Action Potential Neurons at Work
... ions moving? The sodium channel begins to close and potassium is opened. Potassium out ...
... ions moving? The sodium channel begins to close and potassium is opened. Potassium out ...
The Nervous System
... Annelida: pair of brain-like cerebral ganglia and subpharyngeal ganglion Mollusca: ranges from simple nervous system to relatively complex systems that rival those of mammals ...
... Annelida: pair of brain-like cerebral ganglia and subpharyngeal ganglion Mollusca: ranges from simple nervous system to relatively complex systems that rival those of mammals ...
Chapter 13 and 16
... A. Astrocyte- function in creating bloodbrain barrier, provide structure B. Oligodendocyte- produce myelin sheath C. Microglia- immune cells of CNS, similar to macrophages D. Ependymal- found in ventricles of brain, produce cerebrospinal fluid ...
... A. Astrocyte- function in creating bloodbrain barrier, provide structure B. Oligodendocyte- produce myelin sheath C. Microglia- immune cells of CNS, similar to macrophages D. Ependymal- found in ventricles of brain, produce cerebrospinal fluid ...
Ch 48: Nervous System – part 1
... transmit signals from one location to another made up of: many axons are enclosed by an insulating layer called the include: 2) GLIAL CELLS (“GLIA”) - SUPPORTING CELLS 10 to 50 times more numerous than neurons provide structure; protect, insulate, assist neurons example: ...
... transmit signals from one location to another made up of: many axons are enclosed by an insulating layer called the include: 2) GLIAL CELLS (“GLIA”) - SUPPORTING CELLS 10 to 50 times more numerous than neurons provide structure; protect, insulate, assist neurons example: ...
Nerve cells - Dr Magrann
... 19. Which cells provide the myelin sheath for neurons in the CNS? 20. Which cells provide the myelin sheath for SCHWANN CELLS neurons in the PNS? 21. What is the function of MYELIN to speed up the rate of nerve impulse conduction. SHEATHS 22. What are the BARE regions of axonal NODES OF RANVIER memb ...
... 19. Which cells provide the myelin sheath for neurons in the CNS? 20. Which cells provide the myelin sheath for SCHWANN CELLS neurons in the PNS? 21. What is the function of MYELIN to speed up the rate of nerve impulse conduction. SHEATHS 22. What are the BARE regions of axonal NODES OF RANVIER memb ...
Nerve Notes
... A. Neurons - transmit nerve impulses B. Neuroglia carry out a variety of functions to aid and protect other components IV. ...
... A. Neurons - transmit nerve impulses B. Neuroglia carry out a variety of functions to aid and protect other components IV. ...
Name
... 13. ovoid glial cells that are phagocytic 14. not having the ability to reproduce 15. clusters of neuron cell bodies found in the PNS 16. a chemical which diffuses across the synapse in order to affect a postsynaptic neuron 17. stimulus strength NOT strong enough to cause a response 18. when these “ ...
... 13. ovoid glial cells that are phagocytic 14. not having the ability to reproduce 15. clusters of neuron cell bodies found in the PNS 16. a chemical which diffuses across the synapse in order to affect a postsynaptic neuron 17. stimulus strength NOT strong enough to cause a response 18. when these “ ...
How Neurons and Synapses Work
... becomes more negative then when at rest Sodium-potassium pump works to restore equilibrium Refractory Period – Cell is unable to accept another stimulus until it returns to rest ...
... becomes more negative then when at rest Sodium-potassium pump works to restore equilibrium Refractory Period – Cell is unable to accept another stimulus until it returns to rest ...
Structure of a Neuron
... Basis of the Resting Membrane Potential • Since Na+ ion are more concentrated in the ECF when a specific voltage gated Na+ channel opens Na+ will always rush into the cell by diffusion. • Since K+ ion channels are more concentrated in the ICF when a specific voltage gated K+ channel opens K+ will a ...
... Basis of the Resting Membrane Potential • Since Na+ ion are more concentrated in the ECF when a specific voltage gated Na+ channel opens Na+ will always rush into the cell by diffusion. • Since K+ ion channels are more concentrated in the ICF when a specific voltage gated K+ channel opens K+ will a ...
NS Outline
... iiii. Gray matter: concentration of cell bodies & unmyelinated fibers. (in PNS=ganglia; in CNS=nuclei). {Neurolemmacytes are most active during the first year of life, and spiral around an axon to leave a covering called the neurolemma. This covering will also aid in repair. Oligodendrocytes myelina ...
... iiii. Gray matter: concentration of cell bodies & unmyelinated fibers. (in PNS=ganglia; in CNS=nuclei). {Neurolemmacytes are most active during the first year of life, and spiral around an axon to leave a covering called the neurolemma. This covering will also aid in repair. Oligodendrocytes myelina ...
Nervous System
... hyperpolarization – inc in voltage across membrane (K+ out cell more negative) Some trigger depolarization (Na+ in cell less negative) Strong enough stimuli trigger action potential (nerve impulse) ...
... hyperpolarization – inc in voltage across membrane (K+ out cell more negative) Some trigger depolarization (Na+ in cell less negative) Strong enough stimuli trigger action potential (nerve impulse) ...
