Chapter Outline
... e. The pump is always working because the membrane is permeable to these ions and they tend to diffuse toward the lesser concentration. f. Since the plasma membrane is more permeable to potassium ions than to sodium ions, there are always more positive ions outside; this accounts for some polarity. ...
... e. The pump is always working because the membrane is permeable to these ions and they tend to diffuse toward the lesser concentration. f. Since the plasma membrane is more permeable to potassium ions than to sodium ions, there are always more positive ions outside; this accounts for some polarity. ...
Nervous System
... thoracic and lumbar segments of the spinal cord. Cells of origin for the parasympathetic nerves are located in the brain and sacral segments of the spinal cord. For both sympathetic and parasympathetic activity, two neurons are utilized for transmission from the cells of ...
... thoracic and lumbar segments of the spinal cord. Cells of origin for the parasympathetic nerves are located in the brain and sacral segments of the spinal cord. For both sympathetic and parasympathetic activity, two neurons are utilized for transmission from the cells of ...
Chapter 9 - Nervous System
... B. The brain can be divided into the cerebrum (largest portion and associated with higher mental functions), the diencephalon (processes sensory input), the cerebellum (coordinates muscular activity), and the brain stem (coordinates and regulates visceral activities). C. Structure of the Cerebrum (F ...
... B. The brain can be divided into the cerebrum (largest portion and associated with higher mental functions), the diencephalon (processes sensory input), the cerebellum (coordinates muscular activity), and the brain stem (coordinates and regulates visceral activities). C. Structure of the Cerebrum (F ...
Therapeutic Restoration of Spinal Inhibition via
... concentration ([Cl−]i). When GABAAR channels are opened, the Vm is pulled toward the Cl− equilibrium potential (ECl), which is determined by [Cl−]i and the extracellular Cl− concentration ([Cl−]e), the latter of which remains relatively constant. The potassium [K+]–Cl− cotransporter KCC2 is the majo ...
... concentration ([Cl−]i). When GABAAR channels are opened, the Vm is pulled toward the Cl− equilibrium potential (ECl), which is determined by [Cl−]i and the extracellular Cl− concentration ([Cl−]e), the latter of which remains relatively constant. The potassium [K+]–Cl− cotransporter KCC2 is the majo ...
The Origins of Two-State Spontaneous Membrane Potential
... showed that the cell-to-cell variation in membrane potential observed in these experiments was not attributable entirely to uncompensated tip potentials. For example, the difference between the Up and Down states was no less variable than either alone, ...
... showed that the cell-to-cell variation in membrane potential observed in these experiments was not attributable entirely to uncompensated tip potentials. For example, the difference between the Up and Down states was no less variable than either alone, ...
9d. Know the functions of the nervous system and the role of
... organs to the central nervous system and back to muscles or glands. When you step on a tack, sensory receptors stimulate a sensory neuron, which relays the signal to an interneuron within the spinal cord. The signal is then sent to a motor neuron, which in turn stimulates a muscle in your leg to ...
... organs to the central nervous system and back to muscles or glands. When you step on a tack, sensory receptors stimulate a sensory neuron, which relays the signal to an interneuron within the spinal cord. The signal is then sent to a motor neuron, which in turn stimulates a muscle in your leg to ...
Cardiac Qs
... The resting membrane potential of the cells of the SA node is between -55 to -60 mV which is less than normal. The lower negativity is caused by the leaky nature of the membrane of there cells which allow sodium and calcium ions to enter and thus reduce the negativity of the cell interior. Although ...
... The resting membrane potential of the cells of the SA node is between -55 to -60 mV which is less than normal. The lower negativity is caused by the leaky nature of the membrane of there cells which allow sodium and calcium ions to enter and thus reduce the negativity of the cell interior. Although ...
Voltage-Gated Ion Channels and the Propagation of Action
... to opening of voltage-gated K channels. The subsequent increased efflux of K from the cytosol removes the excess positive charges from the cytosolic face of the plasma membrane (i.e., makes it more negative), thereby restoring the inside-negative resting potential. Actually, for a brief instant th ...
... to opening of voltage-gated K channels. The subsequent increased efflux of K from the cytosol removes the excess positive charges from the cytosolic face of the plasma membrane (i.e., makes it more negative), thereby restoring the inside-negative resting potential. Actually, for a brief instant th ...
