front 1 Neuronal pools | back 1 Functional groups of neurons that process and ingrate information. |
front 2 Sodium-potassium (Na+-K+) pump | back 2 A primary active transport system that simultaneously drives Na+ out of the cell against a s steep gradient and pumps K+ back in. Also called Na+-K+ ATPase. |
front 3 Involuntary nervous system | back 3 The autonomic nervous system |
front 4 Acetylcholinesterase (AChE) | back 4 Enzyme present at the neuromuscular junction and synapses that degrades acetylcholine and terminates its action. |
front 5 Peripheral nervous system (PNS) | back 5 Portion of the nervous system consisting of nerves and ganglia that lie outside of the brain and spinal cord. |
front 6 Nerve growth factor (NGF) | back 6 Protein that promotes survival and development of neurons; secreted by their target cells and many other cell types. |
front 7 Dendrite | back 7 Branching neuron process that serves as a receptive, or input, region; transmits an electrical signal toward the cell body. |
front 8 Synapse | back 8 function junction or point of close contact between two neurons or between a neuron and an effector cell. |
front 9 Nucleus | back 9 (1) control center of a cell; contains genetic material; (2) clusters of nerve cell bodies in the CNS. |
front 10 Conductivity | back 10 Ability to transmit an electrical impulse. |
front 11 Summation | back 11 Accumulation of effects those of muscular, sensory, or mental stimuli. |
front 12 Oligodendrocyte | back 12 A type of CNS supporting cell that composes myelin sheaths. |
front 13 Glial cells | back 13 Non-excitable cells of neural tissue that support, protect, and insulate, the neurons. See Neuroglia.. |
front 14 Axon | back 14 Neuron process that carries impulses away from the nerve cell body; efferent process; the conducting portion of a nerve cell. |
front 15 Axon terminals (terminal boutons) | back 15 The bulbous distal endings of the terminal branches of an axon. |
front 16 Microglial cells | back 16 A type of CNS supporting cell; can transform into phagocytes in areas of neural damage or inflammation. |
front 17 Synaptic cleft | back 17 fluid filled space at a synapse. |
front 18 Multiple sclerosis (MS) | back 18 Demyelinating disorder of the CNS; causing hardened patches (sclerosis) in the brain and spinal cord. |
front 19 Afferent (sensory) nerve | back 19 Nerve that contains processes of sensory neurons and carries nerve impulses to the central nervous system. |
front 20 Excitatory postsynaptic potential (EPSP) | back 20 Depolarizing graded potential in a postsynaptic neuron. |
front 21 Reflex | back 21 Automatic reaction to stimuli. |
front 22 Excitability (responsiveness) | back 22 Ability to respond to stimuli. |
front 23 White matter | back 23 White substance of the central nervous system; myelinated nerve fibers. |
front 24 Catecholamines | back 24 Epinephrine, norepinephrine, and dopamine; a class of amines that act as chemical transmitters. |
front 25 Nervous System | back 25 Fast-acting control system that triggers muscle contraction or gland secretion. |
front 26 Inhibitory postsynaptic potential (IPSP) | back 26 A graded potential in a postsynaptic neuron that inhibits action potential generation; usually hyperpolarizing. |
front 27 Myelin sheath | back 27 Fatty insulating sheath that surrounds all but the smallest nerve fibers. |
front 28 Salutatory conduction | back 28 Transmission of an action potential along a myelinated fiber in which the nerve impulse appears to leap from gap to gap. |
front 29 Bipolar neuron | back 29 Neuron with axon and dendrite that extend from opposite sides of the cell body. |
front 30 Action potential | back 30 A large transient depolarization event, including polarity reversal, that is conducted along the membrane of a muscle cell or a nerve fiber. |
front 31 Unipolar neuron | back 31 Neuron in which embryological fusion of the two processes leaves only one process extending from the cell body. |
front 32 Interneuron (association neuron) | back 32 Nerve cell located between motor and sensory neurons that shuttles signals through CNS pathways where integration occurs. |
front 33 Synaptic delay | back 33 Time required for an impulse to cross a synapse between two neurons. |
