File: Chap011, Chapter 11: Functional Organization of Nervous Tissue
... Which of the following events is not a characteristic of an action potential? A) The plasma membrane becomes highly permeable to sodium ions and depolarization results. B) As sodium ions enter, the inside of the plasma membrane becomes more negative. C) At the peak of depolarization, sodium channels ...
... Which of the following events is not a characteristic of an action potential? A) The plasma membrane becomes highly permeable to sodium ions and depolarization results. B) As sodium ions enter, the inside of the plasma membrane becomes more negative. C) At the peak of depolarization, sodium channels ...
Chapter 11: Functional Organization of Nervous Tissue
... Which of the following events is not a characteristic of an action potential? A) The plasma membrane becomes highly permeable to sodium ions and depolarization results. B) As sodium ions enter, the inside of the plasma membrane becomes more negative. C) At the peak of depolarization, sodium channels ...
... Which of the following events is not a characteristic of an action potential? A) The plasma membrane becomes highly permeable to sodium ions and depolarization results. B) As sodium ions enter, the inside of the plasma membrane becomes more negative. C) At the peak of depolarization, sodium channels ...
Types of Model Neurons
... which displays membrane potential versus time. Currents and conductances are not displayed, as they have all been condensed into a single state variable, M, which is equivalent to the membrane potential. As the name implies, this model neuron sums all inputs it receives over time, and when the state ...
... which displays membrane potential versus time. Currents and conductances are not displayed, as they have all been condensed into a single state variable, M, which is equivalent to the membrane potential. As the name implies, this model neuron sums all inputs it receives over time, and when the state ...
Insights into structure of Golgi apparatus
... vesicles as models of the Golgi apparatus. By minimizing the energy of the stack at fixed total membrane area and volume, we allow the cisternae that form the apparatus to exchange their area and volume so as to adjust their individual shapes: This captures some features of the apparatus as a dynami ...
... vesicles as models of the Golgi apparatus. By minimizing the energy of the stack at fixed total membrane area and volume, we allow the cisternae that form the apparatus to exchange their area and volume so as to adjust their individual shapes: This captures some features of the apparatus as a dynami ...
neuromuscular transmission neuromuscular junction
... there is a marked proliferation of nicotinic receptors over a wide region of the neuromuscular junction. Denervation supersensitivity also occurs at autonomic junctions. Smooth muscle, unlike skeletal muscle, does not atrophy when denervated, but it becomes hyperresponsive to the chemical mediator t ...
... there is a marked proliferation of nicotinic receptors over a wide region of the neuromuscular junction. Denervation supersensitivity also occurs at autonomic junctions. Smooth muscle, unlike skeletal muscle, does not atrophy when denervated, but it becomes hyperresponsive to the chemical mediator t ...
Activity of Bipolar Potential Generation in Paramecium
... generation. Against input mechanical stimulation at the backward part, negative reception potential is induced at input port by efflux of K+ through mechanosensitive K+ channels (pulse), or chemical process for production of cyclic AMP as the second messenger mediated by some enzyme from ATP. When t ...
... generation. Against input mechanical stimulation at the backward part, negative reception potential is induced at input port by efflux of K+ through mechanosensitive K+ channels (pulse), or chemical process for production of cyclic AMP as the second messenger mediated by some enzyme from ATP. When t ...
The Nervous System
... Then label where Na+ moves into the axon (DEPOLARIZATION). Label the place where Na+ gates close and the K+ gates open. Then label where K+ moves out of the axon (REPOLARIZATION). Indicate the place where the [Na+] and [K+] are returned to their original concentrations. ...
... Then label where Na+ moves into the axon (DEPOLARIZATION). Label the place where Na+ gates close and the K+ gates open. Then label where K+ moves out of the axon (REPOLARIZATION). Indicate the place where the [Na+] and [K+] are returned to their original concentrations. ...
Fatigue
... a. The opening of voltage-gated K+ channels cause the membrane to _____________________. b. Does K+ move into or out of the cell? __________________ c. If the membrane potential becomes more negative than –70 mV, this is called _________. d. This potential is caused by what characteristic of K+ perm ...
... a. The opening of voltage-gated K+ channels cause the membrane to _____________________. b. Does K+ move into or out of the cell? __________________ c. If the membrane potential becomes more negative than –70 mV, this is called _________. d. This potential is caused by what characteristic of K+ perm ...
