Transcript Chapter 11
Chapter 35 The Nervous System Question of the day • What degenerative nerve disease is named after a famous baseball player? • Lou Gehrig’s Disease • A.K.A. - ALS • Attacks nerve cells and kills them • Over time a person is unable to move • Ch. 35 Essential Questions • How does a Neuron work? • What is homeostasis? • What are the main parts of the brain? • How does each function? • What are the 5 senses? • How do drugs affect the nervous system? 35-1 Homeostasis • Humans maintain a specific condition • They keep a static internal environment • One that doesn’t change • HOMEOSTASIS • What is the same? • Body Temp 35-2 Nervous System • Start little • Smallest piece is a NEURON • Parts of a Neuron: • Cell Body (w/Nucleus) • Axon - string to other neurons • Dendrites - fingers/ branches • Myelin Sheath - cover for axon • Terminals - branches to other neurons How a Neuron transmits a signal • • • • • • Need a stimulus - starts: Sodium - Potassium Pump Just like ETC Na+ gets pushed out, Creates a negative potential Signal follows neg. potential down axon • To synapse where it transfers to another neuron Neurotransmitters • Things that move a nerve impulse from 1 neuron to another 35-3 Big Nervous System • Central Nervous System • Starts with your Brain • Includes Spinal Cord • Peripheral nerves (in appendages) Parts of Your Brain • Cerebrum - contains all the lobes (main part) • Cerebellum - back part • Brain Stem - spinal cord • Meninges - fluid that protects brain 35-4 The Senses • • • • • • 5 Main Senses Vision Hearing & Balance Smell Taste Touch Question of the day • What kind of animals see at night? • Nocturnal • What part of their eye is most developed? • Rods - sensitive to light and motion • Cones - color sensitive Vision • Helps sense light & Color • Rods • Cones • Parts of Eye • Cornea • Pupil • Lens • Retina • Optic Nerve Hearing • Also has to do with balance • Sound waves hit Tympanum • Vibrations cause cochlear nerve to move • Sends info to Temporal Lobe for interpretation • Need to pop ears • Clearing out Eustachian tubes Smell & Taste • The two are connected • Smell - also called Olfactory • Helps sense 1000s of smells & tastes • Connected to your parietal lobe • Sinuses - Nose • Tongue - Mouth • Salivary Glands Touch • Has to do with the integumentary system • Or your skin • Hair & nerves on skin sense pressure • Can feel: • Temperature • Pain • Wind or other stimulus Is there a 6th sense? • Synthesia • A condition where 2 senses fuse together • Gives the person rare ability to feel a different sense • http://www.cbsnew s.com/stories/200 2/01/08/60II/main3 23596.shtml What Drugs Do to Your Brain • STIMULANTS • Increase Blood Pressure, heart & breathing rate • Release neurotransmitters in brain • When over, user comes down off high • Cocaine, Caffeine, Amphetamines • DEPRESSANTS • Opposite of stimulants • Slows down heart, lungs, etc. • Tranquilizers, alcohol • OPIATES • Pain Relievers, like depressants • Morphine, Codeine Feeling Nervous? What makes you nervous? How do you deal with nerves?