front 34 Resting membrane potential | back 34 Resting membrane potential: the voltage that exists across the plasma membrane during the resting state of an excitable cell; ranges from -90 to -20 millivolts depending on cell type. |
front 35 Schwann cell | back 35 A type of supporting cell in the PNS; forms myelin sheaths and is vital to peripheral nerve fiber regeneration. |
front 36 Terminal Branches | back 36 Branching ends of an axon that allow it to form many axon terminals; telodendria. |
front 37 Nerve Impulse | back 37 A self-propagating wave of depolarization; also called an action potential. |
front 38 Neuroglia | back 38 Non-excitable cells of neural tissue that support, protect, and insulate the neurons; glial cells. |
front 39 Axolemma | back 39 The plasma membrane of an axon |
front 40 Efferent | back 40 Carrying away or away from, especially a nerve fiber that carries impulses away from the central nervous system. |
front 41 Graded potential | back 41 A local change in membrane potential that varies directly with the strength of the stimulus, declines with distance. |
front 42 Neurotransmitter | back 42 Chemical messenger released by neurons that may, upon binding to receptors of neurons or effector cells, stimulate or inhibit those neurons or effector cells. |
front 43 Neuropeptides | back 43 A class of neurotransmitters including beta endorphins and enkephalins (which act as euphorics and reduce perception of pain) and gut-brain peptides. |
front 44 Nitric oxide (NO) | back 44 A gaseous chemical messenger; diverse functions include participation in memory formation in the brain, and causing vasodilation throughout the body. |
front 45 Innervation | back 45 Supply of nerves to a body part. |
front 46 Afferent | back 46 Carrying to or toward a center. |
front 47 Depolarization | back 47 Loss of a state of polarity; loss or reduction of negative membrane potential. |
front 48 Astrocyte | back 48 A type of CNS supporting cell; assists in exchanges between blood capillaries and neurons. |
front 49 Integration | back 49 The process by which the nervous system processes and interprets sensory input and makes decisions about what should be done at each moment. |
front 50 Central nervous system (CNS) | back 50 Brain and spinal cord. |
front 51 Voluntary nervous system | back 51 The somatic nervous system. |
front 52 Acetylcholine (ACh) | back 52 Chemical transmitter substance released by some nerve endings. |
front 53 Hyperpolarization | back 53 An increase in membrane potential in which the membrane becomes more negative than resting membrane potential. |
front 54 Parasympathetic division | back 54 The division of the autonomic nervous system that oversees digestion, elimination, and glandular function; the resting and digesting subdivision. |
front 55 Psuedounipolar neuron | back 55 Another term for unipolar neuron. |
front 56 Ependymal cell | back 56 A type of CNS supporting cell; lines the central cavities of the brain and spinal cord. |
front 57 Sympathetic division | back 57 The division of the autonomic nervous system that prepares the body for activity or to cope with some stressor (danger, excitement, etc..); the fight. fright, and flight subdivision. |
front 58 Relative refractory period | back 58 Follows the absolute refractory period interval when a threshold for action potential stimulation is markedly elevated. |
front 59 Nerve | back 59 A bundle of axons in the peripheral nervous system. |
front 60 Somatic nervous system | back 60 division of the peripheral nervous system that provides the motor innervation of skeletal muscles; also called the voluntary nervous system. |
front 61 Absolute refractory period | back 61 Period following stimulation during which no additional action potential can be evoked. |
front 62 Synaptic vesicles | back 62 Small membranous sacs containing neurotransmitter. |
front 63 Multipolar neurons | back 63 Neurons with three or more processes; most common neuron type in the CNS. |
front 64 Neuron (nerve cell) | back 64 Cell of the nervous system specialized to generate and transmit electrical signals (action potentials and graded potentials). |
front 65 Nerve Fiber | back 65 Axon of a neuron |
front 66 Electrochemical gradient | back 66 To combined difference in concentration and charge; influences the distribution of diffusion of ions |
front 67 Neuron cell body | back 67 The biosynthetic center of a neuron; also called the perikaryon, or soma. |