Term
|
Definition
| an electrical potentioal created by the separation of charged ions, measured in volts. |
|
|
Term
|
Definition
| Net flow of charge. (positive current flows in the direction of positive charges) |
|
|
Term
|
Definition
| a measure of the ease of current flow between two points. G=1/R, measured in siemens |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Stores energy in an electric field. A device that can separate charge. Phospholipid bilayer is an example of a capacitor. |
|
|
Term
| True or False: Voltage across the membrane is central to the behavior of excitable cells. |
|
Definition
|
|
Term
|
Definition
| the voltage at which there is no net movement of a specific ion through an open conductance. (Eion) Every permeant has its own equilibrium potential. |
|
|
Term
| Two driving forces that set the equilibrium potential of an ion: |
|
Definition
| the chemical gradient and the electric gradient |
|
|
Term
| True or False: If both sides of the membrane are electrically neutral there is no voltage across the cell. |
|
Definition
|
|
Term
| True or False: Ion transporters do not require energy to move ions against their electrochemical gradient. |
|
Definition
| False: they do require energy |
|
|
Term
| Electrochemical equilibrium |
|
Definition
| When the concentration gradient is equal and opposite to the voltage gradient. |
|
|
Term
|
Definition
Predicts equilibrium potential.
Eion=(RT/ZionF)ln([ion]out/[ion]in) |
|
|
Term
| True or False: Having a membrane potential means the entire inside of the cell is chared with respect to the outside. |
|
Definition
| False: In reality, the membrane potential is an electric field across the membrane only. Bulk solutions are neutral in charge. |
|
|
Term
Equilibrium Potential of an ion
AKA |
|
Definition
|
|
Term
| Resting Membrane Potential |
|
Definition
| The voltage across the membrane of a cell at rest. Also, the weighted avg. of the equilibrium potentials for all permeant ions. |
|
|
Term
| Resting Membrane Potential |
|
Definition
| The voltage across the membrane of a cell at rest. Also, the weighted avg. of the equilibrium potentials for all permeant ions. |
|
|
Term
| Weighting Factor in determining the resting membrane potential |
|
Definition
|
|
Term
| Resting Potential of a cell |
|
Definition
|
|
Term
|
Definition
| Calculates the voltage across a membrane permeable to more than one ion |
|
|
Term
| True or False: A resting membrane has a relatively low permeability to K+. |
|
Definition
| False: has a high permeability |
|
|
Term
| True or False: Increases in extracellular K+ depolarizes the neuron. |
|
Definition
|
|
Term
| True or False: At rest a neuron has high permeability to Na+. |
|
Definition
| False: it has low permeability at rest |
|
|
Term
|
Definition
| A brief, regenerative, all or noe, electrical potential that originates in a neuronal cell body and propogates down an axon. |
|
|
Term
| True or False: Signalling between cells is both electrical and chemical. |
|
Definition
|
|
Term
| Early misinterpretations of Action Potentials (Bernstein) |
|
Definition
Membrane was thought to be exclusively permeable to K+ at rest.
Thought the same became more positive when excited, moving from -60mv to 0mv.
Thought that when excited membrane became permeable to all ions. |
|
|
Term
|
Definition
| First demonstrated action potentials were dependent of external Na+ ions. |
|
|
Term
| Overshoot of an Action potential proves... |
|
Definition
| that it can't just be a general hole in the membrane in which any ion can pass |
|
|
Term
| When ecternal Na+ is removed |
|
Definition
| There is no Action Potential generated |
|
|
Term
| True or False: Permeability of ions changes during an action potential. |
|
Definition
|
|
Term
| True or False: At rest the permeability of Na+ is much greater than the permeability of K+. |
|
Definition
|
|
Term
| During an action potential the permeability of which ion increases across the membrane? |
|
Definition
|
|
Term
|
Definition
| the voltage at which an all-or-none action potential in initiated |
|
|
Term
|
Definition
| Created the voltage clamp in 1949. Studied the effect of voltage on conductance. |
|
|
Term
Voltage is the driving Force.
Modification of Ohm's law. |
|
Definition
|
|
Term
|
Definition
| four voltage sensitive gating particles that form K+ channels. (The Hodgkin Huxley Model) |
|
|
Term
| Na+ current: Hodgkin Huxley Model |
|
Definition
| Four voltage sensitive gating particles. Three "m" gates, on "h" gate. All channels must be open to conduct a current. Depolarization opens "m" gates. |
|
|
Term
| True or False: Speed of propogation increases as Ra*Cm increases. |
|
Definition
| False.Speed of propogation increases as Ra*Cm decreases |
|
|
Term
| What reduces resistance in an axon but increases capacitance? |
|
Definition
| increasing the axons diameter |
|
|
Term
| T or F. Ra decreases in proportion to the diameter. |
|
Definition
| False. It decreases in proportion to the square of the diameter. |
|
|
Term
|
Definition
| Reduces Cm without changing Ra; wrapping myeling around the axon increases the thickness of the membrane making it a less effective capacitor. |
|
|
Term
|
Definition
|
|
Term
|
Definition
| breaks in myelin sheeths surrounding the axon |
|
|
Term
| Peripheral Nervous System |
|
Definition
| The sensory nerves and motor nerves that facilitate communication between the central nervous system and the body. |
|
|
Term
|
Definition
| Sensory neurons that carry info from the body to the CNS |
|
|
Term
|
Definition
| Motor neurons that carry info from the CNS to the periphery |
|
|
Term
|
Definition
| Subset of peripheral nervous system. Carries info related to the positiona nd the movement from the periphery and teh motor neurons that innervate the skeletal muscle. Controls voluntary movement and produces simple reflex arcs. |
|
|
Term
|
Definition
| In somatic nervous system. one long axon that releases Ach from the nerve terminal. the postsynaptic receptors are nAchRs |
|
|
Term
|
Definition
| the sensory afferents and motor efferents that are involved in regulating the function of the visceral organs. Regulates things like blood pressure, heart rate, temperature, perspiration, respiration etc.. Involuntary control |
|
|
Term
|
Definition
| In autonomic nervous system. |
|
|
Term
| Subdivisions of Autonomic Nervous System |
|
Definition
| Sympathetic, Parasympathetic, and Enteric |
|
|
Term
| Sympathetic Nervous System |
|
Definition
| Thoraculumbar subdivision |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Mostly thoracic, innervates the gut |
|
|
Term
|
Definition
| 31 Pairs. Forms the efferent pathway for alpha motorneurons and sympathetic fibers |
|
|
Term
| Similarities between the Parasympathetic Nervous system and the Sympathetic |
|
Definition
| frequently both innervate the same organs, each have a disynaptic pathway, have preganglionic neurons that release Ach, and postganglionic neurons that express nAchrs |
|
|
Term
|
Definition
| group of nerve cell bodies outside the CNS |
|
|
Term
| Sympathetic Chain ganglia |
|
Definition
| Close to CNS, house postganglionic neurons of the sympathetic nervous system |
|
|
Term
| True or False: Sympathetic output is generalized, while Parasympathetic output is localized. |
|
Definition
|
|
Term
|
Definition
| created from a balance of the sympathetic and parasympathetic systems |
|
|
Term
|
Definition
| An aa derived from tyrosine |
|
|
Term
|
Definition
| acts as a neurotransmitter and a hormone |
|
|
Term
|
Definition
| homoreceptor of norepinephrine; inhibits its own release |
|
|
Term
|
Definition
| produced in adrenal gland from methylation of NE, released from the adrenal medulla as a hormone |
|
|
