The Nervous System
Nervous System Divided into: Central Nervous System (CNS) Controls the _________ Peripheral Nervous System (PNS) Relays ___________ b/w brain and body body CNS (brain and spinal cord) PNS (Nerves of the body) communication
Basic Functions of the Nervous System Sensory ____________ Integration Motor Responds to signals Maintains ______________ Gathers info Processes info Sensory (input from the five senses), Integration by brain or spinal cord, Motor = response homeostasis
The Neuron
Myelination Schwann Cells (PNS) Produce/maintains the ______________ for each axon Myelin sheath _________ the speed of ______________ Increase with age myelin sheath Increases nerve impulses
CNS vs PNS http://www.youtube.com/watch?v=cGSXaWJD75U http://www.youtube.com/watch?v=_vx1OVLX5Rc Source of thoughts, emotions and memories
Table Talk Which division of the nervous system was activated by the video clip? Why are babies less coordinated than adults? Their neurons are not fully myelinated Signals are not sent as fast as in adults This continues into teenage years
Structural Classification of Neurons Determined by the # processes attached to the cell body Process
How do cells communicate? Use neurotransmitters Neurotransmitters are released into ____________ the synapse A synapse is the gap between an axon terminal and a dendrite. Neurotransmitters are chemical messengers. Once released neurotransmitters are released into the synapse, they bind to a specific receptor, this elicits a response.
How does temperature effect neurons? ________________ the release of neurotransmitters ________________ are not firing as quickly Cold slows down https://www.youtube.com/watch?v=fgqfQuivDrU https://www.youtube.com/watch?v=dTKPWpx89No Action potentials
Action Potentials http://www.youtube.com/watch?v=ifD1YG07fB8
Action Potentials Resting Potential Action Potential
Action Potentials and Neurotransmitters When the action potential reaches the axon terminal
Excitatory vs Inhibitory action potentials release of neurotransmitter Inhibitory
Dopamine Causes feelings of euphoria Activates the pleasure center Both excitatory (elevates mood) and inhibitory (depression)
Nervous System Lab Analysis Was there a difference in the average distances between arms and fingers for the meter stick drop? Why do you think this is the case? How many hours of sleep did you get the night before our lab? Do you think there is correlation between reaction time and amount of sleep? Explain your reasoning. Was there a difference in average distance between neurons in the different areas tested on your body? Which was the shortest and which was the longest? Why do you think this is the case?
Blind Spot Photoreceptors Optic Nerve Specialized neurons in the eye No photoreceptors No info to brain Brain “makes up” missing info