What is the Nervous System?
... Glia have many functions Supply nourishment to cells Help remove neurons’ waste products Provide insulation around many axons ...
... Glia have many functions Supply nourishment to cells Help remove neurons’ waste products Provide insulation around many axons ...
7.012 Problem Set 6 FRIDAY November 19, 2004 Problem sets will
... e) Consider an experimental injection of a number of positive ions into the axonal cytoplasm of a neuron. Explain how the voltage-sensitive sodium (Na+) channels initiate an action potential in response to this injection. ...
... e) Consider an experimental injection of a number of positive ions into the axonal cytoplasm of a neuron. Explain how the voltage-sensitive sodium (Na+) channels initiate an action potential in response to this injection. ...
NeuralCell-Neurons.stud
... Structure of Neurons • Cell body (soma; perikaryon) • Axon : only one (branches are collaterals; terminals are end feet) • Dendrites : much shorter; one or more than ...
... Structure of Neurons • Cell body (soma; perikaryon) • Axon : only one (branches are collaterals; terminals are end feet) • Dendrites : much shorter; one or more than ...
Feb. 11
... – Principle of connectional specificity: neurons make specific connections at precise points of synaptic contact. ...
... – Principle of connectional specificity: neurons make specific connections at precise points of synaptic contact. ...
Lecture 8: Nervous System
... reach a -90mV membrane potential and enter the afterhyperpolarizing phase K+ channels close and the membrane potential returns to the resting potential of -70mV ...
... reach a -90mV membrane potential and enter the afterhyperpolarizing phase K+ channels close and the membrane potential returns to the resting potential of -70mV ...
Untitled 2
... - Axon can be very short or absent, but can also account for nearly the whole length of the neuron ...
... - Axon can be very short or absent, but can also account for nearly the whole length of the neuron ...
Nerve Cell Impulses
... membrane pores/gates: in Æ out pores • Na+ (sodium) ions have restricted access • Action potential increases permeability of Na+ • There is selectivity in opening/closing Na+ and K+ gates • Remember: Plasma membrane is semi-permeable to K+ – Physico-chemical ion selectivity channels – (i.e., K+ weak ...
... membrane pores/gates: in Æ out pores • Na+ (sodium) ions have restricted access • Action potential increases permeability of Na+ • There is selectivity in opening/closing Na+ and K+ gates • Remember: Plasma membrane is semi-permeable to K+ – Physico-chemical ion selectivity channels – (i.e., K+ weak ...
5 Nervous Tissue Lab 2011
... The sciatic nerve is a mixed nerve, containing sensory axons from neuron cell bodies in dorsal root ganglia and motor axons from neurons in spinal cord gray matter. Like all larger peripheral nerves bundles, it is also mixed in the sense of containing both somatic and autonomic nerve fibers. Scan th ...
... The sciatic nerve is a mixed nerve, containing sensory axons from neuron cell bodies in dorsal root ganglia and motor axons from neurons in spinal cord gray matter. Like all larger peripheral nerves bundles, it is also mixed in the sense of containing both somatic and autonomic nerve fibers. Scan th ...
Epilepsy & Membrane Potentials
... Schwann cells and Nodes of Ranvier Schwann cells make MYELIN MYELIN is an electrical insulator ...
... Schwann cells and Nodes of Ranvier Schwann cells make MYELIN MYELIN is an electrical insulator ...
Lec. 13new_04 - Prop. Action Potentials
... Saltatory Conduction 1) AP is conducted with little decrement and at great speed from node - node 2) AP can only be regenerated at node rather than point to point along the fiber 3) Because AP appears to "jump" from one node to the next -- called saltatory conduction ...
... Saltatory Conduction 1) AP is conducted with little decrement and at great speed from node - node 2) AP can only be regenerated at node rather than point to point along the fiber 3) Because AP appears to "jump" from one node to the next -- called saltatory conduction ...
Nervous System Lecture- Part II
... Prevent leakage of electrical current Increase the speed of impulse conduction Nodes of Ranvier – gaps along axon Thick axons are myelinated Thin axons are unmyelinated, conduct impulses more slowly ...
... Prevent leakage of electrical current Increase the speed of impulse conduction Nodes of Ranvier – gaps along axon Thick axons are myelinated Thin axons are unmyelinated, conduct impulses more slowly ...
1 Name: Period: _____ Laboratory Exercise and Activity: Nervous
... for proper nervous system development. There is not a continuous myelin sheath around the axon, and gaps do exist between the cells. Gaps in myelin sheaths are called nodes of Ranvier and are more numerous in the PNS than in the CNS. The myelin sheath provides protection and insulation for the axon, ...
... for proper nervous system development. There is not a continuous myelin sheath around the axon, and gaps do exist between the cells. Gaps in myelin sheaths are called nodes of Ranvier and are more numerous in the PNS than in the CNS. The myelin sheath provides protection and insulation for the axon, ...
Neural Pathways
... charge on the outside (excess Na+) and a negative charge on the inside 2. when stimulated, Na+ channels open temporarily becomes + and and Na+ rushes in -inside outside 3. channels then automatically close very quickly, but this causes the neighboring channels to open 4. it proceeds like a wave alon ...
... charge on the outside (excess Na+) and a negative charge on the inside 2. when stimulated, Na+ channels open temporarily becomes + and and Na+ rushes in -inside outside 3. channels then automatically close very quickly, but this causes the neighboring channels to open 4. it proceeds like a wave alon ...
electrochemical impulse - Glebe
... sensation (hypoesthesias and paraesthesias), muscle weakness, muscle spasms, or difficulty in moving;[15] difficulties with coordination and balance (ataxia);[15] problems in speech (dysarthria) or swallowing (dysphagia),[16] visual problems (nystagmus, optic neuritis, or diplopia),[17] fatigue, acu ...