Biology 2401 Anatomy and Physiology I notes
... ions and molecules on either side of the membrane (chemical concentration gradient and electrical gradient = electrochemical gradient) - sodium-potassium pumps move 3 sodium (Na+) ions out and 2 potassium (K+) ions in (these pumps require ATP energy) - some K+ leaks out through K+ leak channels (ope ...
... ions and molecules on either side of the membrane (chemical concentration gradient and electrical gradient = electrochemical gradient) - sodium-potassium pumps move 3 sodium (Na+) ions out and 2 potassium (K+) ions in (these pumps require ATP energy) - some K+ leaks out through K+ leak channels (ope ...
Appendix Basics of the Nervous System
... molecule, show as a ball (the phosphate part) and two sticks (the lipid part) is the key to the membrane. The phosphate part is slightly negatively charged while the lipid part is electrically neutral. The importance of this feature of the molecule comes from the fact that is surrounded by water mol ...
... molecule, show as a ball (the phosphate part) and two sticks (the lipid part) is the key to the membrane. The phosphate part is slightly negatively charged while the lipid part is electrically neutral. The importance of this feature of the molecule comes from the fact that is surrounded by water mol ...
Schwann cells
... The unit of measurement of potential difference is the volt (V), and the transmembrane potential of a neuron is usually near 0.07 V. Such a value is usually expressed as –70 mV (or –70 millivolts—thousandths of a volt) with the minus sign indicating that the interior is negatively charged. ...
... The unit of measurement of potential difference is the volt (V), and the transmembrane potential of a neuron is usually near 0.07 V. Such a value is usually expressed as –70 mV (or –70 millivolts—thousandths of a volt) with the minus sign indicating that the interior is negatively charged. ...
Overview of the Nervous System (the most important system in the
... Nervous System Tissue: Gray & White Matter ...
... Nervous System Tissue: Gray & White Matter ...
Exam I
... 16) Both gates of the voltage-gated Na+ channels are open. 17) Which of the following is a true statement? A) Ion channels have slower effects than do metabotropic receptors. B) Cations passing through an ion channel will always cause an EPSP. C) Voltage-gated channels open when glutamate binds to t ...
... 16) Both gates of the voltage-gated Na+ channels are open. 17) Which of the following is a true statement? A) Ion channels have slower effects than do metabotropic receptors. B) Cations passing through an ion channel will always cause an EPSP. C) Voltage-gated channels open when glutamate binds to t ...
Chapter 6
... • Cones - Three types; red, green, & blue, distinguish colors but are not as sensitive, high acuity day vision; respond to selectively various wavelengths of light • Color vision depends on the three cone types various ratios of stimulation in response to different wavelengths • Photoreceptors conta ...
... • Cones - Three types; red, green, & blue, distinguish colors but are not as sensitive, high acuity day vision; respond to selectively various wavelengths of light • Color vision depends on the three cone types various ratios of stimulation in response to different wavelengths • Photoreceptors conta ...
************G*** #********** #**************b
... Beginning in the late distal tubules and continuing It occurs at the luminal membrane of the tubular cell Hydrogen ions are transported directly by a specific protein, a hydrogen-transporting ATPase (proton pump). ...
... Beginning in the late distal tubules and continuing It occurs at the luminal membrane of the tubular cell Hydrogen ions are transported directly by a specific protein, a hydrogen-transporting ATPase (proton pump). ...
Nervous System Intro
... • White matter of the brain and spinal cord is formed from aggregations of myelinated axons from many neurons. • The lipid part of myelin imparts the white appearance. ...
... • White matter of the brain and spinal cord is formed from aggregations of myelinated axons from many neurons. • The lipid part of myelin imparts the white appearance. ...
Readings to Accompany “Nerves” Worksheet (adapted from France
... membrane that separates the cytoplasm inside from the extracellular fluids outside the nerve cell, thereby creating two chemically different areas. Each area has differing amounts of potassium and sodium ions and other charged substances, with the inside of the cell being more negatively charged tha ...
... membrane that separates the cytoplasm inside from the extracellular fluids outside the nerve cell, thereby creating two chemically different areas. Each area has differing amounts of potassium and sodium ions and other charged substances, with the inside of the cell being more negatively charged tha ...
MS Word Version - Interactive Physiology
... c. Closing of voltage-gated K+ channels ___________ ...
