Upload
frank-holt
View
223
Download
0
Tags:
Embed Size (px)
Citation preview
Nervous SystemNervous System
FunctionFunction
Allows your body to react to your Allows your body to react to your environment and stimuli.environment and stimuli.
OrgansOrgans
BrainBrain
Spinal cordSpinal cord
Nerve cells (neurons)Nerve cells (neurons)
BrainBrain
Coordinates all of your body’s activitiesCoordinates all of your body’s activities
3 parts: cerebrum, cerebellum, brain stem3 parts: cerebrum, cerebellum, brain stem
Cerebrum
Cerebellum
Brain Stem
https://www.youtube.com/watch?v=rSQNi5sAwuc
Spinal cordSpinal cord
43 cm long and the diameter of your thumb43 cm long and the diameter of your thumb
Made of bundles of neurons to carry signals Made of bundles of neurons to carry signals to and from the brain from the rest of the to and from the brain from the rest of the body.body.
NeuronsNeuronsParts: Parts: – Cell body Cell body – Dendrites (receive input)Dendrites (receive input)– Axons (deliver message)Axons (deliver message)
Direction of message
How it worksHow it works
Nerve Nerve MessagesMessages
Messages sent through a Messages sent through a synapsesynapse (gap) (gap)
https://www.youtube.com/watch?v=p5zFgT4aofA
https://www.youtube.com/watch?v=WhowH0kb7n0
Messages move along neurons like batons Messages move along neurons like batons in a relay race to spine, brain, and backin a relay race to spine, brain, and back
120 meters/second120 meters/second
These signals can continue to These signals can continue to work even if the brain is not work even if the brain is not
sending the signalsending the signalhttps://www.youtube.com/watch?https://www.youtube.com/watch?v=2YZJt_Bw3eo (twitching frog legs)v=2YZJt_Bw3eo (twitching frog legs)
https://www.youtube.com/watch?https://www.youtube.com/watch?v=rSQNi5sAwuc (TED talk- control v=rSQNi5sAwuc (TED talk- control someone else’s arm with your brain)someone else’s arm with your brain)
ReflexReflex
Involuntary, automatic response to a Involuntary, automatic response to a stimulus (hot, cold, sharp)stimulus (hot, cold, sharp)
They can’t be controlled because they They can’t be controlled because they occur before you know what happened.occur before you know what happened.
Reflex responses are controlled by spinal Reflex responses are controlled by spinal cord, not brain = faster responsecord, not brain = faster response
Examples of reflexesExamples of reflexes
Blinking, sneezing, knee tap, flinching, etc.Blinking, sneezing, knee tap, flinching, etc.
diving, grasping, and moro (in babies)diving, grasping, and moro (in babies)
Diving
Drug EffectsDrug EffectsDepressants (alcohol and Depressants (alcohol and marijuana) – slow your nervous marijuana) – slow your nervous system response timesystem response time
Stimulants (caffeine and Stimulants (caffeine and methamphetamines) – speed up methamphetamines) – speed up activityactivity
https://www.youtube.com/watch?v=4spIzhl2cGE
reviewreview
https://www.youtube.com/watch?https://www.youtube.com/watch?v=jJfESattZOYv=jJfESattZOY