Potassium (K+) is a positively charged ion in a neuron.
Understanding Potassium's Charge
Potassium, symbolized as K+, carries a single positive charge. This is because it has lost one electron. Within a neuron, potassium ions play a crucial role in maintaining the cell's resting membrane potential and in the generation of action potentials.
Key Characteristics of Potassium Ions within Neurons:
- Positive Charge: As stated in the reference, K+ is a positively charged ion.
- Intracellular Concentration: Potassium has a higher concentration inside the neuron (120 mM).
- Extracellular Concentration: Potassium's concentration outside the neuron is significantly lower (4 mM).
- Equilibrium Potential: The electrochemical equilibrium for potassium occurs at -90 mV. This means that potassium's movement across the cell membrane will balance out when the cell's interior is 90 mV more negative than its exterior, as per the reference information.
Role in Neuronal Function
The distribution of potassium ions, along with other ions like sodium (Na+), across the neuronal membrane is critical for the neuron's ability to communicate through electrical signals.
Summary of Potassium in Neurons:
| Feature | Description |
|---|---|
| Charge | Positively charged (K+) |
| Intracellular Conc. | 120 mM |
| Extracellular Conc. | 4 mM |
| Equilibrium Potential | -90 mV, indicating a tendency to move out of the cell when the cell interior is negative |
In conclusion, potassium ions are positively charged within a neuron, and their behavior is essential to the proper functioning of the nervous system.