Neuromuscular Transmission - Dr. Logothetis
... The diversity of neurotransmitters is extensive, but their receptors can be grouped into two broad classes: ligand-gated ion channels and G protein-coupled receptors. By far the most-studied receptor is the muscle nicotinic acetylcholine receptor, the first ligand-gated ion channel to be purified, c ...
... The diversity of neurotransmitters is extensive, but their receptors can be grouped into two broad classes: ligand-gated ion channels and G protein-coupled receptors. By far the most-studied receptor is the muscle nicotinic acetylcholine receptor, the first ligand-gated ion channel to be purified, c ...
Chapter 7 - Faculty Web Sites
... There is a slight difference in charge across the membrane, which is called the resting potential The inner surface of the membrane is about 70 mV more negative than the outer surface There are more sodium ions outside the membrane than inside There are more potassium ions inside the membran ...
... There is a slight difference in charge across the membrane, which is called the resting potential The inner surface of the membrane is about 70 mV more negative than the outer surface There are more sodium ions outside the membrane than inside There are more potassium ions inside the membran ...
Neurotransmission
... Localization of neurotransmitter action. Neurotransmitters in general act either locally (A), by altering the electrical excitability of a small region of a single postsynaptic cell, or more diffusely (B), by altering the electrical excitability of a few postsynaptic cells. (C) Neurons can exert th ...
... Localization of neurotransmitter action. Neurotransmitters in general act either locally (A), by altering the electrical excitability of a small region of a single postsynaptic cell, or more diffusely (B), by altering the electrical excitability of a few postsynaptic cells. (C) Neurons can exert th ...
Membrane Domains and Membrane Potential
... membrane potential will return to the resting potential. If the neuron is at resting potential (-70mV) and the conductance to K+ increases, the membrane potential will be hyperpolarized (it will move toward -90mV). Transmission along the axon of a neuron occurs due to sequential activation of voltag ...
... membrane potential will return to the resting potential. If the neuron is at resting potential (-70mV) and the conductance to K+ increases, the membrane potential will be hyperpolarized (it will move toward -90mV). Transmission along the axon of a neuron occurs due to sequential activation of voltag ...
ANPS 019 Beneyto-Santonja 10-10
... Action potential arrives at synaptic terminal ACh is released into the synaptic cleft ACh binds to receptors on the post-synaptic membrane of the muscle cell o Action potential in sarcolemma Specific steps involved in the process of cholinergic transmission 1. Arrival of an action potential at ...
... Action potential arrives at synaptic terminal ACh is released into the synaptic cleft ACh binds to receptors on the post-synaptic membrane of the muscle cell o Action potential in sarcolemma Specific steps involved in the process of cholinergic transmission 1. Arrival of an action potential at ...
neuron is
... message that travels down the axon causing release of chemicals from axon terminal (neuron “fires”) • Ions: charged particles that move in and out of the axon ...
... message that travels down the axon causing release of chemicals from axon terminal (neuron “fires”) • Ions: charged particles that move in and out of the axon ...
Chapters 11: Introduction to the Nervous System and Nervous
... White matter – found in both brain and SC; (____________ axons) ____________ = bundles of white matter (processes in CNS) ____________ = clusters of cell bodies and dendrites (gray matter) ____________ matter – found in both brain and SC; (cell bodies, dendrites, and unmyelinated axons) ...
... White matter – found in both brain and SC; (____________ axons) ____________ = bundles of white matter (processes in CNS) ____________ = clusters of cell bodies and dendrites (gray matter) ____________ matter – found in both brain and SC; (cell bodies, dendrites, and unmyelinated axons) ...
Interactions of KCNE Auxiliary Subunits with K and other Channels
... It is interesting to note that while KCNE1 endows Kv7.1 with clear, slow voltage dependent activation10,11 (similar results were obtained with KCNE415 and KCNE516), the association of these pore-forming channels with KCNE217 and KCNE318, results in currents that lack voltage dependency and may serve ...
... It is interesting to note that while KCNE1 endows Kv7.1 with clear, slow voltage dependent activation10,11 (similar results were obtained with KCNE415 and KCNE516), the association of these pore-forming channels with KCNE217 and KCNE318, results in currents that lack voltage dependency and may serve ...
Neural Basis of Motor Control
... Remember, sodium has a positive charge, so the neuron becomes more positive and becomes depolarized. It takes longer for potassium channels to open. When they do open, potassium rushes out of the cell, reversing the depolarization. Also at about this time, sodium channels start to close. This causes ...
