Key Concepts on Neural Function and Nervous System Review
Neuron Resting Potential
- Resting Potential Mechanism:
- Neuron maintains resting potential by using Na+/K+ active transport pumps.
- These pumps move 3 Na+ ions out of the cell using ATP.
- Sodium (Na+) ions leak slowly into the cell, while Potassium (K+) ions leak rapidly out of the cell.
- The process maintains a positively charged membrane on the outside and a negatively charged membrane on the inside.
Neuron Depolarization
- Process of Depolarization:
- Depolarization occurs when there are more positively charged ions inside the cell than outside.
- A threshold stimulus (greater than -55 mV) triggers the opening of Na+ voltage-regulated channels.
- Na+ ions diffuse inward, causing the membrane to depolarize.
- The outside of the membrane becomes more negatively charged compared to the inside.
Neuron Repolarization
- Process of Repolarization:
- Repolarization restores the positive charge on the outside and negative charge inside the cell.
- Sodium voltage-regulated channels close, preventing Na+ influx.
- K+ ions diffuse outward through open K+ channels, repolarizing the membrane.
- The movement of K+ to the outside creates a more positive exterior of the cell again.
Nervous System Review
- Key Vocabulary for Exam:
- Dendrites, Motor neuron, Effector, Sensory neuron, Pineal gland, Synapse, Neuroglia, Hypothalamus, Reflex, Schwann cells, SNS, PNS, Sensory memory, Short-term memory, Working memory, Long-term memory.
- Sympathetic vs. Parasympathetic Pathways:
- Understand their roles in homeostasis.
- Action Potentials:
- Describe how nerve impulses travel along a neuron.
- Memory Types:
- Identify the four types of memory.
- Reflex Differences:
- Compare 2-neuron reflexes and 3-neuron reflexes.
- Brain Anatomy Diagram:
- Label nucleus, dendrites, cell body, axon, neuromuscular junction, neurilemma, Schwann cell, nodes of Ranvier, myelin.
- Functions of Brain Regions:
- Frontal lobe, Temporal lobe, Parietal lobe, Cerebellum, Occipital lobe, Brain stem.