Nervous System Chapter 11 Answers
... Chemical gradient is formed when ions diffuse across a membrane (High to low concentration) Electrical gradient is formed when ions move toward an area of opposite charge An electrochemical gradient occurs on neural membranes due to BOTH chemical & electrical gradients 11. What is the resting membra ...
... Chemical gradient is formed when ions diffuse across a membrane (High to low concentration) Electrical gradient is formed when ions move toward an area of opposite charge An electrochemical gradient occurs on neural membranes due to BOTH chemical & electrical gradients 11. What is the resting membra ...
2. a) Protein channels help to move material across the cell
... allowing cells to identify one another 3. The plasma membrane is described to be fluid because of its lipids and membrane proteins that move laterally or sideways throughout the membrane. That means the membrane is not solid, but more like a 'fluid'. The membrane is depicted as mosaic because li ...
... allowing cells to identify one another 3. The plasma membrane is described to be fluid because of its lipids and membrane proteins that move laterally or sideways throughout the membrane. That means the membrane is not solid, but more like a 'fluid'. The membrane is depicted as mosaic because li ...
Membrane Potential
... Transfers positive charges to outside Cell’s interior becomes more negative K+ move into cell down electrical gradient Na+ move into cell down both gradients ...
... Transfers positive charges to outside Cell’s interior becomes more negative K+ move into cell down electrical gradient Na+ move into cell down both gradients ...
AP – All or nothing
... membrane, this is repolarisation • The membrane briefly becomes hyperpolarised (more negative on the inside than usual) • The Na+ / K+ channels close ...
... membrane, this is repolarisation • The membrane briefly becomes hyperpolarised (more negative on the inside than usual) • The Na+ / K+ channels close ...
Dr. Melanie D. Osterhouse presents Action potentials and
... These stimuli cause the axon hillock (start of the axon) to create an action potential The action potential continues to the end of the axon ...
... These stimuli cause the axon hillock (start of the axon) to create an action potential The action potential continues to the end of the axon ...
Biology 212: January 30, 2002
... the membrane is relatively permeable to it. Since potassium is positively charged, the result is that the inside is negative. It would be even more negative (about -85 mV is where K+ chemical gradient matches the electrical gradient) but the membrane is slightly permeable to sodium ions, and those ...
... the membrane is relatively permeable to it. Since potassium is positively charged, the result is that the inside is negative. It would be even more negative (about -85 mV is where K+ chemical gradient matches the electrical gradient) but the membrane is slightly permeable to sodium ions, and those ...
guide
... Which techniques would be good for anatomical imaging? Which techniques show the location of brain activity? Which techniques are good for showing the time course of activity? Topic Papers The questions you already have answered… Physiology Resting membrane potential – know the relative concentratio ...
... Which techniques would be good for anatomical imaging? Which techniques show the location of brain activity? Which techniques are good for showing the time course of activity? Topic Papers The questions you already have answered… Physiology Resting membrane potential – know the relative concentratio ...
13. Electrochemical Impulse
... Electrochemical Impulse It has long been known that electrical impulses are present in living organisms, but it is only within the last century that we have understood how and why neurons transmit electricity These impulses are generated using uneven concentrations of ions inside the neuron compared ...
... Electrochemical Impulse It has long been known that electrical impulses are present in living organisms, but it is only within the last century that we have understood how and why neurons transmit electricity These impulses are generated using uneven concentrations of ions inside the neuron compared ...
Nerves Powerpoint
... • All neurons release a neurotransmitter at the end of the axon! – Acetylcholine is most common and usually stimulating – Dopamine and serotonin are commonly used in the brain and may be stimulating or inhibiting – There are many others! ...
... • All neurons release a neurotransmitter at the end of the axon! – Acetylcholine is most common and usually stimulating – Dopamine and serotonin are commonly used in the brain and may be stimulating or inhibiting – There are many others! ...
Functional Organization of Nervous Tissue
... • Cells produce electrical signals called action potentials • Transfer of information from one part of body to another • Electrical properties result from ionic concentration differences across plasma membrane and permeability of membrane ...
... • Cells produce electrical signals called action potentials • Transfer of information from one part of body to another • Electrical properties result from ionic concentration differences across plasma membrane and permeability of membrane ...
M. Woodin
... • Allows the recording from a single ion channel located in the area of the patch under the pipette • As the ion channel opens or closes there will be an abrupt increase or decrease in the conductance of the patch of membrane • Ion channels can be characterized by their conductance, their open time, ...
... • Allows the recording from a single ion channel located in the area of the patch under the pipette • As the ion channel opens or closes there will be an abrupt increase or decrease in the conductance of the patch of membrane • Ion channels can be characterized by their conductance, their open time, ...
The Nervous System: Organization and Tissues
... flow ions across cellular membranes Ion channels allow the flow of ions into and out of the cell ...
... flow ions across cellular membranes Ion channels allow the flow of ions into and out of the cell ...
87881e9f4bc5cca
... concentration in the extracellular medium: usually about 100 nmol liter−1 compared with 1 mmol liter−1. Because the resting voltage is attracting the positively charged calcium ions inward, the overall result is a large electrochemical gradient favoring calcium entry into cells. ...
... concentration in the extracellular medium: usually about 100 nmol liter−1 compared with 1 mmol liter−1. Because the resting voltage is attracting the positively charged calcium ions inward, the overall result is a large electrochemical gradient favoring calcium entry into cells. ...
