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.



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