1. ANIMALS HAVE NERVOUS SYSTEMS THAT DETECT EXTERNAL AND INTERNAL SIGNALS, TRANSMIT AND INTEGRATE INFORMATION, AND PRODUCE RESPONSES WWW.LEARN.GENETICS.UTAH.EDU/CONTENT/BEGIN/CELLS/CEL LCOM/ Transmission of information results in changes within and between biological systems

2. The neuron is the basic structure of the nervous system that reflects function A typical neuron has a cell body, axon and dendrites. Many axons have a myelin sheath that acts as an electrical insulator. The structure allows for detection, generation, transmission and integration of signal information Dendrites Stimulus Nucleus Cell body Axon hillock Presynaptic cell Axon Synaptic terminals Synapse Postsynaptic cell Neurotransmitter

3. Neuron Structure & Function Schwann cells, which form the myelin sheath, are separated by gaps of unsheathed axon (nods of Ranvier) over which the impulse travels as the signal propagates along the neuron

4. Action potentials propagate impulses along neurons. Every cell has a voltage (difference in electrical charge) across its plasma membrane called a membrane potential The resting potential is the membrane potential of a neuron not sending signals The Na / K pump maintains concentrations gradients for Na+ and K+

5. In a resting neuron, the currents of K + and Na + are equal and opposite, and the resting potential across the membrane remains steady Membranes of neurons are polarized by the establishment of electrical potentials across the membranes

6. Fig. 48-10-5 Key Na + K+K+ +50 Action potential Threshold 0 1 4 5 1 –50 Resting potential Membrane potential (mV) –100 Time Extracellular fluid Plasma membrane Cytosol Inactivation loop Resting state Sodium channel Potassium channel Depolarization Rising phase of the action potential Falling phase of the action potential 5 Undershoot 2 3 2 1 3 4

7. Response to Stimulus Na+ and K+ gated channels sequentially open and cause the membrane to become locally depolarized Na+/K+ pumps, powered by ATP, work to maintain membrane potential

8. Fig. 48-15 Voltage-gated Ca 2+ channel Ca 2+ 1 2 3 4 Synaptic cleft Ligand-gated ion channels Postsynaptic membrane Presynaptic membrane Synaptic vesicles containing neurotransmitter 5 6 K+K+ Na + Transmission of information between neurons occurs across synapses www.ted.com/talks/sebastian_seung.html

9. NEUROTRANSMITTERS HTTP://YOUTU.BE/HANOQ8UBSYC In most animals, transmission across synapses involves chemical messengers called…

10. Neurotransmitters Transmission of information along neurons and synapses results in a response The response can be stimulatory or inhibitory The same neurotransmitter can produce different effects in different types of cells

11. MOUSE PARTY learn.genetics.utah.edu/content/addiction/drugs/mouse.html LEARN HOW DRUGS DISRUPT THE SYNAPSE TO MAKE THE USER FEEL “HIGH”

12. Vertebrate Brain Different regions of the brain have different functions Group Assignment – select a topic, research it, summarize it (in writing with an illustration) and share what you learned with the class.  Explain effect of the neurotransmitters - Acetylcholine, Epinephrine and norepinephrine, Dopamine, Serotonin, and GABA  Identify regions of the brain responsible for vision, hearing, muscle movement, abstract thought, emotion, neuro-hormone production  Identify structures and functions of Forebrain, Midbrain, Hindbrain, and Left & Right cerebral hemispheres  Explain how interaction and coordination between the muscular and nervous systems allow for essential biological activities  Describe how the nervous system detects signals (internal & external), transmits & integrates information and produce responses.  How does the vertebrate brain integrates information to produce a response.