Membrane Potential: RMP, Graded potentials & APs

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What is the term used to describe the charge difference across the membrane of cells?

Cellular charge

Membrane potential (correct)

Cellular voltage

Membrane charge

What instrument is used to measure the membrane potential of cells?

Voltmeter (correct)

Speedometer

Thermometer

Barometer

In which units is the membrane potential typically measured?

Volts

Joules

Millivolts (correct)

Watts

What type of cells are capable of changing their membrane potential to produce action potentials?

Excitable cells Signup and view all the answers

What is the average resting membrane potential for most neurons?

-70 mV Signup and view all the answers

Which pump plays a role in creating the charge difference at resting membrane potential by pumping out 3 Na+ for every 2 K+ it brings in?

Na+/K+ pump Signup and view all the answers

Which of the following cells are NOT capable of producing graded potentials or action potentials when stimulated?

Blood cells Signup and view all the answers

What ions contribute to the differences in concentrations inside and outside the cell, leading to the resting membrane potential?

Na+, K+, Cl- Signup and view all the answers

What is the typical resting membrane potential for excitable cells like muscle cells and sensory receptors?

-70 mV Signup and view all the answers

Why are excitables cells capable of changing their membrane potential?

To produce graded potentials and action potentials when stimulated Signup and view all the answers

What is the net effect each time the Na+/K+ pump carries out its function?

Loss of 1 positive charge Signup and view all the answers

What contributes to the negative charge inside the cell at resting membrane potential?

Presence of fixed anions Signup and view all the answers

What is the primary reason for the relatively more negative charge inside the cell compared to outside?

Movement of K+ out of the cell Signup and view all the answers

What term is used to describe changes in the charge difference across the membrane of variable strength?

Graded potentials Signup and view all the answers

'Depolarization' events make it more likely for a response to happen in a cell because they make the cell more ___.

Positive inside Signup and view all the answers

'Hyperpolarization' events are referred to as inhibitory because they make it less likely for a response to happen by making the cell more ___.

Negative inside Signup and view all the answers

What is the typical threshold level of depolarization for most neurons to 'fire'?

-55 mV Signup and view all the answers

'Action potentials' rely on the opening and closing of which channels in neurons?

Voltage-gated sodium ion and voltage-gated potassium ion channels Signup and view all the answers

'Repolarization' refers to the process where the cell returns back to resting membrane potential after ___ occurs.

'Depolarization' Signup and view all the answers

'Graded potentials' occur in which parts of a neuron?

'Dendrites and cell body' Signup and view all the answers

Match the following terms with their descriptions:

Depolarization = The cell becomes more positive inside Hyperpolarization = The cell becomes more negative than resting membrane potential Repolarization = The cell returns to resting membrane potential after depolarizing Action potentials = Brief, all-or-none electrical events where the cell temporarily becomes positive & then returns back to negative Signup and view all the answers

Match the following types of membrane potential with their descriptions:

Resting membrane potential = Charge difference across the membrane when neuron is unstimulated Graded potentials = Variable strength changes in membrane potential Action potentials = Rely on opening and closing of specific channels in neurons Depolarization = Event that makes it more likely for a cell to respond Signup and view all the answers

Match the following ions with their role in contributing to resting membrane potential:

Na+ = Higher concentration outside the cell K+ = Higher concentration inside the cell Cl- = Concentration differences contribute to charge imbalance Ca2+ = Minor contribution to resting membrane potential Signup and view all the answers

Match the following ion movements with their effects on membrane potential:

Na+ moving into the cell = Makes the cell more positive inside K+ moving out of the cell = Makes the cell more negative inside Na+ moving out of the cell = Not mentioned in the text K+ moving into the cell = Not mentioned in the text Signup and view all the answers

Match the following terms with their impact on cellular response:

Depolarization events = Make it more likely for a response to happen in the cell Hyperpolarization events = Make it less likely for a response to happen in the cell Repolarization events = Not mentioned in the text Graded potentials = Not mentioned in the text Signup and view all the answers

Match the following terms with their descriptions:

Hyperpolarization = Events that make it less likely for a cell to respond Repolarization = Process of returning back to resting membrane potential after an event Excitable cells = Capable of changing membrane potential to produce action potentials Threshold level = Minimum depolarization needed for a neuron to 'fire' Signup and view all the answers

Match the following events with their impact on membrane potential:

Na+/K+ pump function = Contributes to charge difference by pumping ions in and out of the cell Depolarization = Makes the cell more likely to respond by decreasing charge difference Hyperpolarization = Decreases likelihood of response by increasing charge difference Repolarization = Process of restoring charge balance after an event Signup and view all the answers

Match the following descriptions with their corresponding terms:

Excitatory events = Make it more likely for a response to happen in the cell Inhibitory events = Make it less likely for a response to happen in the cell Graded potentials = Changes in charge difference across membrane of variable strength Action potentials = Only occur in the axon of a neuron and rely on specific ion channels Signup and view all the answers

Match the following terms with their roles in cellular function:

Threshold level of depolarization = Determines if a neuron will 'fire' or not Net effect of Na+/K+ pump function = Results in a loss of 1 positive charge each time it pumps Fixed anions inside the cell = Contribute to the relatively negative charge inside at resting membrane potential Presence of K+ leakage channels = Allows K+ to move out, making the inside of the cell more negative Signup and view all the answers

Match the following terms with their measurement units:

Membrane potential = Measured in millivolts (mV) Graded potentials = Changes in strength measured in mV Voltmeter = Instrument used to measure membrane potential Action potentials = Relies on specific voltage levels for firing Signup and view all the answers

What is the significance of the overshoot during hyperpolarization in an action potential?

It makes the cell more negative than the resting membrane potential. Signup and view all the answers

What role do chemically-regulated channels play in influencing membrane permeability?

They are controlled by neurotransmitters binding to receptors. Signup and view all the answers

What is the primary function of leakage channels in a cell?

Maintaining the resting membrane potential. Signup and view all the answers

Which ion channels open first during an action potential, leading to depolarization?

Sodium channels Signup and view all the answers

What is the role of voltage-gated ion channels like potassium during an action potential?

Play a crucial role in repolarization and hyperpolarization. Signup and view all the answers

How does an excitatory stimulus affect the membrane potential of a cell?

Triggers positive charges to enter the cell. Signup and view all the answers