1. Nervous System Delanie Cyr Jacob Butcher Jacklyn Jaronik Claudia Bishop

2. Nervous system: Central and Peripheral  The Nervous system is stream lined to send rapid signals from cell to cell to maintain homeostasis and coordinate body organs and functions.

3. Central and Peripheral Systems  There are two basic types of nervous systems:  CNS (Central Nervous System)  PNS (Peripheral Nervous System)

4. Central Nervous System  Consists of the brain and spinal cord  It coordinates information received from sensory receptors and initiates responses

5. Peripheral Nervous System  Contains a afferent division composed of sensory receptors and sensory neurons, and an efferent division composed of motor neurons.

6. Sensory Receptors and Motor Nerves  Sensory receptors detect changes in the environment and transmits this information along sensory or afferent nerves to the CNS  Motor nerves transmits impulses from the CNS to the PNS

7. Structure of Nervous Tissue  Located in the brain, spinal cord, ganglia, and nerves.  It is composed of two types of cells, Neurons and Neuroglia  Neurons conduct action potentials and are the structural and functional units of nervous tissue  Neuroglia are cells that support, protect, and furnish nutrients to neurons, and augment the speed of neuron transmission

8. Structure of a Neuron  Can be over 3 feet long (longest nerve in your body)  Three basic parts to a neuron:  Dendrites - receive information from receptors or other neurons and send it back out to the cell body  Cell Body -usually has a triangular or cone shaped area called the axon hillock  Axon - extends from the axon hillock, is the elongated fiber that extends from the cell body to the terminal endings and transmits the neural signal.

10. Structure of a Neuroglia Cell  Generally smaller and more abundant the neurons.  Six types of neuroglia cells, four located in the CNS, and two located in the PNS.  CNS:  Astrocytes  Oligodendrocytes  Microglia  Ependymal Cells  PNS:  Schwann Cells  Satellite Cells

11. Classification of a Neuron  Three classifications of a neuron based on their function:  Sensory(afferent) - changes the stimulation into an action potential or nervous impulse that travels along the axon to a spinal cord.  Interneuron - structurally a multipolar neuron and comprises about 90% of the neurons in the CNS.  Motor neuron (efferent)- takes the impulse out of the spinal cord via a spinal nerve to an effector.