Week 7 Flashcards
brain stem
controls most vital pieces
what are the three parts of the brain stem?
medulla, pons, midbrain
what are the functions of the brain stem?
respiration, circulation and digestion (swallowing)
cerebellum
controls movement, balance and coordination and muscle tone
diencephalon
thalamus and hypothalamus
thalamus
major relay station, crude level of motor control and sensation
hypothalamus
homeostatic regulation, links nervous and endocrine systems
cerebrum
made up of basal nuclei and cerebral cortex
what part of the brain makes up 80% if the weight?
cerebrum
what are the parts of the cerebral cortex?
matters (grey and white), corpus callosum, and ventricles
what makes up grey matter?
clusters of cell bodies, mainly on the outside
what makes up white matter?
myelinated axons, mainly on the inside
what is the corpus callosum?
large bundle of axons that connect the two hemispheres
what are the ventricles?
fluid-filled chambers,
what is a common cause of headaches?
not enough fluid in the ventricles
what are the functions of the cerebral cortex?
perception, voluntary movement, language, learning/memory
what makes up the forebrain?
cerebrum and diencephalon
what protects the spinal cord?
vertebrae + their processes
what is the main cause of damage to the spinal cord?
repetitive twisting motions
what makes up the spinal cord?
grey (middle) and white matter (inside)
what makes up the grey matter of the spinal cord?
interneurons and parts of efferent and afferent neurons
what makes up the white matter of the spinal cord?
axons leaving and entering the CNS
what does “DAVE” mean
dorsal -> afferent, ventral -> efferent
what is the most commonly used neurotransmitter?
acetylcholine (ACh)
why is acetylcholine rapidly destroyed by ACh-esterase?
cleaned up quickly to have distinct messages
what is acetylcholine typically used for?
messages relating to cognition, behavior, control of glands and organs
what are some examples of biogenic amines?
dopamine, norepinephrine, epinephrine, serotonin, histamine
what are biogenic amines typically used for?
messages relating to consciousness, mood and endocrine regulation
are amino acids used as neurotransmitters?
yes
what are neuropeptides?
2+ amino acids linked together
what can neuropeptides act as?
neurotransmitters, paracrines and endocrines
what are the two parts of the efferent nervous system?
autonomic and somatic
what do the autonomic and somatic nervous systems have in common?
both send signals from CNS to effectors
how many neurons does it take to reach the effector in the autonomic nervous system?
2
how many neurons does it take to reach the effector in the somatic nervous system?
1
what does the autonomic NS innervate?
skeletal muscles (voluntary)
what does the somatic nervous system innervate?
smooth and cardiac muscle, glands and digestive tract
what is the function of the autonomic nervous system?
regulate automatic or visceral acts, CNS to effectors
what are the two systems of the autonomic NS?
sympathetic and parasympathetic
what are clusters of the 2nd cell bodies?
ganglia
preganglionic
cell body in the CNS
postganglionic
after the ganglia
what system controls “fight or flight?”
sympathetic
what system controls “rest or regroup?”
parasympathetic
which system typically moves us away from set point?
sympathetic
which system typically moves us towards from set point?
parasympathetic
where are the sympathetic ganglia?
near the spine, preganglionic neuron is shorter
where are the parasympathetic ganglia?
closer to the effectors, preganglionic is longer
preganglionic neurotransmitters (symp and parasymp)
acetylcholine
postganglionic neurotransmitters in sympathetic
epinephrine and norepinephrine
postganglionic neurotransmitters in parasympathetic
acetylcholine
what is the special case in the sympathetic nervous system?
adrenal medulla
where is the adrenal medulla
inner part of the adrenal gland
what is special about the adrenal medulla?
postganglionic neurons release endocrines into the plasma (adrenaline)
what is adrenaline? what is noradrenaline?
epinephrine, norepinephrine
what is the effect of adrenaline?
widespread and longer lasting message, important in life or death situations
what does the sympathetic nervous system do to pupils?
dilate them
what does the sympathetic nervous system do to cardiac output?
increase HR
what does the sympathetic nervous system do to bronchioles?
relax the surrounding muscles, increases diameter to take in more oxygen
what does the sympathetic nervous system do to digestive activity?
decrease, saving energy
what does the parasympathetic nervous system do to pupils?
contract them
what does the parasympathetic nervous system do to cardiac output?
decrease HR
what does the parasympathetic nervous system do to bronchioles?
contract muscles, decreasing diameter
what does the parasympathetic nervous system do to digestive activity?
increase it
sensory nervous system
detect and relay info to the CNS
stimulus
detectable change
modalities
heat, light, pressure, chemicals
photoreceptors
light
mechanoreceptors
pressure, stretch
thermoreceptors
heat, cold
osmoreceptors
concentration of solutes in ECF
chemoreceptors
concentration of a solute
noiceceptors
tissue damage (pain)
1st receptor design
afferent nerve receiving signals (faster)
2nd receptor design
receptor cells sends message to afferent nerve (more common)
what is the benefit of the 2nd receptor design?
cell devoted to detecting. stimulus is more precise in collecting information
sensory transduction
key info coded for CNS, intensity/location
what are the key parts of location coding?
type of receptor, receptive field and lateral inhibition
what is lateral inhibition?
sharpen contrast by inhibiting neighboring signals
what is the receptive field?
area covered by axon terminal, sometimes overlapping
