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• What does RMP stand for in cellular physiology?

  Resting membrane potential
• What is characteristic of all cells regarding RMP?

  Every cell has a resting membrane potential when it is not active.
• What determines the resting potential of a cell?

  The concentration gradients of ions across the membrane and membrane permeability to each type of ion.

  
• What is the approximate value of resting membrane potential (RMP)?

  • 70 mV
• How does the movement of Na+ and K+ ions contribute to RMP?

  Ions move down their gradients via channels, leading to a separation of charge that creates the resting potential.

  
• What is an action potential (A.P)?

  Action potential is a temporary shift in the neuron’s membrane potential caused by ions flowing in and out of the neuron.

  
• What happens to Na+ and K+ ions during the maintenance of RMP?

  3 Na+ ions exit the cell while 2 K+ ions enter the cell.

  
• Which types of cells can trigger an action potential?

  Nerve cells (neurons) and muscle cells (cardiac, smooth, and skeletal muscle).
• What types of stimuli can trigger an action potential?

  The stimulus can be electrical, physical, or chemical.
• What are mechanically gated channels?

  Channels that open in response to a physical stimulus.
• What are voltage-gated channels?

  Channels that open when the membrane potential reaches a certain level of polarization/depolarization.

  
• What is the function of the Na+ voltage-gated channel's activation gate (gate m)?

  It is normally closed and opens when the cell becomes more positive.

  
• What happens to the Na+ voltage-gated channel's deactivation gate (gate h) during depolarization?

  It swings shut and blocks sodium ions from entering the cell.

  
• What is the state of voltage-gated potassium channels during an action potential?

  They are either open or closed.

  
• What are the three main events that take place during an action potential?

  1. Triggering event causes depolarization.
  2. Depolarization occurs as sodium ions flow into the axon.
  3. Repolarization occurs as potassium ions exit the neuron.

  
• What occurs during the triggering event of an action potential?

  A signal from other cells causes positively charged ions to flow into the cell body.
• What is depolarization in the context of an action potential?

  It is the process where the membrane potential becomes less negative as positive ions flow into the cell.

  
• What happens during repolarization of an action potential?

  The inactivation gates of sodium channels close, stopping the influx of positive ions, while potassium channels open.

  
• What is hyperpolarization in the context of an action potential?

  It makes the cell more negative than its typical resting membrane potential.

  
• How does the sodium-potassium pump contribute to the resting state after an action potential?

  It works to reestablish the resting state after hyperpolarization.

  
• What is the definition of resting membrane potential (RMP)?

  The potential that exists in the cell when it is not doing anything.
• What role do anions play inside the cell during resting membrane potential?

  Anions are trapped inside the cell, contributing to the negative charge.

  
• How does action potential differ from resting membrane potential?

  Action potential involves a temporary shift from negative to positive membrane potential, while resting membrane potential is stable.
• What is the role of neurotransmitters in triggering action potentials?

  Neurotransmitters bind to channels and cause them to open, allowing ions to flow into the cell.
• Why is membrane potential significant in cellular activity?

  It determines the excitability of the cell and the ability to send signals.
• How do ion concentration gradients maintain resting membrane potential?

  They create a difference in charge across the membrane, contributing to the resting potential.

  
• What is the relationship between depolarization and action potential propagation?

  Depolarization allows for the opening of voltage-gated channels, propagating the action potential along the axon.

  
• What is the significance of the domino effect in the opening of voltage-gated channels?

  Once one channel opens, it triggers adjacent channels to open, propagating the action potential.
• How does the sodium-potassium pump maintain ion balance in the cell?

  It actively transports sodium out and potassium into the cell to maintain resting potential.