Unmyelinated and Myelinated Axons
Ions – Cations and Anions
- Many types of ions are dissolved in the water environment that surrounds the neuron cell membrane.
- Ions are charged particles that form when atoms and molecules gain or lose one or more electrons.
- Atoms or molecules that lose electrons become positively charged and are called cations.
- In contrast, those that gain electrons become negatively chargedand are called anions.
- In a water environment there are many ions. Sodium (Na+) , Potassium (K+), Calcium (Ca+2), Chloride (Cl-), and proteins (-) are the most common.
- Ions attract nearby polar water molecules.
- The resulting hydration layers keep anions and cations separated, which allows the ions to remain dissolved in the water.
- If the hydration layers are removed, molecules such as NaCl (sodium chloride) or KCl (potassium chloride) will form due to ionic bonding between the anions and cations.