central nervous system (cns)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… ·...
TRANSCRIPT
![Page 1: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/1.jpg)
![Page 2: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/2.jpg)
![Page 3: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/3.jpg)
Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS) = nerves
throughout body
Sensory receptors: collect info
Sensory neurons: body brain/SC
Motor neurons: brain/SC body (muscles, glands)
Interneurons: connect sensory & motor neurons Nerves = bundles of neurons
Contains motor neurons +/or sensory neurons
![Page 4: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/4.jpg)
![Page 5: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/5.jpg)
![Page 6: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/6.jpg)
Peripheral nervous system
Somatic nervous system
Autonomic nervous system
Sympathetic division
Parasympathetic division
Enteric division
![Page 7: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/7.jpg)
![Page 8: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/8.jpg)
cell body: nucleus, organelles dendrites: receive incoming messages axons: transmit messages to other cells myelin sheath: insulates axon, speeds up nerve impulses synapse: junction between 2 neurons neurotransmitter: chemical messengers sent across
synapse
Eg. acetylcholine, dopamine, serotonin glia (glial): support cells
Astrocytes, oligodendrocytes (forms CNS myelin sheath), Schwann cells (forms PNS myelin sheath)
![Page 9: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/9.jpg)
![Page 10: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/10.jpg)
Microelectrode
Reference electrode
Voltage recorder
–70 mV
![Page 11: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/11.jpg)
A Na+/K+ pump maintains a negative potential inside the neuron.
![Page 12: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/12.jpg)
Resting potential: membrane potential at rest
Voltage-gated Na+ channel = closed High Na+ outside / High K+ inside cell Nerve impulse: change in membrane potential =
action potential
Action potential – neuron membrane depolarizes and causes all-or-nothing response
Voltage-gated
Na+ channels
open
Na+ enters cell K+ channels
open K+ leaves cell
![Page 13: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/13.jpg)
![Page 14: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/14.jpg)
Conduction of an action
potential
![Page 15: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/15.jpg)
Saltatory conduction speed: 120 m/sec
![Page 16: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/16.jpg)
![Page 17: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/17.jpg)
Released by presynaptic membrane into the synaptic cleft
Bind to receptors on postsynaptic membrane, then broken down by enzymes or taken back up into surrounding cells
Types of neurotransmitters:
Excitatory: speed up impulses by causing depolarization of postsynaptic membrane
Inhibitory: slow impulses by causing hyperpolarization of postsynaptic membrane
![Page 18: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/18.jpg)
Acetylcholine: very common neurotransmitter, can be excitatory or inhibitory
Other common neurotransmitters: epinephrine, norepinephrine, dopamine, serotonin
![Page 19: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/19.jpg)
![Page 20: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/20.jpg)
Nicotine: mimics acetylcholine – speeds heart rate LSD/mescaline – bind to serotonin and dopamine
receptors hallucinations Prozac – enhances effect of serotonin by inhibiting
uptake after release Morphine, heroin – bind to endorphin receptors
decrease pain perception Viagra – increase NO (nitric oxide) effects maintain
erection Parkinson’s Disease – lack of dopamine Alzheimer’s Disease (AD) – develop senile plaques,
shrinkage of brain tissue
![Page 21: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/21.jpg)
Simple, automatic response to a stimulus Conscious thought not required Stimulus detected by receptor sensory
neuron interneuron (spinal cord) motor neuron cause effector (muscle or gland cell) to respond
![Page 22: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/22.jpg)
Gray matter
White
matter
Ventricles
![Page 23: Central nervous system (CNS)speedwaybiology.weebly.com/.../ap_biology_-_chapters_48_and_49_p… · Central nervous system (CNS) = brain + spinal cord Peripheral nervous system (PNS)](https://reader034.vdocuments.net/reader034/viewer/2022042713/5fabcd65c9d894787802d380/html5/thumbnails/23.jpg)
Structure Function
Brainstem *Oldest evolutionary part* Medulla oblongata – control breathing, circulatory
Cerebellum Motor, perception, cognitive functions
Thalamus Main center for sensory info
Hypothalamus Homeostasis (body temp, appetite, thirst, circadian rhythm, hormones), basic survival behaviors
Cerebrum Information processing (thinking, memory, personality, interpretation of sensory input)
Corpus callosum Connect hemispheres