Neuronal Signaling: Graded Potential Flashcards
Organization of the nervous system: What is the CNS Central Nervous System?
Brain and Spinal Cord.
Organization of the nervous system: What is the PNS Perioheral Nervous System? (3)
Afferent Divison: sensory neurons that send information into the CNS.
Efferent Division: neurons that convey information from the CNS out to control muscle and glands.
Enteric Nervous System: neurons involved in digestive function.
What is the purpose of neurons and what does neuron signaling involve?
Purpose: neurons are the main information processing cells of the nervous system.
Involve: changes in membrane potential
Fill in the blanks:
What is integration in a neuron?
Adding all of the different signals that the neuron is getting together and deciding what to do with that information. (Release signal or not, how excited the cell would be, etc).
Define what Glia are.
Important support cells for neurons.
What are the 3 types of Glial cells you need to know for this class?
What are Schwann Cells? Where are the located? What do they do?
Glial cells.
PNS.
Myelin forming cells.
What are oligodendrocytes? Where are they located? What do they do?
Glial cells.
CNS.
Myelin forming cells.
What are astrocytes? Where are they located? What do they do?
Glial cells.
CNS.
Abundant support cells in the CNS help maintain interstitial fluid around neurons .
There are two basic types of electrical signals and neurons. What are they?
Graded potential: input signals that occur in dendrites and cell body. input and integration
Action potentials: the axon conducts action potentials. output
How do graded potentials arise in sensory neurons?(Afferent neurons)
Convert energy signal from the environment into a change in membrane potential.(circled)
This picture shows a regular neuron. How do Afferent neurons differ?
Cell body on the stock half way along the neuron and clustered in ganglion.
What are the gated channels that Afferent neurons use?
Temperature gated channels
Mechanically gated channels
These can be called receptor potentials in Afferent neurons .
Explain “identification of temperature gated ion channels”, with specific temperature gated channels.
How they did it:
Revist lecture/ask prof.
BOTH temp and ligand gated!
Notes:
TRPV1: one of the temperature gated channels that are opened by capsaicin. (Not first to be discovered or anything)
Capsaicin activates the noxious heat channel.
Menthol activates the cool sensing channel
Explain “identification of mechanically gated ion channels”.
What is the structure of mechanically added ion channels?
Where do you find mechanically gated ion channels in Afferent neurons?
Sensory Dendrites.
What is the Meissner’s corpuscle?
The Meissner’s corpuscle is a skin sensor that
responds to fine touch
How do Meissner’s corpuscle’s (and other touch sensory neurons) work functionally?
Brief touch=breif signal
Long touch= long signal
Explain how postsynaptic potentials are graded potentials using this figure.
Explain what the postsynaptic potential is due to in these figures?
What channels can open in the postsynaptic neuron to make it excitatory?
Options: Na+, K+, Ca++, or Cl-?
Na+ or Ca++
What channels can open in the postsynaptic neuron to make it inhibitory?
Options: Na+, K+, Ca++, or Cl-?
K+ or Cl-
How far do gated potentials usually travel? Why does it travel this distance?
Not far at all.
This is because the current dissipates as it move through the cell, due to: 1. Leak channels 2. Cytoplasmic resistance.
Graded potentials do not travel long distances. This is a problem since we have very long neurons that need to reach out fingers and toes to our CNS. How are we able to still have Afferent neurons so far away?
The initial signal only has to travel to the trigger zone after that action potentials carry out the rest of the signal, as action potential can travel far without decrement.
Note: action potentials are a type of signal that are all or nothing!
