Nervous System: electrochemical Flashcards
Central Nervous System (CNS)
made up of the brain and spinal cord; processes information and formulates responses
3 Main Parts of the Brain
cerebrum, cerebellum, brain stem
brainstem
connects the brain and spinal cord; controls involuntary movement(breathing); regulates the flow of information
cerebrum
responsible for voluntary and conscious activities; learning, judging, and intelligence
cerebellum
coordinates and balances the actions of muscles
coordination and balance (involuntary…kind of)
spinal cord
the link between the brain and the rest of the nerves in the body
interneurons
neurons that process information from sensory neurons and send messages to other interneurons or motor neurons
Where are interneurons found?
brain and spinal cord (CNS)
reflexes
quick, automatic responses to a stimulus
Pathway of a reflex
stimulus –> sensory receptor –> spinal cord —> effector —> response
Peripheral Nervous System (PNS)
gathers the information and sends to CNS, and carries the response
made up of nerves and other supporting cells
What are the two divisions of the PNS?
sensory and motor
Sensory nerves
carries the impulse that contains the information that the sensory receptor gathered
Motor nerves
carries the response from the CNS to effectors (glands and muscles)
Three types of stimuli/response pathways are…?
typical, eyes and ears, reflex
Typical Stimulus Response Pathway
stimulus —> receptor —> sensory nerves —> spinal cord then up spinal cord —> brain —-> down spinal cord —> motor nerves —> effectors —> response
Stimulus Response Pathway in eyes and ears
stimulus —> receptor —> sensory nerves —-> directly to brain —> down spinal cord —> motor nerves —> effectors —> response
Stimulus Response Pathway for reflexes
stimulus —> receptors —> sensory nerves —> spinal cord —> motor nerves —> effectors
(typically in response to danger)
Structure of a neuron
dendrites, cell body, axon, myelin sheaths, axon terminal
cell body of a neuron
contains the nucleus and other organelles
dendrites
carries impulse from other neurons/stimulus to the nerve cell body
axon
Carries impulse away from the nerve cell body and produces the neurotransmitters that cause a response
myelin sheaths
insulated membrane that surrounds a long axon with gaps
axon terminal
the end part of the axon where neurotransmitters leave
nodes
the gaps between myelin sheaths
neurotransmitters
Chemicals that transmit an impulse across the synapse
synapse
the space between two neuron cells or other cells
receptors
a transducer(device that converts something into another) that the neurotransmitter binds to
What is the nervous system’s way of communicating?
through impulses passed through nerves
(electrical and chemical, electrochemical)
Thermoregulation
the regulation of temperature within the body; negative feedback
What part of the brain senses changes in temperature for thermoregulation?
hypothalamus sends out signals to effectors
What is the response in the body if the body is decreasing in temp?
blood vessels constrict, muscles shiver to conserve heat and create heat
What is the response in the body if the body is increasing in temp?
blood vessels dilate (expand), sweat glands increase sweat production to cool off
Communication Method
endocrine vs. nervous
endocrine: chemical (hormones)
nervous: electrochemical (electrical and neurotransmitters)
Target of Stimulation
endocrine vs. nervous
endocrine: target cells
nervous: other neurons, muscles, glands
Speed of Response
endocrine vs. nervous
endocrine: relatively slower
nervous: very fast
Duration of Response
endocrine vs. nervous
endocrine: long-lasting (keeps going even after stimulus is gone)
nervous: short (seconds/milliseconds)
Area of Response
endocrine vs. nervous
endocrine: has an effect on the entire body (ex. lowers temp entire body)
nervous: specific localized areas (move only finger)
