Functional Advantage of the behavior Physiological Activity of brain and other organs Ontogenetic Process relating to development Evolutionary Historical influences of natural selection Advantages of Animal research Similarities to humans differences from humans evolutionary perspective ethics and limitations with humans Genes DNA RNA Hold information to build and maintain an organism s cell And pass traits to offspring consists of DNA that code for protein Instruction template isolated in cell nucleus Takes info out of cell nucleus and serves as a template for amino acid sequencing Proteins Become body tissues and functional components Chromosomes DNA that genes are composed of is tightly wound together come in pairs Genotype A set of gene alleles Phenotype The result of the expression of alleles referred to as a trait Homozygous Genes on each chromosome are identical RR rr Heterozygous Genes on each chromosome are different Rr Dominant Recessive Expressed traits will show through in either homozygous or heterozygous condition Expressed trait will ONLY show through in homozygous Condition Autosomes Not a sex determining chromosome Allosome Sex determining chromosome Sex Linked Found only on sex chromosome allosome Sex limited Found on autosome Mutation Neurons Nucleus Change in gene expression due to a change in DNA cells that specialized to receive and transmit information The structure that contains the chromosome Mitochondria Structures that preform metabolic activities and provide energy for the cell Ribosomes Sites at which the cell synthesizes new protein molecules Endoplasmic Reticulum Netork of thin tubes that transport newly synthesized proteins to their location Plasma Membrane a structure that separates the inside of the cell from the outside environment Nerve cell body Soma Dendrites Receive information Axon Send information Myelin Sheaths allows information to be conducted faster Nodes of Ranvier Spaces in between myelin sheaths Presynaptic Terminals End of axon where electrical action turns chemical Sensory Neurons Receives information send info to the rest of nervous system Interneurons Connects sensory to motor neurons within a single structure Motor Neurons Receives info from other neurons sends info to muscles Astrocytes group functionally similar terminals control blood flow glia Microglia immune cells of the nervous system removes wastes Oligodendrocytes build myelin sheaths on neurons of the brain and spinal cord Schwann Cells build myelin sheaths on neurons other than the brain and spinal cord Radial Glia guide placement of neurons during development then differentiate into other glia Blood Brain Barrier Pros Viruses can t get in cons it makes feeding brain costly Particles in solution want to diffuse and equally distribute Concentration Gradient Electrical Gradient Polarized Na K Pump Particles with opposite charges attract one another particles with the like charges repel charge differs from one side of the membrane to the other active transporting 3 NA go out for ever 2 K that moves into the cell Hyperpolarized Cell from outside to inside differs even more Depolarized Cell inside changes to become less polarized outside the cell is positive inside is negative changes to become more positive on the inside Threshold of excitation action potential is occurring Sets everything back to normal Sodium Potassium pump starts up Limit of Depolarization Refractory Period Presynaptic Cell Postsynaptic Cell Synaptic Cleft Space between individual neurons Neuron that releases the chemicals Receiving neuron Synapse Functional area between the two neurons Synthesis and Storage Most Neuron Transmitters made from amino acid Stored in vesicles Vesicles Release Spherical packets in presynaptic terminals Depolarization from action potential opens voltage gated Calcium Ca Channels in Presynaptic terminal Exocytosis Receptors Excitatory Inhibitory How does a Neuron Trans Mitter activate a Postsynaptic cell Neuron transmitters burst out of the end of the presynaptic terminal Found on membrane of postsynaptic cell lock key mechanism Increase probability that an action potential occurs Depolarization Decrease probability that an action potential will occur Hyperpolarization Changing the membrane potential alters permeability through changing configuration of ion channels Ionotropic Directly opens an ion channel last longer Metabotropic Activates a second messenger system that indirectly opens An ion channel Elimination Diffusion Degradation by enzymes Reuptake Recycled by transporters in membrane Autoreceptors Receptors found on presynaptic terminal that inhibit further NT release Glutamate NT Amino acid mainly excitatory GABA NT Amino acid mainly inhibitory Neuropeptides NT Large amino acid typically for use as modulators rather than having a direct effect Monoamines Similar to amino acid can be inhibitory or excitatory Catecholamines NT Monoamines Dopamine reward system Norepinephrine Alertness Indoleamines NT Monoamines Serotonin mood Acetylcholine NT Modified amino acid can be inhibitory or excitatory necessary for muscle contraction and many ways in brain memory attention Gases Purines Elliot NT Especially Nitric Oxide typically inhibitory but signals in a retrograde fashion backwards NT Modified nucleic acid ATP First to propose chemical communication application to smooth muscle Loewi Confirmed this with heart experiment Gap Junction Electrical synapses faster synchronization Neurotransmitters neuromodulators hormones Neurotransmitters Chemicals released into synapse at axons Neuromodulators Chemicals that are released into extracellular space by the dendrites of the presynaptic cell Hormones chemicals released into the blood by the endocrine glands directed by the hypothalamus brain region Neurons that directly secrete some hormones and control the secretion of others via releasing hormones Types of Chemicals used For communi cation Hypothalamus And posterior Pituitary Axon hillock Graded potential Multiple inputs coming from dendrites reflect the magnitude of the stimulus conducted throughout cell can be both excitatory or inhibitory EPSP IPSP Graded depolarization results from an influx of sodium ions Graded hyperpolatization results from chloride ions or sometimes efflux of potassium Reflux arc Consists of Sensory neuron interneurons Motor neurons Muscle fiber Temporal Summation Spatial Summation recurrent small stimulation to the same place Small stimulation to
View Full Document
Unlocking...