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

What Each Brain Part Does Open Website

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.cbsnews.com/stories/2002/01/08/60II/main323596.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?