Unit A: Nervous and Endocrine Systems
... • Neurons conduct an electrical impulse through the use of voltage differences • Nerve impulses are as strong at the end as at beginning ...
... • Neurons conduct an electrical impulse through the use of voltage differences • Nerve impulses are as strong at the end as at beginning ...
Describe how action potentials are generated
... Essay Question for exam 3 Describe how action potentials are generated and propagated along neurons. Include in your description how intracellular voltage changes during the action potential by labeling the action potential tracing (shown below) and describing what is occurring at that particular ti ...
... Essay Question for exam 3 Describe how action potentials are generated and propagated along neurons. Include in your description how intracellular voltage changes during the action potential by labeling the action potential tracing (shown below) and describing what is occurring at that particular ti ...
Describe how action potentials are generated and
... Essay Question for exam 3 Describe how action potentials are generated and propagated along neurons. Include in your description how intracellular voltage changes during the action potential by labeling the action potential tracing (shown below) and describing what is occurring at that particular ti ...
... Essay Question for exam 3 Describe how action potentials are generated and propagated along neurons. Include in your description how intracellular voltage changes during the action potential by labeling the action potential tracing (shown below) and describing what is occurring at that particular ti ...
Physiology Lecture Outline: Membrane Potential and Neurophysiology
... 2) The movement of K+ ions alone: If it is assumed that K+ ions are freely permeable, with no restrictions to its movement, then K+ ions will move back and forth across the membrane until the Electrochemical Gradient has Equilibrated. The value of the voltage across the membrane for the Equilibrium ...
... 2) The movement of K+ ions alone: If it is assumed that K+ ions are freely permeable, with no restrictions to its movement, then K+ ions will move back and forth across the membrane until the Electrochemical Gradient has Equilibrated. The value of the voltage across the membrane for the Equilibrium ...
Chapter 12 – Introduction to the Nervous System
... • Membrane potential creates a polarized membrane – Membrane as – pole & + pole ...
... • Membrane potential creates a polarized membrane – Membrane as – pole & + pole ...
Basis of Membrane Potential Action Potential Movie
... Generate Action Potentials • Action potential (AP) is a sudden and major change in membrane potential – Lasts 1-2 milliseconds – Pulse of electric charge is conducted along the axon at speeds up to 100 meters per second – Membrane potential changes from -60 to +50 mV ...
... Generate Action Potentials • Action potential (AP) is a sudden and major change in membrane potential – Lasts 1-2 milliseconds – Pulse of electric charge is conducted along the axon at speeds up to 100 meters per second – Membrane potential changes from -60 to +50 mV ...
1. Biophysics of the Nervous System
... particularly active methabolic Na-K pump, control internal and external concentrations. The action of this pump is in the opposite direction with passive leakage currents. Therefore, the concentrations of Na and K ions are kept at a certain level, by sending excessive ions back. The pump is electric ...
... particularly active methabolic Na-K pump, control internal and external concentrations. The action of this pump is in the opposite direction with passive leakage currents. Therefore, the concentrations of Na and K ions are kept at a certain level, by sending excessive ions back. The pump is electric ...
Nerve
... mEq/L -Na channels are inactive at rest, voltage gated, K the Oligodendrocytes: membrane potential Myelinating ...
... mEq/L -Na channels are inactive at rest, voltage gated, K the Oligodendrocytes: membrane potential Myelinating ...
Chapter 11 Marieb
... 2. So, the inward rush of Na+ slows to a stop 3. Around the same time, the voltage-gated K+ channels open 4. K+ moves down its gradient, leaving the cell 5. This is a rapid drop toward resting potential HYPERPOLARIZATION (more negative, moving away from resting potential) 1. Na+ channels reset to th ...
... 2. So, the inward rush of Na+ slows to a stop 3. Around the same time, the voltage-gated K+ channels open 4. K+ moves down its gradient, leaving the cell 5. This is a rapid drop toward resting potential HYPERPOLARIZATION (more negative, moving away from resting potential) 1. Na+ channels reset to th ...
Complete Nervous System Worksheet
... -nerve impulses reaching the presynaptic ending cause calcium ions to interact with contractile proteins. These proteins pull the synaptic vesicles (containing neurotransmitters) to the inner surface of the presynaptic cell membrane. -the synaptic vesicles merge with the presynaptic cell membrane (l ...