... sensation (hypoesthesias and paraesthesias), muscle weakness, muscle spasms, or difficulty in moving;[15] difficulties with coordination and balance (ataxia);[15] problems in speech (dysarthria) or swallowing (dysphagia),[16] visual problems (nystagmus, optic neuritis, or diplopia),[17] fatigue, acu ...
sistem saraf (nervous system)
... The nerve impulses. • Italian scientist Luigi Galvani found that nerve tissue display electrical activity – nerve impulse – a flow of electrical charges along the cell membranes of a neuron. • Electrical activity is due to movement of ions ( potassium (K+) and Sodium (Na+) across the cell membra ...
... The nerve impulses. • Italian scientist Luigi Galvani found that nerve tissue display electrical activity – nerve impulse – a flow of electrical charges along the cell membranes of a neuron. • Electrical activity is due to movement of ions ( potassium (K+) and Sodium (Na+) across the cell membra ...
Neuroscience Course Conference
... b. What physiological or biochemical tests would you perform to determine the precise cause of the deficit in transmission? c. What general type of pharmacological agent might you try to generate symptomatic relief of this syndrome? Why? d. How would you expect the electromyogram (EMG) of such a per ...
... b. What physiological or biochemical tests would you perform to determine the precise cause of the deficit in transmission? c. What general type of pharmacological agent might you try to generate symptomatic relief of this syndrome? Why? d. How would you expect the electromyogram (EMG) of such a per ...
Nervous system power point notes #1
... • Peripheral nervous system (PNS) – The portion of the nervous system outside CNS – Consists mainly of nerves that extend from brain and spinal cord • Spinal nerves to and from spinal cord • Cranial nerves to and from brain © 2013 Pearson Education, Inc. ...
... • Peripheral nervous system (PNS) – The portion of the nervous system outside CNS – Consists mainly of nerves that extend from brain and spinal cord • Spinal nerves to and from spinal cord • Cranial nerves to and from brain © 2013 Pearson Education, Inc. ...
Nervous Tissue - NHSAdvancedBiology
... Other Parts of a Neuron • Myelin sheath - pearly white, shiny lipid substances that cover the axon of many neurons; protects, insulates, & allows for faster conduction of impulses • Neurilemma - delicate covering over myelin sheath (made by Schwann cells in PNS neurons); helps to repair damaged ner ...
... Other Parts of a Neuron • Myelin sheath - pearly white, shiny lipid substances that cover the axon of many neurons; protects, insulates, & allows for faster conduction of impulses • Neurilemma - delicate covering over myelin sheath (made by Schwann cells in PNS neurons); helps to repair damaged ner ...
L8_Nerve_tissue_and_organs
... • The neuron or nerve cell is the structural and functional unit of the nervous system • All neurons have a cell body (pericaryon) and processes, the axon and dendrites • Dendrites are neuronal processes that receive stimuli from other nerve cells or from the environment • Axons are neuronal process ...
... • The neuron or nerve cell is the structural and functional unit of the nervous system • All neurons have a cell body (pericaryon) and processes, the axon and dendrites • Dendrites are neuronal processes that receive stimuli from other nerve cells or from the environment • Axons are neuronal process ...
Nerve Cell Flashcards
... 28. What is Wallerian Degeneration? process that results when a nerve fiber is cut or crushed, in which the part of the axon separated from the neuron's cell body degenerates distal to the injury. ...
... 28. What is Wallerian Degeneration? process that results when a nerve fiber is cut or crushed, in which the part of the axon separated from the neuron's cell body degenerates distal to the injury. ...
Nerve Cell Flashcards
... 28. What is Wallerian Degeneration? process that results when a nerve fiber is cut or crushed, in which the part of the axon separated from the neuron's cell body degenerates distal to the injury. ...
... 28. What is Wallerian Degeneration? process that results when a nerve fiber is cut or crushed, in which the part of the axon separated from the neuron's cell body degenerates distal to the injury. ...
Neurotox I
... The choroid plexus separates the blood from the cerebrospinal fluid, whereas the blood-brain barrier limits the influx of circulating substances into the immediate brain interstitial space. Blood brain barrier limits influx of circulating substances from capillaries ...
... The choroid plexus separates the blood from the cerebrospinal fluid, whereas the blood-brain barrier limits the influx of circulating substances into the immediate brain interstitial space. Blood brain barrier limits influx of circulating substances from capillaries ...
Nerve Cell Physiology
... further depolarization and the opening of more fast Na+ channels. 2. Because Na+ conductance is high, the membrane potential rapidly approaches the equilibrium potential for Na+ (- +70 m V). 3. As membrane potential becomes positive, fast Na+ channels begin to inactivate, resulting in a rapid reduct ...
... further depolarization and the opening of more fast Na+ channels. 2. Because Na+ conductance is high, the membrane potential rapidly approaches the equilibrium potential for Na+ (- +70 m V). 3. As membrane potential becomes positive, fast Na+ channels begin to inactivate, resulting in a rapid reduct ...
Node of Ranvier
The nodes of Ranvier also known as myelin sheath gaps, are the gaps (approximately 1 micrometer in length) formed between the myelin sheaths generated by different cells. A myelin sheath is a many-layered coating, largely composed of a fatty substance called myelin, that wraps around the axon of a neuron and very efficiently insulates it. At nodes of Ranvier, the axonal membrane is uninsulated and, therefore, capable of generating electrical activity.