Biopsychology: The Brain and Behavior
The Neuron: Building Block of the Nervous System
How Neurons Communicate
A neuron is a nerve cell that transmits information throughout the body. Communication happens through an electrochemical process. An electrical impulse, called an action potential, travels down the axon. When it reaches the axon terminal, it triggers the release of chemical messengers called neurotransmitters into the synapse (the gap between neurons). These neurotransmitters then bind to the next neuron, continuing the signal.
Key Parts of a Neuron
Divisions of the Nervous System
The Nervous System
| Division | Sub-Division | Function |
|---|---|---|
| Central Nervous System (CNS) | Brain & Spinal Cord | The body's decision maker. |
| Peripheral Nervous System (PNS) | Somatic & Autonomic | Gathers information and transmits CNS decisions to other body parts. |
| PNS: Autonomic | Sympathetic & Parasympathetic | Controls self-regulated action of internal organs and glands (e.g., heart rate, digestion). |
Fight or Flight
The sympathetic nervous system arouses the body, mobilizing its energy in stressful situations (the 'fight-or-flight' response). The parasympathetic nervous system calms the body, conserving its energy ('rest and digest').
Which part of the neuron is responsible for receiving messages from other cells?
Dendrites are the tree-like extensions at the beginning of a neuron that help increase the surface area of the cell body and are covered with synapses.
Correct answer: Dendrite
What are the chemical messengers that cross the synaptic gaps between neurons?
Neurotransmitters are crucial for communication between neurons, affecting everything from mood to muscle movement.
Correct answer: Neurotransmitters