... -nerve impulses reaching the presynaptic ending cause calcium ions to interact with contractile proteins. These proteins pull the synaptic vesicles (containing neurotransmitters) to the inner surface of the presynaptic cell membrane. -the synaptic vesicles merge with the presynaptic cell membrane (l ...
Nervous System:
... Ion pumps in the cell membranes of neurons release three positively charged sodium ions, while taking in only two positively charged potassium ions which creates a negative charge inside the cell. The space inside the neuron now has a resting potential, which is a kind of membrane potential, because ...
... Ion pumps in the cell membranes of neurons release three positively charged sodium ions, while taking in only two positively charged potassium ions which creates a negative charge inside the cell. The space inside the neuron now has a resting potential, which is a kind of membrane potential, because ...
Nervous System Notes
... • Ions follow the laws of diffusion (movement from high to low concentrations) when moving thru membranes • Ions enter & leave the membrane thru channels or gates that are specific for that ion ...
... • Ions follow the laws of diffusion (movement from high to low concentrations) when moving thru membranes • Ions enter & leave the membrane thru channels or gates that are specific for that ion ...
Answers to End-of-Chapter Questions – Brooker et al ARIS site
... neuron - A highly specialized cell that communicates with another cell of its kind and with other types of cells by electrical or chemical signals. ...
... neuron - A highly specialized cell that communicates with another cell of its kind and with other types of cells by electrical or chemical signals. ...
nerve_pharmacy_(mana..
... Na+. K+ tends to leak out of the cell down its conc gradient, carrying +ve charge with it. (through K leak channels). • 2. non-diffusible anions (proteins, sulphate and phosphate ions) cannot leave the cell. • 3. very small amount of Na+ diffuses into the cell down its conc gradient. The mb only sli ...
... Na+. K+ tends to leak out of the cell down its conc gradient, carrying +ve charge with it. (through K leak channels). • 2. non-diffusible anions (proteins, sulphate and phosphate ions) cannot leave the cell. • 3. very small amount of Na+ diffuses into the cell down its conc gradient. The mb only sli ...
CNS II
... • Allows passage of specified types of ions • Two types (i) cation channels that most often allow sodium ions to pass, but allow potassium and/or calcium ions (ii) anion channels that allow mainly chloride ions • Cation channels: lines with negative charges. Attract positively charged sodium ions an ...
... • Allows passage of specified types of ions • Two types (i) cation channels that most often allow sodium ions to pass, but allow potassium and/or calcium ions (ii) anion channels that allow mainly chloride ions • Cation channels: lines with negative charges. Attract positively charged sodium ions an ...
Lectures 26-27 Study Guide
... a. Membrane potential: localized electrical gradient across the plasma membrane b. Resting potential: membrane potential of a resting neuron- one that is not sending signals. Two important things: i. The inside of the neuron is slightly negative compared to the outside. ii. Na+ has a high concentrat ...
... a. Membrane potential: localized electrical gradient across the plasma membrane b. Resting potential: membrane potential of a resting neuron- one that is not sending signals. Two important things: i. The inside of the neuron is slightly negative compared to the outside. ii. Na+ has a high concentrat ...
Resting Potential
... • The cell membrane of this neuron is polarized b/c of an un= distribution of ions on either side • Outside the neuron – • Inside the neuron – ...
... • The cell membrane of this neuron is polarized b/c of an un= distribution of ions on either side • Outside the neuron – • Inside the neuron – ...
PowerPoint version
... a. charges that pull sodium and potassium through the membrane b. opening of sodium and potassium channels in the membrane. c. the myelin sheath, which prevents ions from entering or leaving. d. transport and leakage of sodium and potassium into and out of the cell e. the mutual repulsion of sodium ...
... a. charges that pull sodium and potassium through the membrane b. opening of sodium and potassium channels in the membrane. c. the myelin sheath, which prevents ions from entering or leaving. d. transport and leakage of sodium and potassium into and out of the cell e. the mutual repulsion of sodium ...
Chapter 48 - cloudfront.net
... the postsynaptic membrane potential. If the neurotransmitters cause the K+ and Na+ ion channels to open and depolarization takes place then they’re called excitatory postsynaptic potentials(EPSPs) because the inside of the cell will be more positive which will bring the membrane potential closer tow ...
