1. The Neural System:

• Complex network of specialized cells.

• Controls and coordinates bodily functions.

• Receives, processes, and responds to stimuli.

• Maintains internal balance.

2. The Neuron - Structural and Functional Unit:

• Neuron is the basic unit of the nervous system.

• Consists of cell body (soma), dendrites, and axon.

• Neurons transmit nerve impulses.

3. Axon:

• Long projection from neuron’s cell body.

• Conducts nerve impulses away from the cell body.

• Covered by myelin sheath for insulation.

4. Generation and Conduction of Nerve Impulse:

• Nerve impulse is an electrochemical signal.

• Action potential is the basis of nerve impulse.

• Travels down the axon for information transmission.

5. Three Kinds of Neurons:

• Sensory Neurons: Transmit sensory info to CNS.

• Interneurons: Found in CNS, process information

• Motor Neurons: Transmit signals to effectors (muscles, glands).

6. Key Fact About Ion Channels:

• Ion channels control ion flow across neuron membranes.

• Vital for resting membrane potential and action potentials.

7. Transmission of Impulses:

• Impulses transferred between neurons at synapses.

• Neurotransmitters relay messages.

8. Synaptic Transmission Across a Chemical Synapse:

• Action potential reaches axon terminal.

• Calcium channels open, triggering neurotransmitter release.

• Neurotransmitters bind to postsynaptic receptors.

• Change in membrane potential generates new action potential.