Sinh học - Chương 43: Review warm up

Ch. 43 Review Warm-UpContrast the functions of B cells and T cells.What are memory cells?How do vaccines work?How does HIV affect the immune system?Warm-UpDraw and label the parts of a neuron.Describe saltatory conduction.Explain how a nerve impulse is transmitted across a neuron.Warm-UpWhat happens at the synapse?Choose 1 neurotransmitter. Describe its action.What is the role of the following structures in the human brain?BrainstemCerebellumCerebrumCorpus callosumNervous SystemsChapters 48 & 49Campbell Biology – 9th ed.You must knowThe anatomy of a neuron.The mechanisms of impulse transmission in a neuron.The process that leads to release of neurotransmitters, and what happens at the synapse.How the vertebrate brain integrates information, which leads to an appropriate response.Different regions of the brain have different functions.Organization of the Nervous SystemCentral nervous system (CNS) = brain + spinal cordPeripheral nervous system (PNS) = nerves throughout bodySensory receptors: collect infoSensory neurons: body  CNSMotor neurons: CNS  body (muscles, glands)Interneurons: connect sensory & motor neuronsNerves = bundles of neuronsContains motor neurons +/or sensory neuronsPeripheralnervous systemSomaticnervoussystemAutonomicnervoussystemSympatheticdivisionParasympatheticdivisionEntericdivisionPeripheral Nervous SystemNeuron = dendrite + cell body + axonNeuroncell body: contains nucleus & organellesdendrites: receive incoming messagesaxons: transmit messages away to other cellsmyelin sheath: fatty insulation covering axon, speeds up nerve impulsessynapse: junction between 2 neuronsneurotransmitter: chemical messengers sent across synapseGlia: cells that support neuronsEg. Schwann cells (forms myelin sheath)Schwann cells and the myelin sheathMake a Mad, Mad, Mad NeuronBioFlix: How Neurons WorkMembrane Potential: difference in electrical charge across cell membrane MicroelectrodeReferenceelectrodeVoltagerecorder–70 mVThe Na+/K+ pump (using ATP) maintains a negative potential inside the neuron.Action potentials (nerve impulses) are the signals conducted by axonsResting potential: membrane potential at rest; polarizedNa+ outside, K+ inside cellVoltage-gated Na+ channel = CLOSEDNerve impulse: stimulus causes a change in membrane potentialAction potential: neuron membrane depolarizesAll-or-nothing responseNa+ channels openNa+ enters cellK+ channels openK+ leaves cellConduction of an action potentialNerve Impulse AnimationSaltatory conduction: nerve impulse jumps between nodes of Ranvier (unmyelinated gaps)  speeds up impulseSaltatory conduction speed: 120 m/secBioFlix: How Synapses WorkCell communication: neurotransmitter released at synapsesAxon (presynaptic cell)  Dendrite (postsynaptic cell)NeurotransmittersChemicals released from vesicles by exocytosis into synaptic cleftDiffuse across synapseBind to receptors on neurons, muscle cells, or gland cellsBroken down by enzymes or taken back up into surrounding cellsTypes of neurotransmitters:Excitatory: speed up impulses by causing depolarization of postsynaptic membraneInhibitory: slow impulses by causing hyperpolarization of postsynaptic membraneExamples of NeurotransmittersAcetylcholine (ACh): stimulates muscles, memory formation, learningEpinephrine: (adrenaline) fight-or-flightNorepinephrine: fight-or-flightDopamine: reward, pleasure (“high”)Loss of dopamine  Parkinson’s DiseaseSerotonin: well-being, happinessLow levels  DepressionGABA: inhibitory NTAffected by alcoholNervous System DisordersLSD/mescaline – bind to serotonin and dopamine receptors  hallucinationsProzac – enhances effect of serotonin by inhibiting uptake after releaseMorphine, heroin – bind to endorphin receptors  decrease pain perceptionViagra – increase NO (nitric oxide) effects  maintain erectionAlzheimer’s Disease (AD) – develop senile plaques, shrinkage of brain tissueMouse PartyMouse PartyPoster Presentation:Drug:Neurotransmitter(s) InvolvedAction of Drug:Summary IllustrationReflexesSimple, automatic response to a stimulusConscious thought not requiredReflex arc:Stimulus detected by receptorSensory neuronInterneuron (spinal cord or brain stem)Motor neuronResponse by effector organ (muscles, glands)Knee-jerk reflexEvolution of Nervous SystemsVertebrate brain is regionally specializedMajor Regions: forebrain, midbrain, hindbrainForebrain  cerebrumMidbrain  brainstemHindbrain  cerebellumHuman BrainStructureFunctionCerebrumInformation processing (learning, emotion, memory, perception, voluntary movement)Right & Left cerebral hemispheresCorpus callosum: connect hemispheresBrainstem*Oldest evolutionary part*Basic, autonomic survival behaviorsMedulla oblongata –breathing, heart & blood vessel activity, digestion, swallowing, vomitingTransfer info between PNS & CNSCerebellumCoordinate movement & balanceMotor skill learningStructureFunctionCerebrumInformation processing (learning, emotion, memory, perception, voluntary movement)Right & Left cerebral hemispheresCorpus callosum: connect hemispheresBrainstem*Oldest evolutionary part*Basic, autonomic survival behaviorsMedulla oblongata –breathing, heart & blood vessel activity, digestion, swallowing, vomitingTransfer info between PNS & CNSCerebellumCoordinate movement & balanceMotor skill learningHuman BrainStructureFunctionCerebrumInformation processing (learning, emotion, memory, perception, voluntary movement)Right & Left cerebral hemispheresCorpus callosum: connect hemispheresBrainstem*Oldest evolutionary part*Basic, autonomic survival behaviorsMedulla oblongata –breathing, heart & blood vessel activity, digestion, swallowing, vomitingTransfer info between PNS & CNSCerebellumCoordinate movement & balanceMotor skill learningHuman BrainStructureFunctionCerebrumInformation processing (learning, emotion, memory, perception, voluntary movement)Right & Left cerebral hemispheresCorpus callosum: connect hemispheresBrainstem*Oldest evolutionary part*Basic, autonomic survival behaviorsMedulla oblongata –breathing, heart & blood vessel activity, digestion, swallowing, vomitingTransfer info between PNS & CNSCerebellumCoordinate movement & balanceMotor skill learningHuman BrainGrey matter: neuron cell bodies, unmyelinated axonsWhite matter: fatty, myelinated axonsDiscovery Video: Teen Brains