Neuro Lab 1- Resistor- Capacitor Circuits

Question 1

what is RC

Answer 1

• RC: resistance and capacitance

Question 1

how can the brain be descbied

Answer 1

• Brain can be described in terms of circuits (RC circuits)

Question 2

when a current flows through a resistor, what happens

Answer 2

• Resistor converts electrical energy into heat when current flows through it. This creates a voltage drop across the resistor

Question 3

how is resistacne applied to a neuron

Answer 3

• NEURON: resistance is determined by the opening and closing of ion channels . More ion channels open= more ions able to flow. Can be represented with resistsors since they resists the flow of electricity

Question 4

what is conductance

Answer 4

• Conductance is the inverse of resistance (1/r)

Question 5

series

Answer 5

• Series: all components are connected end to end to form a single path

Question 6

parallel

Answer 6

• Parallel: all components connected across eachother with exactly two electrically common nodes with the same boltage across each component

Question 7

what is a capacitor

Answer 7

• Capacitors are defined by two conducting substamces separated by a non-conducting substance in the middle. They accumulate electric charge on the insulatr which creates an electric fiel between the conductors and stores electrical energy

Question 8

how does the neuron have a conductor

Answer 8

• Intra and extracellular spaces are conductive, lipid bilayer is not

Question 9

what is tau

Answer 9

• Tau I the exponential increase in the voltage measurement up to the steady state which is the RC time constant (Tau)
• Tau Is the time the voltage takes to reach about 2/3 of its steady state level

Question 10

circuit with capacitor vs without

Answer 10

• Without a capacitor, the maximum voltage is the same as with, but it is reached way quicker

Question 11

capacitance in a neuron

Answer 11

• Capacitance is proportional to surface area. A larger neuron would have higher capacipance and thus an increased ability to store charge. Myelination acts as an insulating sheet which reduces capacictance of the membrane by increasing the thickness. Thicker= increases distance between extra and intracellular= decreased capacitance