Biology Essentials - Ion Channels, Cell membrane, Sodium potassium pump and Action Potential

Specialized proteins that provide a passageway for charged ions through the plasma membrane down their electrochemical gradient.

Insulin binds with receptors to creates channels for glucose to enter cells

a phospholipid bilayer

Two layers of phospholipids with hydrophilic heads and hydrophobic tails that form a membrane

Uses energy to move sodium and potassium through the membrane against the concentration gradient to maintain electrical gradient

The difference in charges between the inside and outside of the cell due to ions

A hypotonic solution is a solution that has a lower concentration of solute compared to the cell

A solution that contains more dissolved particles than is found in normal cells

A substance that produces ions when dissolved in water

The concentration of solutes outside the cell is equal to the concentration inside the cell

Sodium, chloride, potassium and calcium

A rapid rise and subsequent fall in membrane potential across a cellular membrane

The cell will contract

The imbalance of electrical charge between the inside and outside of the neurons. More negative on the inside

Sodium is higher outside and potassium is higher inside

The membrane potential becomes less negative (more positive)

The membrane potential becomes more negative

A stimulus causes sodium channels to open and because there are more sodium ions on the outside, sodium ions move into the neuron. Sodium has a positive charge, so the neuron becomes positive and depolarized. potassium channels open, potassium leaves the cell, reversing the depolarization. Gradually, they go back to resting levels

To allow for cell to cell communication and the sharing of signals along the neurons axon

Ratio of 3 sodium ions out for every 2 potassium ions brought in.

Medication can be used to cause certain cells of the body to contract through the movement of sodium