Neuroscience Principles Quiz

Action potential = Change in electrical potential associated with the passage of an impulse along the membrane of a muscle cell or nerve cell Cytosol = The liquid within a cell that contains the organelles Anions = Atoms or molecules with a net negative charge Hydrophilic compounds = Compounds that dissolve in water due to uneven electrical charge

Spheres of hydration = When water molecules surround a dissolved ion Cations = Atoms or molecules with a net positive charge Resting membrane potential = The electrical potential of a neuron or other excitable cell relative to its surroundings when it is not being stimulated or involved in passage of an impulse Hydrophobic compounds = Compounds that do not dissolve in water due to even electrical charge

Extracellular fluid = Body fluid outside the cells Water = Key ingredient in intracellular and extracellular fluid Ions = Atoms or molecules with a net electrical charge Phospholipid membrane = Bi-layer that forms the boundary of cells

<p>Lipids = Hydrophobic compounds Sodium chloride = Common salt, example of a compound that dissolves in water Simple reflex = An automatic and rapid response to a stimulus, that involves a message sent to the central nervous system and a response sent back Neuroscience = Scientific study of the nervous system</p> Signup and view all the answers

<p>Polar solvent = A solvent with a net dipole moment, such as water Intracellular fluid = Fluid within cells Neuroscience principles = Basic concepts and theories explaining the functioning of the nervous system Chemical cast = The set of chemicals involved in a particular process</p> Signup and view all the answers

<p>Selective permeability = Characteristic of potassium channels, key determinant of resting membrane potential Shaker potassium channel = Example of a K+ channel MacKinnon = 2003 Nobel Prize winner related to specific K+ channels Blood-brain barrier = Mechanism regulating the external potassium concentration</p> Signup and view all the answers

<p>Lily &amp; Yuh-Nung Jan = Research on amino acid sequences, family of K+ channels MacKinnon = Research related to mutations of specific K+ channels and inherited neurological disorders Wolters Kluwer = Publisher of the copyright for the given text</p> Signup and view all the answers

<p>Resting Membrane Potential = Condition where the membrane potential is close to EK because it is mostly permeable to K+ Potassium Channel Pore = Structure through which K+ ions pass Potassium spatial buffering by astrocytes = Mechanism regulating the external potassium concentration Sodium-potassium pump = Maintains large K+ concentration gradient</p> Signup and view all the answers

<p>Increased extracellular K+ = Condition that depolarizes membrane. Potassium channels = Contribute to resting potential Ion pumps = Play a role in the electrical potential difference across the membrane Battery = Analogous to the electrical potential difference across the membrane</p> Signup and view all the answers

<p>K+ channels = Four subunits Resting membrane potential = Sensitive to extracellular K+ Mutations of specific K+ channels = Associated with inherited neurological disorders Regulation of external K+ concentration = Importance in the ionic basis of the resting membrane potential</p> Signup and view all the answers

<p>Selective permeability = Characteristic that allows K+ ions to pass through channels Membrane potential = Sensitive to extracellular K+, similar to a battery Resting membrane potential = Close to EK due to permeability to K+ Increased extracellular K+ = Leads to membrane depolarization</p> Signup and view all the answers

<p>Ionic basis of the resting membrane potential = Relates to relative ion permeabilities of the membrane at rest Potassium channels = Selectively permeable to K+ ions Sodium-potassium pump = Activity maintains large K+ concentration gradient Potassium spatial buffering by astrocytes = Regulates external potassium concentration</p> Signup and view all the answers

<p>MacKinnon = 2003 Nobel Prize winner for work on K+ channels Shaker potassium channel = A type of K+ channel Selective permeability = Key determinant of resting membrane potential Resting membrane potential = State when membrane is mostly permeable to K+</p> Signup and view all the answers

<p>Selective permeability = Allows passage of K+ ions through channels Shaker potassium channel = A specific type of K+ channel Resting membrane potential = Close to EK due to permeability to K+ Increased extracellular K+ = Depolarizes the membrane</p> Signup and view all the answers

<p>Potassium channels = Selectively permeable to K+ ions Resting membrane potential = Sensitive to extracellular K+ Sodium-potassium pump = Maintains large K+ concentration gradient Potassium spatial buffering by astrocytes = Regulates external potassium concentration</p> Signup and view all the answers

<p>Phospholipid bilayer = Special proteins that span this structure control resting and action potentials Protein structure = Composed of four levels: Primary, Secondary, Tertiary, Quaternary Ion pumps = Formed by membrane-spanning proteins and use energy from ATP breakdown for neuronal signaling Equilibrium potential (Eion) = No net movement of ions when separated by a phospholipid membrane</p> Signup and view all the answers

<p>Diffusion = Process where dissolved ions distribute evenly and flow down concentration gradient when channels are permeable to specific ions and concentration gradient exists across the membrane Electrical conductance (g) and resistance (R) = Where $R = 1/g$ Ohm’s law = Expressed as $I = gV$ where I is the current, g is the conductance and V is the voltage Membrane potential = Voltage across the neuronal membrane at any moment</p> Signup and view all the answers

