Sensation
Action Potentials
Reflex Pathway
Synapses/ Neurotransmitters
CNS
100
In general, what is the role of sensory receptors?
Provide information about the internal
and external environment
100
Which ion causes a depolarization? Which one causes a repolarization?
Na+, K+
100
What type of input do afferent neurons carry? Efferent?
Sensory, Motor
100
True or False: Electrical synapses are slower than chemical synapses.
False
100
The limbic system is best characterized as:
A) Brain regions associated with skilled motor movements
B) Brain regions associated with processing all sensory information into a meaningful pattern
C) Brain regions associated with learning, memory, and behavior
C) Brain regions associated with learning, memory, and behavior
200
What is referred pain?
It is the projected perception of pain as a sensation being experienced at a site other than that of the actual injured or diseased tissue.
200
How is the strength of a stimulus encoded by neurons?
(Hint: size, frequency, duration, or positivity/ negativity)
By the frequency of action potentials
200
How long does all the signaling through the sensory pathway, within the central nervous system, and through the motor command pathway take?
Fraction of a second
200
What neurotransmitters would you expect to find active in the synapses during your study sessions devoted to learning the neurotransmitters?
Glutamate
200
What are the 3 main functions of the CSF?
Nourishment, protection, and cushion
300
Visual signals travel on myelinated axons. While most pain signals travel on unmyelinated axons. If you get a paper cut, will you see the cut happen or feel the pain first? Why?
You will experience the visual sensation before the pain sensation. This is because signals travel faster down myelinated axons.
300
Label the parts of the Action Potential Diagram
A) Resting Potential
B) Depolarization
C) Repolarization
D) Hyperpolarization
E) Threshold
300
Does Motor information travel in ascending or descending tracts in the spinal cord? What about Sensory?
Motor: descending
Sensory: ascending
300
What is an example of an inhibitory neurotransmitter? Excitatory transmitter?
Inhibitory: GABA, nicotinic substances
Excitatory: Serotonin, Glutamate
300
What structure would send information for complex muscle movements and unskilled movements?
Extrapyramidal tract
400
Receptors transduce ___________ into a _________ potential which can then cause an ___________ potential which travels through the ________ order neuron.
stimuli ; graded ; action ; first
400
Which is most directly responsible for the falling (repolarizing) phase of the action potential?
The permeability to K + increases greatly while the permeability to Na + decreases.
400
Using a micropipette, a neuroscientist injects an axon with enough Na + ions to move the membrane potential +25mV (from resting).
What happens next?
voltage-gated Na + channels will be triggered to open.
400
A postsynaptic neuron has three presynaptic inputs—from neurons X, Y, and Z.
- Stimulation of neuron X causes the postsynaptic neuron to depolarize by 0.5 mV.
- When X and Y are stimulated simultaneously, the postsynaptic neuron depolarizes by 1 mV.
- When X and Z are stimulated simultaneously,there is no change in the membrane potential of the postsynaptic neuron.
What is most likely true about presynaptic neurons Y and Z? (Hint: what is inhibitory what is excitatory)
Y is excitatory and Z is inhibitory.
400
What are the 3 structures of white matter in the spinal cord?
Lateral, Dorsal, and Ventral Column
500
What are the 5 receptor types? And what are their stimulus'?
Thermoreceptor: temp change
Chemoreceptor: chemical substances
Nociceptor: Pain
Mechanoreceptor: Physical pressure
Photoreceptor: light
500
Which 2 options are needed for the conversion of graded potentials to action potentials:
A) Opening of voltage-gated cation channels
B) A strong enough stimulus to cause the axon hillock to sum the hyperpolarizing graded potentials to reach the threshold
C) A strong enough stimulus to cause the axon hillock to sum the depolarizing graded potentials to reach the threshold
D) Opening of ligand-gated cation channels
C) A strong enough stimulus to cause the axon hillock to sum the depolarizing graded potentials to reach the threshold
D) Opening of ligand-gated cation channels
500
Scenario: You step on a nail. What is the path that the stimulus takes? What causes action?
Receptors transduce environmental stimuli, Afferent neuron carries sensory information towards the spinal cord, Interconnections between neurons integrate signals within the spinal cord, Motor neurons carry efferent information through the ventral root, the targeted effector responds
500
Put these 4 steps from the neurotransmitter release sequence in order:
A) Neurotransmitters diffuse across the synaptic cleft
B) Action potential arrives at presynaptic axon terminal
C) Calcium enters axon terminal
D) Neurotransmitters bind to receptors of the postsynaptic cell
B) Action potential arrives at presynaptic axon terminal
C) Calcium enters axon terminal
A) Neurotransmitters diffuse across the synaptic cleft
D) Neurotransmitters bind to receptors of the postsynaptic cell
500
What are the 4 main lobes of the brain? And what are their main functions?
Frontal: voluntary movements, personality, emotions
Parietal: somatosensory
Occipital: vision
Temporal: hearing