What notion was displaced by the
concept of nerves being described as wires?
Nerves are channels that communicate with the brain by movement of fluids
The main site of protein synthesis
(complete with ribosomes and rough ER) in the neuron is:
Soma
The “Neuron Doctrine” that
neurons are the fundamental functional unit of the nervous system,
was illuminated primarily by which of the following?
a) Santiago Ramon y Cajal's use of the Golgi stain to demonstrate neurons are not continuous.
The order of events in an action potential
a) Sodium-potassium pumps maintain equilibrium potential against concentration gradient
b) Voltage-gated sodium channels are open and there is a massive influx of sodium
c) Voltage-gated sodium channels are inactivated
d) Potassium efflux predominates
e) Hyperpolarization occurs
Why is it important for glial cells and/or transporter molecules to deliver excess neurotransmitter from the synaptic cleft back into the presynaptic neuron?
a) because the excess neurotransmitter might desensitize the postsynaptic density to important glial cells
Why do action potential travel only in one direction?
a) The membrane just behind the action potential is refractory due to inactivated sodium channels
Saltatory conduction of nervous impulses is characterized by which of the following:
E) All of the above
Why are neuromuscular junctions such reliable synapses?
a) because the axon terminal is so large; the presynaptic terminal contains a large number of active zones, and the motor end plate contains a series of shallow folds
Which of the following is atechnique that utilizes antibodies conjugated with a visible marker to localize neurotransmitter (and/or enzymes involved in their synthesis) within the brain?
a) Immunocytochemistry
Neurons comprise two types of processes: axons and dendrites. What is the major difference between the two?
a) dendrites receive incoming signals from other neurons while axons carry the output of the neurons
Membrane differentiations demarcate the syaptic cleft. Which component of the membrane differentiation contains neurotransmitter receptors?
a) Postsynaptic density
The process that facilitates transport of molecules from soma to axon terminal is called ______, and relies heavily on the activity of a molecule called ________.
C) anterograde transport, kinesin
What is the meaning of an ion's equilibrium potential?
a) Electrical potential difference that exactly balances an ionic concentration gradient
The undershoot phase of the action potential is responsible for a period called the ______ during which subsequent action potentials are inhibited but not impossible to achieve.
a) Relative refractory period
What is meant by the action potential threshold?
a) Critical level of depolarization required to trigger an action potential
Which of the following channels in the active zones of the synaptic terminal open when the membrane depolarizes and causes the release of the synaptic vessicles
C) voltage-gated calcium channels
Secretory granules contain _____, while synaptic vessicles contain _______.
A) peptide transmitters, amino acid and amine transmitters
What is a synaptic integration?
B) a process by which multiple synaptic potentials combine within one postsynaptic neuron
Which factors influence the selectivity of ion channels?
E) all of the above
The Nernst equation gives quantitative value for the equilibrium potential of a specific ion. When would the equilibrium potential for K+ be equal to 0mV?
a) When [K+]0 = [K+]i
Brain slices are bathed in a concentrated K+ solution to stimulate neurotransmitter release. Why must calcium ions also be present in the bathing solution?
a) Transmitter release requires the entry of calcium into the axon terminal
Which chemical structure unifies
catecholaminergic neurons?
a) catechol
S.B., a 12 year old girl, has significant gait abnormalities resulting from cerebral palsy. When ambulating, she walks on her toes and exhibits a scissor gait, with her legs strongly adducted with each step. She does not show significant improvement with physical therapy. Her doctors now want to inject a small amount of botulinum toxin into the muscles of both legs in an effort to reduce involuntary muscle activity and improve gait. A small amount of botox would reduce involuntary muscle
activity by:
A) decreasing acetylcholine release at the NMJ
Which of the following differentiates the AMPA and the NMDA glutamate-gated channels?
D) all of the above
What is synaptic integration?
A. a process by which multiple synaptic potentials combine within one postsynaptic neuron
Divergence and convergence of neurotransmitter effects occur in single neurons (T/F)
true
Drosophila melanogaster displayed temperature-dependent paralytic phenotype due to lack of sodium channels. Other way to get similar cellular mechanism:
Injection of TTX
Which side of the cerebellum affects the movements of the right hand?
Right
Axons of the nervous system are described as afferent and efferent according to the direction in which they carry information. Which is an efferent projection?
B. motor output of the spinal cord
The retina is part of the peripheral nervous system (T/F)
False
The central nervous system is derived from which tissue?
C. ectoderm
What is neurulation?
B. the process by which neural plate becomes neural tube
Which membrane lies closest to the brain?
A. pia mater
What are chemoreceptors?
chemically sensitive cells that serve as sensory receptors
The taste of amino acids is not confused with the taste of sweet or bitter chemicals because the taste cells express one class of receptor protein (T/F)
true
More than 90% of receptor cells respond to two or more basic tastes, reflecting a relatively unselective process (T/F)
true
What changes occur in taste receptors when the membrane is depolarized during receptor potential?
A. voltage gated calcium channels open, triggering NT release
What mechanism does the brain use to distinguish between smells?