... the postsynaptic membrane potential. If the neurotransmitters cause the K+ and Na+ ion channels to open and depolarization takes place then they’re called excitatory postsynaptic potentials(EPSPs) because the inside of the cell will be more positive which will bring the membrane potential closer tow ...
The Neuron
... stored energy is released, get tremendous changes within cell During action potential: Na+ channels open – Remember: thousands of Na+ ions held on outside- now they rush in through these channels – Approximately 500x greater than normal number of Na+ ions – Small area inside membrane is depolarize ...
... stored energy is released, get tremendous changes within cell During action potential: Na+ channels open – Remember: thousands of Na+ ions held on outside- now they rush in through these channels – Approximately 500x greater than normal number of Na+ ions – Small area inside membrane is depolarize ...
Cellular Aspects - Labs - Department of Plant Biology, Cornell
... When the outside concentration of a positive ion is greater than the inside concentration, the ion will tend to diffuse into the cell using its thermal energy. If the membrane is already electrically hyperpolarized, the electrical potential inside the cell will become less negative and the membran ...
... When the outside concentration of a positive ion is greater than the inside concentration, the ion will tend to diffuse into the cell using its thermal energy. If the membrane is already electrically hyperpolarized, the electrical potential inside the cell will become less negative and the membran ...
Nervous System - Westminster College
... Why Does the Signal Travel? • Motion of electrical impulse along a neuron is called an action potential • For this to happen, there must be a difference in charge accumulation between inside and outside of cell (a.k.a. a voltage difference) ...
... Why Does the Signal Travel? • Motion of electrical impulse along a neuron is called an action potential • For this to happen, there must be a difference in charge accumulation between inside and outside of cell (a.k.a. a voltage difference) ...
Nervous System
... Open and close when the cells sense it is being stretch. This occurs when the cell becomes mechanically deformed. ...
... Open and close when the cells sense it is being stretch. This occurs when the cell becomes mechanically deformed. ...
Neurons and Nervous System
... refractory period during which they cannot open. Na+ channels have two gates: • An activation gate is closed at rest but opens quickly at threshold. • An inactivation gate is open at rest and closes at threshold but responds more slowly. The gate reopens 1–2 milliseconds later than the activation ...
... refractory period during which they cannot open. Na+ channels have two gates: • An activation gate is closed at rest but opens quickly at threshold. • An inactivation gate is open at rest and closes at threshold but responds more slowly. The gate reopens 1–2 milliseconds later than the activation ...
Resting potential
The relatively static membrane potential of quiescent cells is called the resting membrane potential (or resting voltage), as opposed to the specific dynamic electrochemical phenomena called action potential and graded membrane potential.Apart from the latter two, which occur in excitable cells (neurons, muscles, and some secretory cells in glands), membrane voltage in the majority of non-excitable cells can also undergo changes in response to environmental or intracellular stimuli. In principle, there is no difference between resting membrane potential and dynamic voltage changes like action potential from a biophysical point of view: all these phenomena are caused by specific changes in membrane permeabilities for potassium, sodium, calcium, and chloride ions, which in turn result from concerted changes in functional activity of various ion channels, ion transporters, and exchangers. Conventionally, resting membrane potential can be defined as a relatively stable, ground value of transmembrane voltage in animal and plant cells.Any voltage is a difference in electric potential between two points—for example, the separation of positive and negative electric charges on opposite sides of a resistive barrier. The typical resting membrane potential of a cell arises from the separation of potassium ions from intracellular, relatively immobile anions across the membrane of the cell. Because the membrane permeability for potassium is much higher than that for other ions (disregarding voltage-gated channels at this stage), and because of the strong chemical gradient for potassium, potassium ions flow from the cytosol into the extracellular space carrying out positive charge, until their movement is balanced by build-up of negative charge on the inner surface of the membrane. Again, because of the high relative permeability for potassium, the resulting membrane potential is almost always close to the potassium reversal potential. But in order for this process to occur, a concentration gradient of potassium ions must first be set up. This work is done by the ion pumps/transporters and/or exchangers and generally is powered by ATP.In the case of the resting membrane potential across an animal cell's plasma membrane, potassium (and sodium) gradients are established by the Na+/K+-ATPase (sodium-potassium pump) which transports 2 potassium ions inside and 3 sodium ions outside at the cost of 1 ATP molecule. In other cases, for example, a membrane potential may be established by acidification of the inside of a membranous compartment (such as the proton pump that generates membrane potential across synaptic vesicle membranes).