Study/Review * Nervous System Part 2 * CNS and PNS
... 5. ___________________is a region between an axon terminal and a dendrite or cell body of another neuron 6. The name of an autoimmune demyelination disease characterized by antibodies to myelin is _________________________________ ...
... 5. ___________________is a region between an axon terminal and a dendrite or cell body of another neuron 6. The name of an autoimmune demyelination disease characterized by antibodies to myelin is _________________________________ ...
Ion Channels - Interactive Physiology
... neurotransmitter binding to each channel. • Ion channels typically have multiple binding sites for neurotransmitters and require the binding of more than one neurotransmitter molecule to open or close the channel. ...
... neurotransmitter binding to each channel. • Ion channels typically have multiple binding sites for neurotransmitters and require the binding of more than one neurotransmitter molecule to open or close the channel. ...
slides - Smith Lab
... 4. Ion Channels • Neuronal signaling is based on the movements of ions across cell membrane. • Hydrophilic pores through which ions flow from extracellular space to intracellular space or vice versa down their concentration gradients. • There are gated and non-gated ion channels in membrane. • Volt ...
... 4. Ion Channels • Neuronal signaling is based on the movements of ions across cell membrane. • Hydrophilic pores through which ions flow from extracellular space to intracellular space or vice versa down their concentration gradients. • There are gated and non-gated ion channels in membrane. • Volt ...
ANNB/Biology 261 Exam 1
... 1) What is the voltage clamp method and what does it tell you? Method in which the experimenter can “clamp” or hold the Vm constant and measure changes in membrane conductance/ currents at different voltages. This based on the relationship described by Ohm’s Law (Vm = Iion*Resistance or its variatio ...
... 1) What is the voltage clamp method and what does it tell you? Method in which the experimenter can “clamp” or hold the Vm constant and measure changes in membrane conductance/ currents at different voltages. This based on the relationship described by Ohm’s Law (Vm = Iion*Resistance or its variatio ...
Port Said International Schools Unit 1: Revision1
... for Potassium ions (K+) ( which diffuse from the inside to the outside of the membrane) than for Sodium ions (Na+) (which diffuse from outside to the inside of the membrane). This results in the accumulation of excess positive charges on the outer surface of the membrane. 2. Accumulation of high mol ...
... for Potassium ions (K+) ( which diffuse from the inside to the outside of the membrane) than for Sodium ions (Na+) (which diffuse from outside to the inside of the membrane). This results in the accumulation of excess positive charges on the outer surface of the membrane. 2. Accumulation of high mol ...
Action Potentials & Nerve Conduction
... Gated Channels Are Involved in Neuronal Signalling • In the nervous system, different channel types are responsible for transmitting electrical signals over long and short distances: •A) Graded potentials travel over short distances and are activated by the opening of mechanically or chemically gat ...
... Gated Channels Are Involved in Neuronal Signalling • In the nervous system, different channel types are responsible for transmitting electrical signals over long and short distances: •A) Graded potentials travel over short distances and are activated by the opening of mechanically or chemically gat ...
Lect3
... Unequal concentrations of ions • Initial diffusion of K+ down concentration gradient from I to II • This causes + charge to accumulate in II because + and - charges are separated – Remember that Cl- can’t cross the membrane ! • Therefore II becomes positive relative to I ...
... Unequal concentrations of ions • Initial diffusion of K+ down concentration gradient from I to II • This causes + charge to accumulate in II because + and - charges are separated – Remember that Cl- can’t cross the membrane ! • Therefore II becomes positive relative to I ...
Nervous System
... inside = +) = depolarization How? - controlled by gated protein channels in the membrane - stimulus small depolarization triggers opening of Na+ ion channels - if stimulus causes enough Na+ to move in = threshold: a stimulus causes minimum depolarization required to trigger an AP - increases permeab ...
... inside = +) = depolarization How? - controlled by gated protein channels in the membrane - stimulus small depolarization triggers opening of Na+ ion channels - if stimulus causes enough Na+ to move in = threshold: a stimulus causes minimum depolarization required to trigger an AP - increases permeab ...
The Neuron - VirtualAvenue
... charge that travels along an axon – a voltage spike occurs • This occurs when channels open up, briefly allowing positively charged sodium ions to rush in ...
... charge that travels along an axon – a voltage spike occurs • This occurs when channels open up, briefly allowing positively charged sodium ions to rush in ...
Structure and Physiology of Neurons
... – Dendrite (conducts electrical current towards cell body) – Cell body – Axon (conducts electrical current away from cell body) ...
... – Dendrite (conducts electrical current towards cell body) – Cell body – Axon (conducts electrical current away from cell body) ...