... c. Closing of voltage-gated K+ channels ___________ ...
Action Potentials
... • Opening sodium channel produces graded potential • Resting membrane exposed to chemical • Sodium channel opens • Sodium ions enter the cell • Transmembrane potential rises ...
... • Opening sodium channel produces graded potential • Resting membrane exposed to chemical • Sodium channel opens • Sodium ions enter the cell • Transmembrane potential rises ...
Chapter 9 - Nervous System
... B. The brain can be divided into the cerebrum (largest portion and associated with higher mental functions), the diencephalon (processes sensory input), the cerebellum (coordinates muscular activity), and the brain stem (coordinates and regulates visceral activities). C. Structure of the Cerebrum (p ...
... B. The brain can be divided into the cerebrum (largest portion and associated with higher mental functions), the diencephalon (processes sensory input), the cerebellum (coordinates muscular activity), and the brain stem (coordinates and regulates visceral activities). C. Structure of the Cerebrum (p ...
13-1 CHAPTER 13 SYNAPSES The nervous system consists of
... to be the gap junction. A schematic diagram of a gap junction (sometimes called a connexon) is shown in Figure 13-3. The membranes of the two cells involved come extremely close or may actually fuse together. X-ray diffraction studies suggest that membrane ionic channels (perhaps sodium channels) of ...
... to be the gap junction. A schematic diagram of a gap junction (sometimes called a connexon) is shown in Figure 13-3. The membranes of the two cells involved come extremely close or may actually fuse together. X-ray diffraction studies suggest that membrane ionic channels (perhaps sodium channels) of ...
powerpoint file lecture 3
... At a typical endplate, the current is -500,000 pA and the single channel current is -2.7 pA so ~ 200,000 individual ACh receptors open to make the smooth endplate current ...
... At a typical endplate, the current is -500,000 pA and the single channel current is -2.7 pA so ~ 200,000 individual ACh receptors open to make the smooth endplate current ...
Increased leak conductance alters ISI variability.
... an action potential May occur before (early) or after (delayed) full repolarization Common in cardiac muscles Sometimes occurs in tissues not normally excitable ...
... an action potential May occur before (early) or after (delayed) full repolarization Common in cardiac muscles Sometimes occurs in tissues not normally excitable ...
Resting potential
The relatively static membrane potential of quiescent cells is called the resting membrane potential (or resting voltage), as opposed to the specific dynamic electrochemical phenomena called action potential and graded membrane potential.Apart from the latter two, which occur in excitable cells (neurons, muscles, and some secretory cells in glands), membrane voltage in the majority of non-excitable cells can also undergo changes in response to environmental or intracellular stimuli. In principle, there is no difference between resting membrane potential and dynamic voltage changes like action potential from a biophysical point of view: all these phenomena are caused by specific changes in membrane permeabilities for potassium, sodium, calcium, and chloride ions, which in turn result from concerted changes in functional activity of various ion channels, ion transporters, and exchangers. Conventionally, resting membrane potential can be defined as a relatively stable, ground value of transmembrane voltage in animal and plant cells.Any voltage is a difference in electric potential between two points—for example, the separation of positive and negative electric charges on opposite sides of a resistive barrier. The typical resting membrane potential of a cell arises from the separation of potassium ions from intracellular, relatively immobile anions across the membrane of the cell. Because the membrane permeability for potassium is much higher than that for other ions (disregarding voltage-gated channels at this stage), and because of the strong chemical gradient for potassium, potassium ions flow from the cytosol into the extracellular space carrying out positive charge, until their movement is balanced by build-up of negative charge on the inner surface of the membrane. Again, because of the high relative permeability for potassium, the resulting membrane potential is almost always close to the potassium reversal potential. But in order for this process to occur, a concentration gradient of potassium ions must first be set up. This work is done by the ion pumps/transporters and/or exchangers and generally is powered by ATP.In the case of the resting membrane potential across an animal cell's plasma membrane, potassium (and sodium) gradients are established by the Na+/K+-ATPase (sodium-potassium pump) which transports 2 potassium ions inside and 3 sodium ions outside at the cost of 1 ATP molecule. In other cases, for example, a membrane potential may be established by acidification of the inside of a membranous compartment (such as the proton pump that generates membrane potential across synaptic vesicle membranes).