1. Objectives To identify the roles of the three types of neurons and the transmission pathway of a reflex arc. To analyze case studies (patient symptoms) to hypothesize possible regions of the brain damaged or affected.

2. Questions to Ponder…. Record the following questions in your notebooks. You will answer these at the end of the block. 1.Where are interneurons found? 2. Anesthesia blocks which type of neuron from communicating with the brain?

3. Think about how form follows function of a neuron below…can you determine what each component does based on what you already know about nervous tissue?

4. Types of Neurons Motor: impulses from CNS to muscles or glands (mostly multipolar). Sensory: impulses from sensory receptors to the CNS (many are unipolar). Interneurons: impulses conducted within the CNS (often multipolar).

5. Nervous Tissue All nervous tissue is composed of only two types of cells: Nerve cells (neurons) and supporting cells (neuroglia). Neurons vary in appearance, but all have 1) cell body, 2) dendrite, and 3) axon. Neurolemmocyte (Schwann cell): specialized neuroglial cell of the PNS that creates myelin.

6. Motor Neuron

7. Sensory Neuron

8. Interneuron

9. CNS: Spinal Cord Function Communication between the Brain and the PNS. Example: hand touched  sensory fibers generate nerve impulses  passes through sensory neurons  spinal cord  ascending tract  brain. Center for reflex arcs. A stimulus causes sensory receptors to generate nerve impulses through sensory nerves these go to interneurons that integrate the data and respond.