels onto the table to indicate which type(s) of gated ion channels are found in each membrane associated with a chemical synapse. postsynaptic cell- axon hillock
voltage gated Na+ voltage gated K+
cerebrum function
working a crossword puzzle
Drag the labels onto the flowchart to indicate the sequence of events that occurs in the presynaptic cell (orange background) and the postsynaptic cell (blue background) after an action potential reaches a chemical synapse.
~Presynaptic Cell -action potential enter enters the presynaptic membrane -Ca2+ channels in presynaptic membrane open briefly -Ca2+ ions enter presynaptic cell -neurotransmitter- containing vesicles fuse with presynaptic membrane -neurotransmitter released into presynaptic cleft ~postsynaptic cell -neurotransmitter binds to ligand- gated channels in postsynaptic membrane; channels open -neurotransmitter degraded or removed from cleft; ligand- gated ion channels close