... Remember, sodium has a positive charge, so the neuron becomes more positive and becomes depolarized. It takes longer for potassium channels to open. When they do open, potassium rushes out of the cell, reversing the depolarization. Also at about this time, sodium channels start to close. This causes ...
File
... system. The concentration gradient of each of these ions across the membrane helps determine the voltage of the membrane potential. Second, the quantitative importance of each of the ions in determining the voltage is proportional to the membrane permeability for that particular ion. That is, if th ...
... system. The concentration gradient of each of these ions across the membrane helps determine the voltage of the membrane potential. Second, the quantitative importance of each of the ions in determining the voltage is proportional to the membrane permeability for that particular ion. That is, if th ...
Nervous System WS (handed out after section exam)
... c. What substance makes up the myelin sheath? ...
... c. What substance makes up the myelin sheath? ...
Solute transport - ASAB-NUST
... • Movement between phospholipid bilayer components • Bidirectional if gradient changes • Slow process ...
... • Movement between phospholipid bilayer components • Bidirectional if gradient changes • Slow process ...
The Membrane: Overview
... Integral proteins penetrate the hydrophobic core These proteins provide a wide variety of functions for the cell ...
... Integral proteins penetrate the hydrophobic core These proteins provide a wide variety of functions for the cell ...
5_Muscle
... At time 0, does the membrane begin to depolarize or repolarize? Unlike the graded potentials that get larger with increasing stimulus strength (e.g. at the motor end plate), the action potential is an all-or-none* response. Will a stronger stimulus produce a larger action potential? Explain. Give an ...
... At time 0, does the membrane begin to depolarize or repolarize? Unlike the graded potentials that get larger with increasing stimulus strength (e.g. at the motor end plate), the action potential is an all-or-none* response. Will a stronger stimulus produce a larger action potential? Explain. Give an ...
Slide 1
... outside the cell, and pull Potassium (K+) ions inside. • Potassium ions leak back out easily, but sodium ions are trapped outside. Several large, negatively charged molecules are trapped inside the cell. • This creates an electrical polarization, called the resting potential, with a relative posit ...
... outside the cell, and pull Potassium (K+) ions inside. • Potassium ions leak back out easily, but sodium ions are trapped outside. Several large, negatively charged molecules are trapped inside the cell. • This creates an electrical polarization, called the resting potential, with a relative posit ...
Action potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and endocrine cells, as well as in some plant cells. In neurons, they play a central role in cell-to-cell communication. In other types of cells, their main function is to activate intracellular processes. In muscle cells, for example, an action potential is the first step in the chain of events leading to contraction. In beta cells of the pancreas, they provoke release of insulin. Action potentials in neurons are also known as ""nerve impulses"" or ""spikes"", and the temporal sequence of action potentials generated by a neuron is called its ""spike train"". A neuron that emits an action potential is often said to ""fire"".Action potentials are generated by special types of voltage-gated ion channels embedded in a cell's plasma membrane. These channels are shut when the membrane potential is near the resting potential of the cell, but they rapidly begin to open if the membrane potential increases to a precisely defined threshold value. When the channels open (in response to depolarization in transmembrane voltage), they allow an inward flow of sodium ions, which changes the electrochemical gradient, which in turn produces a further rise in the membrane potential. This then causes more channels to open, producing a greater electric current across the cell membrane, and so on. The process proceeds explosively until all of the available ion channels are open, resulting in a large upswing in the membrane potential. The rapid influx of sodium ions causes the polarity of the plasma membrane to reverse, and the ion channels then rapidly inactivate. As the sodium channels close, sodium ions can no longer enter the neuron, and then they are actively transported back out of the plasma membrane. Potassium channels are then activated, and there is an outward current of potassium ions, returning the electrochemical gradient to the resting state. After an action potential has occurred, there is a transient negative shift, called the afterhyperpolarization or refractory period, due to additional potassium currents. This mechanism prevents an action potential from traveling back the way it just came.In animal cells, there are two primary types of action potentials. One type is generated by voltage-gated sodium channels, the other by voltage-gated calcium channels. Sodium-based action potentials usually last for under one millisecond, whereas calcium-based action potentials may last for 100 milliseconds or longer. In some types of neurons, slow calcium spikes provide the driving force for a long burst of rapidly emitted sodium spikes. In cardiac muscle cells, on the other hand, an initial fast sodium spike provides a ""primer"" to provoke the rapid onset of a calcium spike, which then produces muscle contraction.