M. Woodin
... Small patch of membrane is sealed to the tip of a micropipette The high resistance seal (called a gigaohm seal)ensures that currents flow through the amplifier rather than escaping through the rim of the patch ...
... Small patch of membrane is sealed to the tip of a micropipette The high resistance seal (called a gigaohm seal)ensures that currents flow through the amplifier rather than escaping through the rim of the patch ...
Nervous System and Neuron
... Nerve impulse is transmitted once the resting potential voltage is altered or "depolarized" - this is called an "action potential" - in response to a stimulus, membrane permeability is altered - voltage-sensitive protein channels in membrane open and admit Na+ ions in a small area - K+ ions flow ...
... Nerve impulse is transmitted once the resting potential voltage is altered or "depolarized" - this is called an "action potential" - in response to a stimulus, membrane permeability is altered - voltage-sensitive protein channels in membrane open and admit Na+ ions in a small area - K+ ions flow ...
Chapter 3 Notes (part 1) 1. Basic Elements of the Nervous System (a
... B. Cell Membrane/Cytoplasmic Membrane selectively-permeable membrane which separates the cytoplasm from the extracellular matrix contains ion channels and protein pumps which manage the flow of ions (charged particles) into and out of the cell C. Axon The part of the cell which carries the ele ...
... B. Cell Membrane/Cytoplasmic Membrane selectively-permeable membrane which separates the cytoplasm from the extracellular matrix contains ion channels and protein pumps which manage the flow of ions (charged particles) into and out of the cell C. Axon The part of the cell which carries the ele ...
Pg. 109 Action Potentials
... Find a classmate and ask them what their favorite book is and why. ...
... Find a classmate and ask them what their favorite book is and why. ...
Chapter 12 – Introduction to the Nervous System
... • During the peak of an AP, the polarity reverses – Negative outside, positive inside – Causes impulse to travel from site of AP to adjacent plasma membrane – No fluctuation in AP due to “all or nothing” principle – AP cannot travel backwards on axon due to refractory periods ...
... • During the peak of an AP, the polarity reverses – Negative outside, positive inside – Causes impulse to travel from site of AP to adjacent plasma membrane – No fluctuation in AP due to “all or nothing” principle – AP cannot travel backwards on axon due to refractory periods ...
Tayler
... Membrane potential – when a neuron is not stimulated Threshold – the critical level to which membrane potential must be depolarized in order to initiate an action potential Polarization of the neuron’s membrane: Sodium is on the outside and potassium is on the inside Resting potential gives ...
... Membrane potential – when a neuron is not stimulated Threshold – the critical level to which membrane potential must be depolarized in order to initiate an action potential Polarization of the neuron’s membrane: Sodium is on the outside and potassium is on the inside Resting potential gives ...
Functional Organization of Nervous Tissue Chapter 11
... outside cell- negative proteins in also, Na+ higher outside than inside – At equilibrium there is very little movement of K+ or other ions across plasma membrane ...
... outside cell- negative proteins in also, Na+ higher outside than inside – At equilibrium there is very little movement of K+ or other ions across plasma membrane ...
NEURONS, SENSE ORGANS, AND NERVOUS SYSTEMS
... • A key area for this integration is the axon hillock, where action potentials are most often generated. • Graded changes resulting from multiple signals reaching the dendrites, spread to the axon hillock, where all the depolarizations and hyperpolarizations sum. ...
... • A key area for this integration is the axon hillock, where action potentials are most often generated. • Graded changes resulting from multiple signals reaching the dendrites, spread to the axon hillock, where all the depolarizations and hyperpolarizations sum. ...
Notes – Neurons and the nervous system
... At rest, the fluid inside a neuron has an excess of negatively charged ions. i.e. a negative resting potential When a neuron is in its resting state, sodium channels are blocked, thus keeping excess positive ions out of the cell. When a nearby neuron fires an action potential, this triggers so ...
... At rest, the fluid inside a neuron has an excess of negatively charged ions. i.e. a negative resting potential When a neuron is in its resting state, sodium channels are blocked, thus keeping excess positive ions out of the cell. When a nearby neuron fires an action potential, this triggers so ...
The Nervous System
... • Stimulus causes Na+ gates to open. • Na+ influx changes membrane potential. • If Na+ influx is great enough to achieve threshold potential (-50mV), then all Na+ gates open. • “All or none” phenomenon…at threshold, all gates will be opened (below threshold, no extra gates will open) and stimulus is ...
... • Stimulus causes Na+ gates to open. • Na+ influx changes membrane potential. • If Na+ influx is great enough to achieve threshold potential (-50mV), then all Na+ gates open. • “All or none” phenomenon…at threshold, all gates will be opened (below threshold, no extra gates will open) and stimulus is ...
Nervous Sys Learning targets
... 1. List the basic functions of the nervous system 2. draw a concept map to show the structural and functional divisions of the nervous system 3. List the types of neuroglia and cite their functions ...
