chapter 2: nervous system Flashcards
central nervous system
•consists of the brain and spinal cord
•sends and receives messages to and from the PNS
brain function
•receives and processes sensory information
•coordinates a response to that information
spinal cord function
•connects the brain to the PNS
•receives sensory information from the PNS and sends to the brain (up the spinal cord)
•receives motor information from the brain and sends it to various parts of the body using PNS (down the spinal cord)
S.A.M.E
Sensory
Afferent
Motor
Efferent
peripheral nervous system
•entire network of nerves outside the CNS
•carries sensory information to the CNS
•carries motor information from the CNS
somatic nervous system
•carries sensory information from sensory receptors to the CNS (afferent/ towards)
•carries motor information from the CNS (efferent/away from) to our skeletal muscles to response and control skeletal movements/activity.
autonomic nervous system
•connects CNS to internal organs and glands
•self-regulating that occurs without conscious effort.
•under non-voluntary control
•automatic
sympathetic nervous system
•prepares body for action (stimulates)
•fight flight freeze response
•triggers stressor/fear response
•heart, blood and breathing rates increase
•releases of hormones such as adrenaline, cortisol
•energises the body, glands and muscles for potential threat.
parasympathetic nervous system
•counterbalancing the activities of of the sympathetic NS
•helps maintain the body’s internal environment (homeostasis) in a steady balanced state (peace)
•restores the body to a state of calm after nervous activation has passed
•takes while for body to return to normal state as it has to remove the hormones from bloodstream
sympathetic reactions response
•increases release of blood glucose
•stimulate release of hormones (adrenal glands)
•dialated pupils
•expanded lungs to increase breathing rate
•heart rates increasing
•decreased stomach/intestines contractions related to digestion
parasympathetic reactions response
•heart rate decreases
•breathing rates decreases
•increases salivation
•decreases the release of glucose into bloodstream
•release of hormones are decreased
•pupils contract
•stomach/intestines contractions increased
conscious response
•reaction to a sensory stimulus that involves awareness and is voluntary (intentional)
•happens after you have paid attention to the stimulus
unconscious response
•reaction to a sensory stimulus that doesn’t involve awareness and is involuntary/automatic (unintentional)
•controlled by autonomic NS
•sometimes are reflexive responses ( autonomic reflexes) in situations where there isn’t enough time to make a conscious response
enteric nervous system
the gastrointestinal tract that is part of the digestive system that comprises the hollow organ that food and liquids are swallowed, digested and absorbed
spinal reflex
•an unconscious, involuntary response that occurs automatically to certain stimulus without involvement of the brain.
•allows faster reaction time in harmful situations
neuron
•is an individual nerve cell that is specialised to receive, process and transmit information to other cells in the body
neurotransmitter
•is a chemical substance produced by a neuron that carries a message to other neurons or cells
•neurons that release neurotransmitters is called presynaptic neuron,
•once released they attach themselves to receptor sites of postsynaptic neuron
excitatory effect
•some neurotransmitters have excitatory effects that can stimulate or activate postsynaptic neurons to preform their functions (firing)
inhibitory effect
•other neurotransmitters have inhibitory effect that block or prevent post synaptic neurons from firing
glutamate (Glu)
•main excitatory neurotransmitter in CNS
•enhances information transmission
•post synaptic neurons more likely to fire
•increases learning and memory
gamma-amino butyric acid (GABA)
•main inhibitory neurotransmitter in the CNS
•opposite of glutamate
•it works through the brain to make the post synaptic neurons less likely to fire
S.A.M.E
Sensory
Afferent
Motor
Efferent
“glutamate”=__ “GABA”=__
“go” and “slow”
neuromodulators
•known to modulate or influence the effects of other neurotransmitters
•can change the reactivity of receptors to enhance their excitatory or inhibitory responses
•make them more or less potent
•doesn’t only release in synapses
•can release into far broader areas and affect number of neurons