D. all of the above
What is meant by threshold concentration for taste stimuli?
The concentration that evokes perception of taste
What is absorption?
B. the transfer of light energy to a particle or surface
Which cells in the retina have axons that leave the retina?
C. ganglion cells
What is the difference between ON-center ganglion cells and OFF-center ganglion cells?
ON-center ganglion cells receive inputs from ON bipolar cells while OFF-center ganglion cells receive inputs from OFF bipolar cells.
A center-surround receptive field consists of concentric circles with antagonistic responses to the presence of light (T/F)
true
Which layer contains the light sensitive elements of the retina?
D. photoreceptor layer
The range of wavelength in the visible electromagnetic spectrum is 100-1000 nm (T/F)
false
James, age 22, was riding a motorbike when he had an accident. A neuropsychological test revealed that James suffered extensive damage to area V4 in the ventral system. What is the most likely deficit resulting from a V4 lesion?
C. color perception
Susan fell down the staircase and injured her head, cause the transection of the left optic nerve. What is the consequence of this lesion?
C. blindness in the left eye
Which of the following is a major source of input to the LGN?
C. striate cortex
Mr Stewart underwent a surgery to remove a tumor in his brain. During the surgery, lesions developed in the optic radiations. What is the potential impact of these lesions?
C. blindness
Magnocellular LGN neurons project to layer IVCa, and parvocellular LGN neurons project to layer IVCb? (T/F)
true
Which of the following is most likely the basis of visual perception?
a. Hierarchical organization of visual receptive fields culminating in highly specialized cells such as grandmother cells
b. concerted activity of many neurons through the visual pathway
b. concerted activity of many neurons through the visual pathway
Which of the following is crucial for the tilt sensitivity of the macula?
D. otoliths
Which of the following is perceived as having a higher pitch?
D. high frequency sound waves
Which of the following is a function of vestibulo-ocular reflex (VOR)?
a. fixes sight on target during body movement by adjusting head, eye, and body positions
b. responds to changes in eye movement by adjusting the body position
a. fixes sight on target during body movement by adjusting head, eye, and body positions
A neural response triggered by a loud sound causes stapedius and tensor tympani muscles to contract. This response is called attenuation reflex (T/F)
true
Which of the following contributes to the pressure at the oval window being 20 times greater than that at the tympanic membrane?
B. ossicles act live levers
What role does the sensory motor cortex play in maintaining our perception of equilibrium and the execution of complex, coordinated movements?
A. maintaining a representation of body position and orientation in space
What are mechanoreceptors?
Sensitive to physical distortion
What is two point discrimination?
the smallest distance between two points that can be differentiated by the somatic sensory system
To which stimul do the majoirty of nociceptors respond?
D. all of the above
Information about pain and temperature is conducted more rapidly than information about touch perception (t/F)
false
Identify a type of hairless skin
glabrous
Which of the following primary afferent axons is the largest and fastest?
a. Aa
b. Ab
a. Aa
In the TED video Ramachandran discusses the case of a man who sees his mother and thinks she's an imposter, even though he recognizes her when she calls him on the phone. this is a case of:
B. prosopagnosia
A 2 year old boy has no reaction to any stimulation below the level of the umbicilous. he does not voluntarily move his limbs, his lower limb muscles are atrophied, and he has no voluntary control of his bladder or bowels. His mother reports that he had surgery on his back 2 days after birth, related to meningomyelocele. Above the level of the umbilicus, sensation and movement are within normal limits. The nervous system deficits affect which systems?
C. all
In the TED video, Pawan Sinha studied the arc of the recover period in children treated for visual disorders. Which of the following took the longest to recover, post surgery:
B. face detection
When you eat sour foods, protons are liberated and cause depolarization of a taste receptor (and ultimately release of a NT) through which mechanism?
a. proton binds to proton-gated sodium channels, causing influx of sodium and depolarization
b. proton binds to potassium channels, decreasing potassium permeability, which initiates depolarization
b. proton binds to potassium channels, decreasing potassium permeability, which initiates depolarization
The process by which the brain sums the responses of many, broadly-tuned sensory receptor cells to generate a unique fingerprint of environmental stimulus is called:
A. population coding
During neurulation, the ____ serve as precursers to vertebrae and skeletal muscle while the ____ give rise to peripheral nervous system neurons
A. somites, neural crest cells
Which of the following is not true about sweet and umami taste transduction?
contrasting "bitter", IP3 acts through only one mechanism to cause increased intracellular calcium
Which of the following is true about bitter taste transduction?
D. Both b (IP3...) and c (Phospholipase...)
Which brain imaging technique relies on detectiion of regional changes in blood flow or glucose input when a patient is exposed to stimuli?
A. fMRI
Which of the following statements is true about receptor cells
a. taste receptor cells always transmit information to the brain via basal cells and gustatory afferents
b. taste receptors possess unique thresholds to sweet, bitter, sour, salty, and umami
a. taste receptor cells always transmit information to the brain via basal cells and gustatory afferents
