Nervous System Student Notes File
... neurotransmitters that open Na+ gates triggering depolarization c) _________________________________________________ (IPSP) are caused by neurotransmitters which open K+ or Cl- gates causing hyperpolarization d) A single EPSP is rarely strong enough to trigger an action potential, although and addit ...
... neurotransmitters that open Na+ gates triggering depolarization c) _________________________________________________ (IPSP) are caused by neurotransmitters which open K+ or Cl- gates causing hyperpolarization d) A single EPSP is rarely strong enough to trigger an action potential, although and addit ...
1 Neurons 2 Electrical activity of neurons at rest.
... capacitance C) producing the capacitive current C dV dt Ions can move into and out of the cell through ionic channels - special protein complexes, spanning the cellular membrane that allow through only particular kinds of ions. There are several different types of channels for each of the common ion ...
... capacitance C) producing the capacitive current C dV dt Ions can move into and out of the cell through ionic channels - special protein complexes, spanning the cellular membrane that allow through only particular kinds of ions. There are several different types of channels for each of the common ion ...
Nervous tissue
... • depolarization decreases potential across cell membrane due to opening of gated Na+ channels • Na+ rushes in down concentration and electrical gradients • Na+ diffuses for short distance inside membrane producing a change in voltage called a local potential ...
... • depolarization decreases potential across cell membrane due to opening of gated Na+ channels • Na+ rushes in down concentration and electrical gradients • Na+ diffuses for short distance inside membrane producing a change in voltage called a local potential ...
electrochemical impulse - Glebe
... o E.g. warm water = low frequency, hot water = high frequency 2. Different neurons have different thresholds o E.g. water at 40°C will cause one neuron to reach threshold level, but water at 60°C may cause two or more o Brain distinguishes between neural impulses Synaptic Transmission Neurons can ...
... o E.g. warm water = low frequency, hot water = high frequency 2. Different neurons have different thresholds o E.g. water at 40°C will cause one neuron to reach threshold level, but water at 60°C may cause two or more o Brain distinguishes between neural impulses Synaptic Transmission Neurons can ...
PPTX - Bonham Chemistry
... its target cell. The distinction between a neurotransmitter and a hormone is physiological, not chemical. It depends on whether the molecule acts over a short distance (across a synapse) or over a long distance (from the secretory organ, through the blood, to its site of action). ...
... its target cell. The distinction between a neurotransmitter and a hormone is physiological, not chemical. It depends on whether the molecule acts over a short distance (across a synapse) or over a long distance (from the secretory organ, through the blood, to its site of action). ...
Physio Lab 5 PhysioEx 3
... All cells have a resting membrane potential (RMP). Intracellular fluid is rich in negatively charged proteins that are balanced mainly by positively charge potassium ions. As the cell membrane is permeable or “leaky” to potassium but not to protein, the excess unbalanced negative charge leads to the ...
... All cells have a resting membrane potential (RMP). Intracellular fluid is rich in negatively charged proteins that are balanced mainly by positively charge potassium ions. As the cell membrane is permeable or “leaky” to potassium but not to protein, the excess unbalanced negative charge leads to the ...
Peripheral nervous system
... ◦ Form myelin sheaths around nerve fibers ◦ MS (multiple sclerosis) attacks myelin sheaths, converts them to hard covers that can’t conduct electrical impulses slurred speech, loss of balance, impaired vision, etc ...
... ◦ Form myelin sheaths around nerve fibers ◦ MS (multiple sclerosis) attacks myelin sheaths, converts them to hard covers that can’t conduct electrical impulses slurred speech, loss of balance, impaired vision, etc ...
overview of neural f..
... The sodium-potassium pump is an active process that returns & maintains levels of Na+ and K+ ...
... The sodium-potassium pump is an active process that returns & maintains levels of Na+ and K+ ...
Packet 6- The neuron
... 3. 1 millisecond later, the INACTIVATION GATE snaps shut. This is triggered by the same voltage stimulus that opened the gate…but this part of the change happens a fraction of a second SLOWER. A. The INACTIVATION GATE will NOT reopen until the membrane potential returns to resting levels, at which ...