The Nervous System - chemistrywithmrsmorton
... to speed up nerve impulses Schwann cells: surround axons and form myelin sheath Myelin sheath: tight coil of wrapped membranes Nodes of Ranvier: gaps between Schwann cells ...
... to speed up nerve impulses Schwann cells: surround axons and form myelin sheath Myelin sheath: tight coil of wrapped membranes Nodes of Ranvier: gaps between Schwann cells ...
Nerve Cells and Nerve Impulses
... Figure 2.11 (a) Shapes of some glia cells. Oligodendrocytes produce myelin sheaths that insulate certain vertebrate axons in the central nervous system; Schwann cells have a similar function in the periphery. The oligodendrocyte is shown here forming a segment of myelin sheath for two axons; in fac ...
... Figure 2.11 (a) Shapes of some glia cells. Oligodendrocytes produce myelin sheaths that insulate certain vertebrate axons in the central nervous system; Schwann cells have a similar function in the periphery. The oligodendrocyte is shown here forming a segment of myelin sheath for two axons; in fac ...
Nervous Tissue
... Synapse • Specialized region of contact between two neurons • Nerve impulse is transmitted from one neuron to other through neurotransmitters • 3 varieties: axodendritic, axosomatic, axoaxonic • Parts: presynaptic part, synaptic cleft, postsynaptic part ...
... Synapse • Specialized region of contact between two neurons • Nerve impulse is transmitted from one neuron to other through neurotransmitters • 3 varieties: axodendritic, axosomatic, axoaxonic • Parts: presynaptic part, synaptic cleft, postsynaptic part ...
Chapter 12 - Marion ISD
... Sodium moves into cell Threshold potential point at which impulse is triggered All or none Gates stay open for a short time then close Movement to resting potential when potassium channels open (repolarization) Hyperpolarization precedes achieving resting potential again Refractory period-membrane r ...
... Sodium moves into cell Threshold potential point at which impulse is triggered All or none Gates stay open for a short time then close Movement to resting potential when potassium channels open (repolarization) Hyperpolarization precedes achieving resting potential again Refractory period-membrane r ...
11 Func[ons of the Nervous System Divisions of the Nervous System
... – Myelin sheath gaps between adjacent Schwann cells – Sites where axon collaterals can emerge ...
... – Myelin sheath gaps between adjacent Schwann cells – Sites where axon collaterals can emerge ...
Action Potentials & Nerve Conduction
... • A neuron may receive greater than 10, 000 inputs from presynaptic neurons. • The initiation of an action potential from several simultaneous subthreshold graded potentials, originating from different locations, is known as spatial summation. ...
... • A neuron may receive greater than 10, 000 inputs from presynaptic neurons. • The initiation of an action potential from several simultaneous subthreshold graded potentials, originating from different locations, is known as spatial summation. ...
File
... **White Matter + myelin ***Grey Matter – myelin Nodes of Ranvier • gaps between myelin sheath ...
... **White Matter + myelin ***Grey Matter – myelin Nodes of Ranvier • gaps between myelin sheath ...
Study/Review * Nervous System Part 2 * CNS and PNS
... the synaptic cleft are called ____________________________ 2. These cells make myelin on axons of the CNS: _______________________ 3. _________________________ are gaps in the myelin sheath 4. A change in ion/charge distribution across the axon membrane is called ___________________________ ...
... the synaptic cleft are called ____________________________ 2. These cells make myelin on axons of the CNS: _______________________ 3. _________________________ are gaps in the myelin sheath 4. A change in ion/charge distribution across the axon membrane is called ___________________________ ...
Nervous Tissue: Support Cells
... nerve cells; allows for the electrical signal to transmit faster (like wire coating) ...
... nerve cells; allows for the electrical signal to transmit faster (like wire coating) ...
Anatomy, composition and physiology of neuron, dendrite, axon,and
... action potentials are all or none every action potentials have same amplitude and duration information in the signal is represented by frequency and duration ...
... action potentials are all or none every action potentials have same amplitude and duration information in the signal is represented by frequency and duration ...
Biology 3201
... If an axon is stimulated above its threshold it will trigger an impulse down its length. The strength of the response is not dependent upon the stimulus. An axon cannot send a mild or strong response. It either responds or does not!!! ...
... If an axon is stimulated above its threshold it will trigger an impulse down its length. The strength of the response is not dependent upon the stimulus. An axon cannot send a mild or strong response. It either responds or does not!!! ...
Mind, Brain & Behavior
... positive ion makes the membrane potential more positive. When the membrane potential reaches threshold, voltage-gated Na+ ion channels open. After 1 msec, voltage-gated K+ channels open, polarizing the neuron again. Sodium-potassium pump helps restore neuron to its resting potential. ...
... positive ion makes the membrane potential more positive. When the membrane potential reaches threshold, voltage-gated Na+ ion channels open. After 1 msec, voltage-gated K+ channels open, polarizing the neuron again. Sodium-potassium pump helps restore neuron to its resting potential. ...
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.