<p>Nernst equation = Calculates the exact value of the equilibrium potential for each ion in mV The sodium-potassium pump = An enzyme that breaks down ATP when Na present Goldman equation = Takes into account permeability of membrane to different ions Calcium pump = Actively transports Ca2+ out of cytosol</p> Signup and view all the answers

<p>K+ = More concentrated on the inside of the membrane Na+ = More concentrated on the outside of the membrane Ca2+ = More concentrated on the outside of the membrane</p> Signup and view all the answers

<p>Channel proteins = Have polar R groups and nonpolar R groups, contribute to ion selectivity and gating Proteins = Molecules assembled from amino acids, composing enzymes, cytoskeletal elements, receptors Equilibrium potential = The electrical potential difference that exactly balances the ionic concentration gradient Rate of movement of ions across membrane = Proportional to $Vm – Eion$</p> Signup and view all the answers

<p>Resting membrane potential = Relative ion permeabilities of the membrane at rest determine this Equilibrium potential = Inside is positively charged relative to outside Membrane ion channel = Formed by channel proteins with polar and nonpolar R groups Electrical current flow across a membrane = Governed by Ohm’s law</p> Signup and view all the answers

<p>Electrical potential (voltage) = Influences ion movement Neuronal signaling = Ion pumps use energy from ATP breakdown for this Ions = Flow down concentration gradient when channels are permeable to specific ions and concentration gradient exists across the membrane Ionic concentration gradient = Balanced by the electrical potential difference in the equilibrium potential</p> Signup and view all the answers

<p>The sodium-potassium pump = Breaks down ATP when Na present Calcium pump = Actively transports Ca2+ out of cytosol Equilibrium potential = No net movement of ions when separated by a phospholipid membrane Protein structure = Composed of amino acids, alpha carbon, and R groups</p> Signup and view all the answers

<p>Phospholipid bilayer = Special proteins that span this structure control resting and action potentials Membrane potential = Voltage across the neuronal membrane at any moment Equilibrium potential = Large changes in Vm from minuscule changes in ionic concentrations The Nernst equation = Calculates the exact value of the equilibrium potential for each ion in mV</p> Signup and view all the answers

<p>Electrical conductance (g) and resistance (R) = Where $R = 1/g$ Ohm’s law = Expressed as $I = gV$ The distribution of ions across the membrane = K+ more concentrated on inside, Na+ and Ca2+ more concentrated outside The sodium-potassium pump = An enzyme that breaks down ATP when Na present</p> Signup and view all the answers

<p>Water is a polar solvent.</p> Signup and view all the answers

<p>Atoms or molecules with a net electrical charge.</p> Signup and view all the answers

<p>Positive.</p> Signup and view all the answers

<p>Negative.</p> Signup and view all the answers

<p>Ions.</p> Signup and view all the answers

<p>Spheres of hydration.</p> Signup and view all the answers

<p>Hydrophilic compounds.</p> Signup and view all the answers

<p>Hydrophobic compounds.</p> Signup and view all the answers

<p>They are hydrophobic.</p> Signup and view all the answers

<p>Phospholipid membrane.</p> Signup and view all the answers

<p>Selective permeability of potassium channels</p> Signup and view all the answers

<p>four</p> Signup and view all the answers

<p>K+</p> Signup and view all the answers

<p>Membrane depolarization</p> Signup and view all the answers

<p>Blood-brain barrier and potassium spatial buffering by astrocytes</p> Signup and view all the answers

<p>Activity of the sodium-potassium pump</p> Signup and view all the answers

<p>A battery</p> Signup and view all the answers

<p>Resting potential</p> Signup and view all the answers

<p>To maintain ion concentration gradients</p> Signup and view all the answers

<p>Shaker potassium channel</p> Signup and view all the answers

<p>Proteins control resting and action potentials.</p> Signup and view all the answers

<p>Primary, secondary, tertiary, and quaternary.</p> Signup and view all the answers

<p>Resistance (R) is the inverse of conductance (g), and electrical current (I) is equal to conductance multiplied by voltage (V).</p> Signup and view all the answers

<p>The equilibrium potential is the electrical potential difference that exactly balances the ionic concentration gradient, resulting in no net movement of ions across the membrane.</p> Signup and view all the answers

<p>The Nernst equation calculates the exact value of the equilibrium potential for each ion, taking into consideration the charge of the ion, temperature, and ratio of external and internal ion concentrations.</p> Signup and view all the answers

<p>The sodium-potassium pump actively transports sodium (Na+) out of the cell and potassium (K+) into the cell, using ATP as energy.</p> Signup and view all the answers

<p>The Goldman equation takes into account the permeability of the membrane to different ions, determining the relative ion permeabilities and thus the membrane potential.</p> Signup and view all the answers

<p>Potassium (K+) is more concentrated on the inside of the membrane, while sodium (Na+) and calcium (Ca2+) are more concentrated on the outside.</p> Signup and view all the answers

<p>Diffusion allows dissolved ions to distribute evenly and ions flow down a concentration gradient when channels are permeable to specific ions and a concentration gradient exists across the membrane.</p> Signup and view all the answers

<p>Electrical current influences ion movement, with electrical conductance (g) and resistance (R) determining the flow of ions. Ohm's law states that current (I) is equal to conductance (g) multiplied by voltage (V).</p> Signup and view all the answers