Unit 1
Unit 2
Unit 3
Unit 4
Xtra
100
Patient with hippocampal lesions and an inability to form new memories
Who is Henry Molaison (Patient HM)?
100
The probability of release of a synapse can be altered by changing the concentration of _____, with _____ probability synapses having a smaller releasable vesicle pool and a ____ PPR:
What is: Ca2+, low, large (above 1)
100
Describe the overall molecular pathway for ON bipolar cells in the light/dark. Is it the same for OFF bipolar cells?
What is:
Dark: In ON cells, which have metabotropic receptors, glutamate (present in the dark since photoreceptors depolarize in the dark) activates mGluR6, a GPCR, and this inhibits TRPM1 (ion channel).
Light: glutamate is not present, so TRPM1 is not inhibited, so the channel is open and the cell depolarizes
No - OFF bipolar cells have ionotropic receptors where glutamate helps open AMPA channels
100
Why is the speed of the pain and touch pathways different?
What is: The fibers responsible for pain (A-delta and C) are thinner in diameter and less myelinated (C fibers are not myelinated) than the fibers responsible for touch (A-beta)
100
Based on Ohm’s Law, how is current affected if resistance is increased and voltage is kept constant?
What is: current would decrease (V=IR)
200
Scientist that created the Reticular Theorem, and what does it state?
Who is Golgi?
The nervous system is comprised of a single continuous network.
200
What type of experiment produces each graph?
A)
B)
C)
D)
What is:
A) Extracellular AP's B) Single Channel Currents C) Whole-Cell Current Clamp D) Whole-Cell Voltage clamp
200
What are the functions of the two major areas in the ventral stream of visual processing?
What is:
V4: shape and color perception
Area IT: processing of complex objects (e.g., faces)
200
Location in nervous system where touch and motor pathways cross side of body
What is:
Medulla
200
How does the activation of the periaqueductal gray (PAG) region of the brain contribute to the analgesic effects of opioids?
What is: activation of the PAG region leads to the release of endorphins (norephinephring and endogenous opiods) from downstream brainstem structures, which suppress pain signals throughout the body
300
Increasing the extracellular concentration of Sodium would do what to the resting membrane potential:
What is: not much :/
300
A nerve cell has a resting membrane potential of -70mV and a threshold of -55mV. The reversal potential for one type of synapse on this neuron is -60mV and it allows the flow of cations. Is this synapse excitatory or inhibitory?
What is: Inhibitory
It will depolarize the cell but prevent it from reaching -55mV (threshold) since its reversal potential is more negative (-60mV). An excitatory synapse is one that will increase the likelihood of cell reaching the threshold
300
Name the two types of photoreceptors. How are they different?
What is: Rods and cones. Rods are more sensitive to light; cones are sensitive to different wavelengths of light. There are no rods in the fovea.
300
Which sensory receptors are fast adapting? What does this mean? What are the differences between the two fast adapting sensory receptors?
What is: Meissner and Pacinian. This means they are good for detecting changes in sensation and vibrations. Meissner corpuscles are small and respond best to light touch low frequency vibrations while Pacinian corpuscles are larger and respond best to pressure and high frequency vibrations.
300
Is the presence of Calcium necessary for induction, expression, and maintenance of LTP? Explain.
What is: No, calcium flowing through NMDA receptors is necessary to induce LTP, CaMKII activation is necessary for LTP expression, but gene expression and protein translation and long lasting CamKII activity are the main mechanisms for LTP maintenance.
400
The stage of the action potential where driving force for sodium is lowest
What is action potential peak?
400
The shared mechanisms of hippocampal LTP and LTD
What are:
NMDAR activation and calcium influx
400
Location where orientation selectivity starts in the visual system
What are V1 cells? or What is the primary visual cortex?
400
Describe a key difference between the structure and role of intrafusal muscle fibers vs intrafusal muscle fibers.
What is: Intrafusal muscle fibers are within the muscle spindles; they are responsible for detecting changes in muscle length and change via sensory receptors with proprioceptive feedback. Extrafusal muscle fibers are responsible for generating force and movement - they contract in response to motor neuron stimulation and generate muscle movement.
400
The main excitatory neurotransmitter at the neuromuscular junction is:
The main excitatory neurotransmitter in the brain is:
The main inhibitory neurotransmitter in the brain is:
What is: acetylcholine, glutamate, GABA
500
Besides voltage gated potassium channel activation, this channel property is integral to the repolarization phase of the action potential
What is: sodium channel inactivation
500
Why are NMDA receptors "coincidence detectors"?
What is: They require both Glutamate and depolarization
500
Describe the retinal rhodopsin pathway when light is present
What is:
1. Light activates (bleaches) rhodopsin.
2. Transducin, the G-protein, is stimulated.
3. Phosphodiesterase (PDE), the effector enzyme, is activated.
4. PDE activity reduces the cGMP level.
5. cGMP-gated cation channels close, and the cell membrane hyperpolarizes
500
Neuronal mechanisms of increasing muscle force
What are increasing firing rate and recruiting additional motor units?
500
Technique in neuroscience that uses light to modulate electrical activity in neurons.
What is optogenetics?