Pt2 flash card

Membrane Potential

The difference in electrical charge across a plasma membrane due to unequal distribution of ions.

Resting Potential

The membrane potential of a cell when it's not receiving an active signal, typically at -90 millivolts for skeletal muscle cells.

Action Potential

A rapid change in membrane potential from resting potential to a positive value, triggering muscle contraction.

Sodium-Potassium Pump

A carrier protein that moves sodium ions out of the cell and potassium ions into the cell to maintain resting potential.

Electrical Gradient

A difference in electrical charges across the membrane; negative inside and positive outside.

Depolarization

The process during action potential where the membrane potential becomes less negative and approaches 0.

Repolarization

The process following depolarization that returns the membrane potential back to resting potential.

Gated Ion Channels

Channels that open or close in response to specific signals, such as voltage changes or ligand binding.

Ligand-Gated Channels

Ion channels that open in response to the binding of a specific chemical (ligand).

Voltage-Gated Channels

Ion channels that open or close in response to changes in membrane voltage.

Concentration Gradient

A situation where ions move from areas of higher concentration to areas of lower concentration.

Kinetic Energy

The energy associated with movement, converted from potential energy when ions diffuse.

Channel Protein

Proteins that form channels in the cell membrane, allowing specific ions to pass through.

Millivolt

A unit of measurement for electricity, representing one-thousandth of a volt.