View Lymnea Poster - Wellesley College
... determined by calculating Tau/R. Input resistance can be determined over a range of membrane potentials by creating a V-I curve for both hyperpolarizing and depolarizing current pulses, and determining the slope. Notice in this example that input resistance decreases once threshold is reached (as in ...
... determined by calculating Tau/R. Input resistance can be determined over a range of membrane potentials by creating a V-I curve for both hyperpolarizing and depolarizing current pulses, and determining the slope. Notice in this example that input resistance decreases once threshold is reached (as in ...
Lecture 02
... Membrane is comprised of a double layer (bilayer) of lipids, i.e. molecules of fat. ...
... Membrane is comprised of a double layer (bilayer) of lipids, i.e. molecules of fat. ...
Biological Membranes Transport
... net movement of water into the cell; the cell becomes flaccid (limp), and the plant may wilt • In a hypertonic environment, plant cells lose water; eventually, the membrane pulls away from the wall, a usually lethal effect called plasmolysis ...
... net movement of water into the cell; the cell becomes flaccid (limp), and the plant may wilt • In a hypertonic environment, plant cells lose water; eventually, the membrane pulls away from the wall, a usually lethal effect called plasmolysis ...
Neurons, Synapses, the Nervous System
... The dendrites of olfactory receptor cells bind specific odor molecules present in the environment. The olfactory cells are located in the nasal cavity and have axons that connect to the olfactory bulb of the brain. Which of the following best describes the role of olfactory cells? a. they generate ...
... The dendrites of olfactory receptor cells bind specific odor molecules present in the environment. The olfactory cells are located in the nasal cavity and have axons that connect to the olfactory bulb of the brain. Which of the following best describes the role of olfactory cells? a. they generate ...
Can EVERY molecule pass through the cell membrane freely? Why
... Movement of Na+ and K+ ions across a membrane through the use of a pump. Requires Energy in the form of ATP & a Carrier Protein ...
... Movement of Na+ and K+ ions across a membrane through the use of a pump. Requires Energy in the form of ATP & a Carrier Protein ...
Membrane potential
Membrane potential (also transmembrane potential or membrane voltage) is the difference in electric potential between the interior and the exterior of a biological cell. With respect to the exterior of the cell, typical values of membrane potential range from –40 mV to –80 mV.All animal cells are surrounded by a membrane composed of a lipid bilayer with proteins embedded in it. The membrane serves as both an insulator and a diffusion barrier to the movement of ions. Ion transporter/pump proteins actively push ions across the membrane and establish concentration gradients across the membrane, and ion channels allow ions to move across the membrane down those concentration gradients. Ion pumps and ion channels are electrically equivalent to a set of batteries and resistors inserted in the membrane, and therefore create a voltage difference between the two sides of the membrane.Virtually all eukaryotic cells (including cells from animals, plants, and fungi) maintain a non-zero transmembrane potential, usually with a negative voltage in the cell interior as compared to the cell exterior ranging from –40 mV to –80 mV. The membrane potential has two basic functions. First, it allows a cell to function as a battery, providing power to operate a variety of ""molecular devices"" embedded in the membrane. Second, in electrically excitable cells such as neurons and muscle cells, it is used for transmitting signals between different parts of a cell. Signals are generated by opening or closing of ion channels at one point in the membrane, producing a local change in the membrane potential. This change in the electric field can be quickly affected by either adjacent or more distant ion channels in the membrane. Those ion channels can then open or close as a result of the potential change, reproducing the signal.In non-excitable cells, and in excitable cells in their baseline states, the membrane potential is held at a relatively stable value, called the resting potential. For neurons, typical values of the resting potential range from –70 to –80 millivolts; that is, the interior of a cell has a negative baseline voltage of a bit less than one-tenth of a volt. The opening and closing of ion channels can induce a departure from the resting potential. This is called a depolarization if the interior voltage becomes less negative (say from –70 mV to –60 mV), or a hyperpolarization if the interior voltage becomes more negative (say from –70 mV to –80 mV). In excitable cells, a sufficiently large depolarization can evoke an action potential, in which the membrane potential changes rapidly and significantly for a short time (on the order of 1 to 100 milliseconds), often reversing its polarity. Action potentials are generated by the activation of certain voltage-gated ion channels.In neurons, the factors that influence the membrane potential are diverse. They include numerous types of ion channels, some of which are chemically gated and some of which are voltage-gated. Because voltage-gated ion channels are controlled by the membrane potential, while the membrane potential itself is influenced by these same ion channels, feedback loops that allow for complex temporal dynamics arise, including oscillations and regenerative events such as action potentials.