List, in order, the events in visual perception that must occur for a person to see an object:
1. Potassium channels opens, allowing potassium ions to move out.
2. Some sodium channels open in the dendrite.
3. All ion channels close and the Na+/K+ exchange pump starts working.
4. Sodium ions diffuse toward a node of Ranvier.
5. Lights hit the retina.
6. The threshold level is reached.
7. Many sodium channels open in the axon membrane, allowing sodium ions to move in.