Neurobiology: The Functioning of Neurons and Neuroglia, Quizzes of Biology

Download Neurobiology: The Functioning of Neurons and Neuroglia and more Quizzes Biology in PDF only on Docsity! TERM 1 The path of the impulse DEFINITION 1 Sensory recptorsensory neuronassociation neuronsCNS TERM 2 Motor neurons DEFINITION 2 Carries impulses from the association neurons to the effectors(muscles and glands) TERM 3 The 3 general types of neurons DEFINITION 3 MotorAssociationSensory TERM 4 Constitutes the peripheral nervous sytem DEFINITION 4 Sensory and motor neurons TERM 5 somatic neurons DEFINITION 5 Motor neurons that stimulate the skeletal muscles to contract. TERM 6 Autonomic motor neurons DEFINITION 6 Motor neurons that regulate the activities of the smooth muscle, cardiac muscle, and glands. TERM 7 2 subdivisions of the autonomic motor neurons DEFINITION 7 sympathetic systemParasympathetic system TERM 8 Dendrites DEFINITION 8 Cytoplasmic extensions that extend from the neuron cell body. They are the receiving portion of a neuron. TERM 9 Dendritic spines DEFINITION 9 extensions of dendrites that increase the surface area of the plasma membrane. TERM 10 Neuroglia cells DEFINITION 10 structurally a dn functionally support Neurons. they are 10x more numerousthan neurons. They serve a variety of functions, including supplying neurons with nutrients, removing wastes from neurons, guiding axon migration, and providing immune functions. TERM 21 resting membrane potential DEFINITION 21 When a neuron is not being stimulated, it maintains what is referred to as a resting membrane potential. If measured with a voltmeter, this resting potential equals about -70 millivolts it is due to the combined activities of the fixed anions, the sodium- potassium pump, and the membrane leak channels that an electro-chemical equilibrium or resting membrane potential is established TERM 22 have the greatest influence on establishing the resting membrane potential of a cell DEFINITION 22 Potassium ions (K+)IF K+ was the only ion involved in establishing the resting potential, the potassium ions would equilibrateat a resting membrane potential of -90 mv TERM 23 Point where K+ will diffuse out of a cell DEFINITION 23 membrane potentials less negative than -90 mv (e.q., -80 mv) At membrane potentials more negative than -90 mv (e.q., -100 mv) K+ will diffuse into the cell. TERM 24 resting membrane potential of a typical mammalian neuron DEFINITION 24 -70 mv Its largely the effects of Na+that makes the resting membrane potential of a typical mammalian neuron -70 mv rather than -90 mv TERM 25 equilibrium potential of Na+ DEFINITION 25 +60 mv. as Na+moves into the cell, the membrane potential moves further away from that of the potassium equilibrium point; and thus as mentioned above, K+ diffuses out of the cell. TERM 26 graded potentials DEFINITION 26 While all cells maintain resting potentials across their plasma membranes, neurons and muscle cells are unique because their membrane potentials can be stimulated to undergo rapid, temporary changes TERM 27 In neurons, graded potentials are caused by the activation of specialized membrane transport proteins called DEFINITION 27 gated ion channels. These channels are closed at the cells resting membrane potential. TERM 28 gated ion channels. DEFINITION 28 gated ion channels can be stimulated to open by various stimuli (e.g., chemicals, light, heat); These channels are closed at the cells resting membrane potential. Once they are open, the gated ion channels allow specific ions to pass through them and in doing so they affect a local alteration of the neurons membrane potential. TERM 29 receptor potential. DEFINITION 29 gated ion channels can be stimulated to open by various stimuli (e.g., chemicals, light, heat); and when they open they trigger a graded potential called a receptor potential. TERM 30 hyperpolarization DEFINITION 30 more negative Hyperpolarization (becoming more negative = becoming less positive) moves the cell further from the membrane potential required to initiate an action potential. TERM 31 depolarization DEFINITION 31 more positive Depolarization (becoming more positive = becoming less negative) brings a neuron closer to threshold from its resting potential of -70 mv. TERM 32 summation DEFINITION 32 local variations in membrane potential can combine or cancel one another out in a process referred to as summation TERM 33 threshold DEFINITION 33 the level of depolarization needed to produce an action potential or nerve impulse. -55 mv TERM 34 Voltage-gated ion channels DEFINITION 34 a special type of membrane channel found in muscle cells and neurons. They are protein channels that have gates that open a pore in the channel at specific membrane potentials (voltages). TERM 35 peak depolarization DEFINITION 35 typically a peak depolarization of +30 mv will have been reached TERM 46 acetylcholinesterase (AChE) DEFINITION 46 The elimination of ACh from the synaptic cleft is achieved by an enzyme in the postsynaptic plasma membrane called acetylcholinesterase (AChE). AChE quickly cleaves the acetylcholine into inactive fragments. "nerve gas" and the insecticide Parathion are both potent AChE inhibitors. TERM 47 Glutamate DEFINITION 47 the major excitatory neurotransmitter in the vertebrate CNS. TERM 48 inhibitory neurotransmitters. DEFINITION 48 Glycine and GABA (gamma-aminobutyric acid) are inhibitory neurotransmitters. These neurotransmitters cause chemically gated ion channels for Cl- to open TERM 49 biogenic amines DEFINITION 49 hormone epinephrine (adrenaline) as well as the neurotransmitters dopamine, norepinephrine, and serotonin.A biogenic amine is a biogenic substance with an amine group. TERM 50 derived from the amino acid tyrosine. DEFINITION 50 Epinephrine, norepinephrine, and dopamine TERM 51 derived from the amino acid tryptophan. DEFINITION 51 Serotonin TERM 52 Dopamine DEFINITION 52 is a neurotransmitter used in the brain to control body movements and other functions. TERM 53 Serotonin DEFINITION 53 a neurotransmitter involved in the regulation of sleep and it also plays a role in establishing various emotional states. TERM 54 Endorphins DEFINITION 54 released by neurons in the brain stem, block the perception of pain. TERM 55 produced from the amino acid arginine. DEFINITION 55 Nitric oxide (a gas)Nitric oxide acts by causing the relaxation of smooth muscles associated with various blood vessels to cause vasodilation. The drug sildenafil (Viagra) increases the release of NO in the penis and thus prolongs the engorgement of the penis with blood that causes penile erection.