... 3. 1 millisecond later, the INACTIVATION GATE snaps shut. This is triggered by the same voltage stimulus that opened the gate…but this part of the change happens a fraction of a second SLOWER. A. The INACTIVATION GATE will NOT reopen until the membrane potential returns to resting levels, at which ...
Central Nervous System
... Myelinated neurons faster than unmyelinated Myelinated fibers conduct impulses from one Node of Ranvier to the next, a phenomenon called saltatory conduction. Speed of impulse conduction is proportional to the diameter of the axon a.Thick, myelinated motor axons conduct at 120 m/s b.Thin, unmyeli ...
... Myelinated neurons faster than unmyelinated Myelinated fibers conduct impulses from one Node of Ranvier to the next, a phenomenon called saltatory conduction. Speed of impulse conduction is proportional to the diameter of the axon a.Thick, myelinated motor axons conduct at 120 m/s b.Thin, unmyeli ...
Chapter 10
... can help explain the actions of certain drugs • drugs have different mechanisms of action • several questions remain about the biological effects of addiction, such as why some individuals become ...
... can help explain the actions of certain drugs • drugs have different mechanisms of action • several questions remain about the biological effects of addiction, such as why some individuals become ...
What is a membrane potential?
... Costs of membrane potential with respect to ATP use and production. What organelles “could” facilitate this and why are neurons so sensitive to hypoxia? Neurons maintain a “FINE” balance between ATP Supply and Use, why is this so? • Perfusion of the brain • Na+/K+-ATPase function at rest and when c ...
... Costs of membrane potential with respect to ATP use and production. What organelles “could” facilitate this and why are neurons so sensitive to hypoxia? Neurons maintain a “FINE” balance between ATP Supply and Use, why is this so? • Perfusion of the brain • Na+/K+-ATPase function at rest and when c ...
Physio study guide unit 2
... Fact: the body fluid compartments have the same concentration. What is this magical number? Fact: the body fluid compartments have different compositions: why don’t these solutes simply diffuse? ...
... Fact: the body fluid compartments have the same concentration. What is this magical number? Fact: the body fluid compartments have different compositions: why don’t these solutes simply diffuse? ...
Neuroscience Course Conference
... in skeletal muscle has been shown to cause the mutant channels to have defective inactivation gates. In a heterozygote, approximately half of the channels are normal and the other half are in the mutant form. The mutant channels are normal, except that at any given time about 6% of them will not ina ...
... in skeletal muscle has been shown to cause the mutant channels to have defective inactivation gates. In a heterozygote, approximately half of the channels are normal and the other half are in the mutant form. The mutant channels are normal, except that at any given time about 6% of them will not ina ...
Ch11AB
... What is the average voltage an Action Potential generates on the inside of the axon membrane? Is it positive or negative? ...
... What is the average voltage an Action Potential generates on the inside of the axon membrane? Is it positive or negative? ...
Biology 3201
... Responsible for transferring impulses from receptors to CNS and back to effectors. ...
... Responsible for transferring impulses from receptors to CNS and back to effectors. ...
Na+ - cloudfront.net
... Dendrite receives neurotransmitter signal Cell body relays signal to axon Na+ channels open and Na+ rushes inside K+ channels open to let K+ out Causes other Na+ channels to open, like a chain reaction 6. Action potential reaches synaptic terminals 7. Neurotransmitter is released and goes to dendrit ...
... Dendrite receives neurotransmitter signal Cell body relays signal to axon Na+ channels open and Na+ rushes inside K+ channels open to let K+ out Causes other Na+ channels to open, like a chain reaction 6. Action potential reaches synaptic terminals 7. Neurotransmitter is released and goes to dendrit ...
The Nervous System
... • Why does Na+ diffuse in from the outside? – Higher concentration on the outside ...
... • Why does Na+ diffuse in from the outside? – Higher concentration on the outside ...
Single Unit Recording
... electrode introduced into the brain of a living animal will detect electrical activity that is generated by the neurons adjacent to the electrode tip. If the electrode is a microelectrode, with a tip size of 3 to 10 micrometers, the electrode will often isolate the activity of a single neuron. The a ...
... electrode introduced into the brain of a living animal will detect electrical activity that is generated by the neurons adjacent to the electrode tip. If the electrode is a microelectrode, with a tip size of 3 to 10 micrometers, the electrode will often isolate the activity of a single neuron. The a ...
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.