Exam 1 suggested answers (2010)
... 2.a. A synapse with Erev more negative than threshold is inhibitory. Even though it results in a depolarization when the neuron is at resting potential, this makes it harder for the neuron to depolarize to levels less negative than the E rev, thus making it harder to reach threshold. b. In this situ ...
... 2.a. A synapse with Erev more negative than threshold is inhibitory. Even though it results in a depolarization when the neuron is at resting potential, this makes it harder for the neuron to depolarize to levels less negative than the E rev, thus making it harder to reach threshold. b. In this situ ...
Cells B
... leakage channels. Loss of K+ results in a net negative charge, and therefore negative voltage, inside cell. ...
... leakage channels. Loss of K+ results in a net negative charge, and therefore negative voltage, inside cell. ...
SBI 4U Homeostasis 2
... • A system that uses ATP in order to keep the electrical potential difference across the membrane. • For every three sodium ions transported out of the cell, two potassium ions are transported into the cell. • An overall positive charge is going to accumulate on the outside of the cell membrane and ...
... • A system that uses ATP in order to keep the electrical potential difference across the membrane. • For every three sodium ions transported out of the cell, two potassium ions are transported into the cell. • An overall positive charge is going to accumulate on the outside of the cell membrane and ...
Vm = Vin – Vout V = IR V = I/g Ix = gx (Vm – Ex)
... where PK, PNa and PCl = permeabilities for K+, Na+ and Cl- ions, respectively. ...
... where PK, PNa and PCl = permeabilities for K+, Na+ and Cl- ions, respectively. ...
Class Notes 2
... cell at 100 u/sec. When the cell is damaged, an action potential is generated and the streaming stops. Protoplasmic streaming is produced by actinomyosin as found in animal muscle. Streaming is inhibited when Ca++ moves into the cytoplasm activating a protein kinase that phosphorylates myosin so it ...
... cell at 100 u/sec. When the cell is damaged, an action potential is generated and the streaming stops. Protoplasmic streaming is produced by actinomyosin as found in animal muscle. Streaming is inhibited when Ca++ moves into the cytoplasm activating a protein kinase that phosphorylates myosin so it ...
chapter 48
... Astrocytes: are found within the CNS and provide structural and metabolic support as well as forming of tight junctions to help form the blood-brain barrier. They also communicate with one another via ...
... Astrocytes: are found within the CNS and provide structural and metabolic support as well as forming of tight junctions to help form the blood-brain barrier. They also communicate with one another via ...
Ca channel
... Archetypal channel pore is just one or two atoms wide at its narrowest point. It conducts a specific species of ion and conveys them through the membrane single file--nearly as fast as the ions move through free fluid. In some ion channels, access to the pore is governed by a "gate," which may be op ...
... Archetypal channel pore is just one or two atoms wide at its narrowest point. It conducts a specific species of ion and conveys them through the membrane single file--nearly as fast as the ions move through free fluid. In some ion channels, access to the pore is governed by a "gate," which may be op ...
Membrane potential
Membrane potential (also transmembrane potential or membrane voltage) is the difference in electric potential between the interior and the exterior of a biological cell. With respect to the exterior of the cell, typical values of membrane potential range from –40 mV to –80 mV.All animal cells are surrounded by a membrane composed of a lipid bilayer with proteins embedded in it. The membrane serves as both an insulator and a diffusion barrier to the movement of ions. Ion transporter/pump proteins actively push ions across the membrane and establish concentration gradients across the membrane, and ion channels allow ions to move across the membrane down those concentration gradients. Ion pumps and ion channels are electrically equivalent to a set of batteries and resistors inserted in the membrane, and therefore create a voltage difference between the two sides of the membrane.Virtually all eukaryotic cells (including cells from animals, plants, and fungi) maintain a non-zero transmembrane potential, usually with a negative voltage in the cell interior as compared to the cell exterior ranging from –40 mV to –80 mV. The membrane potential has two basic functions. First, it allows a cell to function as a battery, providing power to operate a variety of ""molecular devices"" embedded in the membrane. Second, in electrically excitable cells such as neurons and muscle cells, it is used for transmitting signals between different parts of a cell. Signals are generated by opening or closing of ion channels at one point in the membrane, producing a local change in the membrane potential. This change in the electric field can be quickly affected by either adjacent or more distant ion channels in the membrane. Those ion channels can then open or close as a result of the potential change, reproducing the signal.In non-excitable cells, and in excitable cells in their baseline states, the membrane potential is held at a relatively stable value, called the resting potential. For neurons, typical values of the resting potential range from –70 to –80 millivolts; that is, the interior of a cell has a negative baseline voltage of a bit less than one-tenth of a volt. The opening and closing of ion channels can induce a departure from the resting potential. This is called a depolarization if the interior voltage becomes less negative (say from –70 mV to –60 mV), or a hyperpolarization if the interior voltage becomes more negative (say from –70 mV to –80 mV). In excitable cells, a sufficiently large depolarization can evoke an action potential, in which the membrane potential changes rapidly and significantly for a short time (on the order of 1 to 100 milliseconds), often reversing its polarity. Action potentials are generated by the activation of certain voltage-gated ion channels.In neurons, the factors that influence the membrane potential are diverse. They include numerous types of ion channels, some of which are chemically gated and some of which are voltage-gated. Because voltage-gated ion channels are controlled by the membrane potential, while the membrane potential itself is influenced by these same ion channels, feedback loops that allow for complex temporal dynamics arise, including oscillations and regenerative events such as action potentials.