... 1. List the basic functions of the nervous system 2. draw a concept map to show the structural and functional divisions of the nervous system 3. List the types of neuroglia and cite their functions ...
Lecture 3 Review
... nervous system: acetylcholine, peptides, amino acids, and amines. You should know the types of neurotransmitters included in each of these groups as discussed in lecture. In addition to these four groups, more recently a group of chemicals signals called unconventional neurotransmitters have been de ...
... nervous system: acetylcholine, peptides, amino acids, and amines. You should know the types of neurotransmitters included in each of these groups as discussed in lecture. In addition to these four groups, more recently a group of chemicals signals called unconventional neurotransmitters have been de ...
Chapter 4
... Neurotransmitter – chemical stored in the synaptic vesicles that when released transmits messages to other neurons, muscles, or blood vessels Synaptic transmission occurs when neurotransmitter molecules pass across the synaptic cleft and depolarize or hyperpolarize the postsynaptic membrane. Hyperpo ...
... Neurotransmitter – chemical stored in the synaptic vesicles that when released transmits messages to other neurons, muscles, or blood vessels Synaptic transmission occurs when neurotransmitter molecules pass across the synaptic cleft and depolarize or hyperpolarize the postsynaptic membrane. Hyperpo ...
Types of neurons
... But new dendrites can grow Provides room for more connections to other neurons New connections are basis for learning ...
... But new dendrites can grow Provides room for more connections to other neurons New connections are basis for learning ...
The Nervous System - Zen Shiatsu Chicago
... o Neurons use changes in their membrane potential as communication signals for receiving, integrating and sending information. o A change in membrane potential can be caused by: Anything that alters ion concentrations on the two sides of the membrane Anything that changes membrane permeability t ...
... o Neurons use changes in their membrane potential as communication signals for receiving, integrating and sending information. o A change in membrane potential can be caused by: Anything that alters ion concentrations on the two sides of the membrane Anything that changes membrane permeability t ...
Types of neurons
... Inside of Cell Potassium (K+) can pass through to equalize its concentration ...
... Inside of Cell Potassium (K+) can pass through to equalize its concentration ...
Types of neurons
... Inside of Cell Potassium (K+) can pass through to equalize its concentration ...
... Inside of Cell Potassium (K+) can pass through to equalize its concentration ...
Bioenergetics - Eastern Michigan University
... • It uses ATP to actively pump Na+ out of the cell and K+ into the cell • It takes energy (ATP) to maintain the pump and the gradient ...
... • It uses ATP to actively pump Na+ out of the cell and K+ into the cell • It takes energy (ATP) to maintain the pump and the gradient ...
The Nervous System - biology-rocks
... K+ moves down its concentration gradient out of the axon Membrane potential reverts back to +40mV -65mV Since there is more negative ions inside compared to positive ions ...
... K+ moves down its concentration gradient out of the axon Membrane potential reverts back to +40mV -65mV Since there is more negative ions inside compared to positive ions ...
5 Action Potential.key
... ion channels (to discover their amino acid sequence) It was about 10 years after that (~2000) that the 3-dimensional structure and function of ion channels began to be understood ...
... ion channels (to discover their amino acid sequence) It was about 10 years after that (~2000) that the 3-dimensional structure and function of ion channels began to be understood ...
Nervous System
... Ions and Action Potential Cont. At resting potential, there are many more sodium ions on the outside, so the neuron is negatively charged relative to its external environment. The voltage difference at rest is -70mV. An action potential occurs when a neuron sends information down an axon, away from ...
... Ions and Action Potential Cont. At resting potential, there are many more sodium ions on the outside, so the neuron is negatively charged relative to its external environment. The voltage difference at rest is -70mV. An action potential occurs when a neuron sends information down an axon, away from ...
Chapter 12 – Introduction to the Nervous System
... • During the peak of an AP, the polarity reverses – Negative outside, positive inside – Causes impulse to travel from site of AP to adjacent plasma membrane – No fluctuation in AP due to “all or nothing” principle – AP cannot travel backwards on axon due to refractory periods ...
... • During the peak of an AP, the polarity reverses – Negative outside, positive inside – Causes impulse to travel from site of AP to adjacent plasma membrane – No fluctuation in AP due to “all or nothing” principle – AP cannot travel backwards on axon due to refractory periods ...
VII. The Nervous System
... 3. Chemical Synapse- a chemical called a neurotransmitter is released from the presynaptic cell and binds to receptors on a postsynaptic cells causing it to fire. a) An action potential arriving at the synaptic terminal at the end of an axon causes Ca+2 to rush through voltage sensitive channels b) ...
... 3. Chemical Synapse- a chemical called a neurotransmitter is released from the presynaptic cell and binds to receptors on a postsynaptic cells causing it to fire. a) An action potential arriving at the synaptic terminal at the end of an axon causes Ca+2 to rush through voltage sensitive channels b) ...
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.