2. Electrical Signals Are the Vocabulary of the Nervous System Flashcards
What is the resting potential of a neuron?
The difference in electrical charge between the interior and exterior of a neuron, typically ranging from –50 to –80 mV.
What property of neurons refers to their interior being more negative than the exterior?
Polarity.
What are ion channels?
Proteins in the neuronal membrane that allow specific ions, such as potassium (K+), to move across while blocking others like sodium (Na+).
What is the role of selective permeability in neurons?
It maintains the resting potential by allowing certain ions to pass through the membrane while restricting others.
How do potassium ions (K+) move according to their concentration gradient?
They diffuse from areas of high concentration inside the cell to areas of lower concentration outside.
What is electrostatic pressure?
The force that pulls positive potassium ions (K+) back inside the negatively charged neuron, counteracting the diffusion force.
What is the sodium-potassium pump, and what does it do?
A protein that actively moves three sodium ions (Na+) out of the cell and two potassium ions (K+) into the cell, using energy to maintain ion gradients.
Why is the sodium-potassium pump important?
It helps maintain the neuron’s resting potential by ensuring a proper balance of sodium and potassium ions.
What is the equilibrium potential in a neuron?
The point at which the outward diffusion of K+ ions is balanced by the inward electrostatic pull, resulting in a stable electrical charge.
How does the balance of forces contribute to neural function?
It allows neurons to maintain their resting state, preparing them to respond to stimuli.
