Font size
WorksheetsNEUROBIO PROBELM SETS M1
Total questions: 28
Worksheet time: 15mins
The experiments that caused the mice to become artificially thirsty (experiment 1) or aggressive (experiment 2), both involved manipulations of neural activity in the hypothalamus. How did manipulating the same brain structure result in such different effects?
They activated neurons in experiment 1 and astrocytes in the experiment 2
They activated excitatory neurons in experiment 1 and inhibitory neurons in
experiment 2
They used strong stimulation in experiment 1 and weak stimulation in experiment 2
they activated nuerons in different hypothalamic nuclei in experiment 1 and 2
Why do we use secondary antibodies? Why don't we just attach labels directly to primary antibodies?
adding fluorescent labels would make the primary antibodies too large
secondary antibodies are more specific than primary antibodies
primary antibodies are generally not synthesized in lab, but made using animal immune systems
so the antibody companies sell more product
What are the three principle types of glia in the central nervous system?
astrocytes, schwann cells, microglia
astrocytes, oligodendrocytes, microglia
neurons, astrocytes, oligodendrocytes
elmer's, krazy glue, rubber cement
Which of the following is a function of the astrocytes?
uptake and recycling of neurotransmitters
making the myelin sheath
electrical signaling over long distances
identification and phagocytosis of pathogens
Why do we have unmyelinated axons? Why don't all axons have myelination if it make the action potentials faster?
myelinated axons take up more space in the nervous system
some signals do not need to be carried quickly
additional glia cells mean that myelin is more metabolically expensive
Why do PNS neurons generally have thicker myelin than CNS neurons?
signals in PNS are more crucial for survival
PNS axons usually have a longer distance to travel
PNS axons usually have a shorter distance to travel
PNS axons are bundled into fiber tracts
Why are gliomas worse than neuromas?
since glia are supporting cells, if glia die then neurons will die too
because glia are necessary for myelin
glia divide readily while neurons do not
there are more glia than neurons
Why does damage to the brainstem often have serious consequences?
Neurons in the brainstem control essential functions such as breathing, heart, rate, and wakefulness
The brainstem links the cortex to the thalamus
The brainstem links the cortex to the cerebellum
The brainstem links the cerebellum to the spinal cord
What task do you think a patient with a cerebellar lesion would struggle with?
Gross motor control (e.g., raising a hand in the air)
Fine motor control (e.g., picking up a thumbtack)
Initiating movement
Concluding a movement
Patient E.P. had bilateral damage to his hippocampus. What deficit did this cause?
Complete amnesia
Lack of normal fear responses
Inability to consolidate new memories
Problems regulating homeostatic functions
What is a key feature that differentiates the neocortex from other brain structures?
Neocortex is highly adaptable, and can process a wide range of different inputs
Neocortex has a unique layered structure not found in other brain regions
Neocortex has a highly ordered neural circuit
Neocortex is especially important for behavior and survival
What is the Nernst Equation used to calculate?
The resistance of the cell membrane
The concentration gradient of an ion across the cell membrane
The amount of current flowing across the cell membrane
The membrane voltage at which an ion will be in electrochemical equilibrium
How are the chemical gradients of Na+ and K+ maintained inside and outside of the cell?
Through Na + and K+ leak channels
The Na +/K+ ATPase
With ion-selective ion channels
With cation-nonspecific ion channels
The resting membrane potential is predominantly determined by relative concentrations of which ion?
K+
Na+
Ca2+
Mg+
Which of the following are responsible for determining the value of
the resting membrane potential?
VG Na+ channels
VG K+ channels
leak Na+ channels
leak K+ channels
One way to elicit action potentials in a neuron is to stimulate an input axon with high frequency stimulation. This is an example of which of the following?
spatial summation
temporal summation
coincidence detection
Another way to elicit action potentials in a neuron is to stimulate a bundle of input axons simultaneously. This is an example of which of the following?
spatial summation
temporal summation
coincidence detection
Which of the following represents the energy required to move a mole of an ion across a concentration gradient?
NRT
N z * F * E * ln([out]/[in])
NRT * ln([out]/[in])
R * T / (z * F) * ln([out]/[in])
Which of the following represents the energy required to move a mole of an ion across an electrical field?
NzFE
N z * F * E * ln([out]/[in])
R T / ( z * F)
R T / ( z * F) * ln([out]/[in])
You are hanging out in Hodgkin and Huxley’s lab recording from a squid giant axon. You have measured the concentration of K+ inside and outside the cell ([K+]in 400 mM, [K+]out 40 mM), please calculate the equilibrium potential for potassium (K+eq):
-58 mV
-65 mV
58 mV
65 mV
Hodgkin and Huxley have gone out for calamari cocktails, leaving you to determine the equilibrium potential of Ca2+. You have measured the concentration of Ca2+ inside and outside the cell ([Ca2+]in 50 mM, [Ca2+]out 500 mM), please calculate the equilibrium potential (Ca2+eq)
-65 mV
-58 mV
59 mV
29 mV
What causes the relative refractory period?
Inactivation of voltage-gated Na+ channels
Opening of voltage-gated Na+ channels
Inactivation of voltage-gated K+ channels
Opening of voltage-gated K+ channels
What does voltage clamp allow you measure that standard passive recording approaches (voltage recording or current clamp) do not?
The reversal potential of different types of ion channels
The conductance of different types of ion channels
Which currents are elicited at a specific voltage
None of the answers
During voltage clamp, if the membrane potential is held at +55 mV, then the Na+ conductance is high but the current is low. Why is that?
Because the K+ flux is counteracting the Na+ flux
Because the Na+ channels are open, but no ions are flowing through
Because at that voltage [Na+]out = [Na+]in
Because the concentration gradient is no longer favorable to Na+ entering the cell
What effect will increasing the membrane resistance have on axonal conduction?
It will decrease the amount of time it takes for the membrane to reach its final voltage
It will increase the capacitance of the membrane
It will cause the action potential to propagate farther before decaying
It will cause a signal to propagate a shorter distance before decaying
What effect will decreasing the capacitance have on axonal conduction?
It will cause the action potential to propagate farther before decaying
It will decrease the amount of time it takes for the membrane to reach its final voltage
It will cause the action potential to propagate a shorter distance before decaying
It will increase the amount of time it takes for the membrane to reach its final voltage
Channelrhodopsin is a light activated channel that is permeable to cations when open (assume PNa = PK; PCl = 0). Given the following concentrations, what would you expect the equilibrium potential of the channel to be?
-29 mV
+29 mV
0 mV
+58 mV
The GABA receptor is permeable to Cl-, but not other ions, what do you expect its equilibrium potential of the channel to be given the following ion concentrations?
-58 mV
-65 mV
-76 mV
-88 mV
