Exam 5 material Reviews Wednesday at 6 30pm in 100 Stillman Physiology Notes 2 10 14 Key Neurotransmitters Acetylcholine Ach o Rapidly destroyed by Ach esterase o Cognition behavior glands and organs Biogenic amines o Dopamine norepinephrine serotonin histamine o Brainstem and hypothalamus o Consciousness mood endocrine regulation Amino acids some excitatory others inhibitory Neuropeptides 2 aa s 2 or more amino acids chained together peptide endocrines and paracrines Both send signals from CNS to effector cells 6 46 Autonomic Somatic Somatic Neurons one Innervates Skeletal muscle voluntary movement Smooth muscle cardiac muscle glands GI neurons Result Excite cannot make things go in the opposite direction Excites and inhibits Autonomic two Autonomic Nervous System Purpose regulate automatic visceral responses o liver and kidney do their jobs without you having to tell them to do so o machinery behind the scenes work Method o Two opposing systems gas brakes o Sympathetic vs Parasympathetic Nervous System Most effectors innervated by both Cluster of cells ganglion not nucleus Parasympathetic vs Sympathetic Systems Function Ganglion Pre neurotransmitter S fight or flight aka gas P rest or regroup aka brake Spinal cord shorter Ach released Effector cord longer Ach released Post neurotransmitter Norepinephrine and Epinephrine Ach released Why do ganglion have to be in two separate locations Sympathetic subcategory o Adrenal Medulla Adrenaline comes from Adrenal Gland Inner art of adrenal gland Ganglion that releases to plasma endocrine gland Epinephrine and norepinephrine aka adrenaline Distant Organs Figure 6 44 Eye Example Lung Example Stimulus Pressure Temperature Light Sound Chemical Fight or flight response your pupils open up to allow light in that s why cartoon artists always make scared cartoons with huge eyes Rest and regroup gets the pupils contracted and back to normal once we calm down Contracting muscles make the tubes smaller rest and regroup Relaxing muscles makes the tubes bigger flight or fight Sensory Nervous System Afferent Nervous System Purpose detect and relay info about environment to CNS Stimulus Receptor Afferent neuron s Receptor Afferent axon terminal s or specialized cells Specific to stimulus type Produce receptor potentials Afferent neuron Generate APs Convery info to CNS Sensory Receptors Figure 7 1 Two designs 1 Directly by neuron end faster 2 Receptor cell to neuron end slower See more of this type than the direct neuron end method Having a second cell allows us to make lots of changes to how this cell is made up allows us to make specialized adjustments in order to create specialized cells The second cells allows us to do more changes Speed difference more steps slower Types of receptor cells are specific but not o Mechanoreceptors pressure or stretch o Thermoreceptors temperature o Photoreceptors light waves AKA photons o Chemoreceptors chemicals o Nocicceptors painful stimuli heat or tissue damage 2 12 14 Sensory Receptors continued 7 2 Coding intensity location sensory transduction o Intensity are you standing next to a bonfire because there is heat o Location is it my left hand or my right hand want to go away from the intense heat Changing sense into a message Variable stimulus Variable receptor potentials GPs Variable AP pattern not magnitude Variable NT amount o Increase stimulus o Increase AP frequency o Increase number of NTs If you want to travel distance turn greater potentials into action potentials o Voltage gated sodium and potassium channels excitable cell Coding intensity location sensory transduction 1 Receptive field area covered 7 4 and 7 6 Size related to localizing narrow is more specific smaller is better Density related to sensitivity more receptors in the finger tips then in other areas of the body which is why fingers are able to feel pressure better o Higher density better sensitivity Overlap possible get recruitment 7 8 o Venn diagram A B and C areas take out intersection pieces so that only B responds helps localization stimulus only in area where there is lack of overlap 2 Lateral inhibition sharpens the pattern contrast Impacting neighbors in a negative way 7 9 Crossing over hyperpolarizes ALL are inhibited When you scratch a mosquito bite it stops itching Processing 7 14 Ascending pathway in CNS o Brain stem thalamus cerebrum with cross Things happening on the left hand get registered on the right side of the brain o To specific brain regions Visual auditory taste o Thermo and mechanoreceptors o Nociceptors detects pain detect products of damaged and immune cells Input can be impacted by output Somatosensory System Info skin muscles bones tendons joints Type free or modified afferent terminals Components Spatially related positioning in brain 7 20 o Cortical projection o AKA homunculus means little man o Changes but limited 2 14 14 Auditory System Info sound waves Type stereocilia o AKA cochlear hairs o Mechanoreceptors Components path for sound 7 37 o External auditory canal o Tympanic membrane aka eardrum o Middle ear air o Cochlea water looks like a snail o auditory nerves Cochlea encodes wave 7 41 o Mechanical bending of stereocilia middle ear and cochlea are proportional with each other the bigger the air way the bigger the water way mechanically gated K and Ca 2 key in process o What s coded Amplitude loudness amount of bend Frequency pitch which stereocilia pick up the bend more waves higher ptitch high frequency near base of cochlea low frequency near apex of cochlea 7 38 baby s pick up higher pitch better because of small cochlea o What s missing DIRECTION LOCATION of sound Location in space of source Vestibular System Info head position and motion Type stereocilia 7 44 Components o Semicircular canals 3 7 42 Rotation with direction But need a reference o Utricle and saccule with otoliths Acceleration relative to gravity 7 46 Usefulness o Visual tracking o Basic Coordination and spatial recognition
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