Lecture 4: Cellular Building Blocks
... • Transmembrane proteins span the bilayer • Peripheral membrane proteins associate with one side ...
... • Transmembrane proteins span the bilayer • Peripheral membrane proteins associate with one side ...
Test 3
... the Na+K+ ATPase is a P-type ATPase, meaning its mechanism goes through a phosphorylated intermediate and its action can be inhibited by Vanadate. It is a dimer composed of a 50,000 and a 110,000 MW subunits, both of which span the membrane. This ATPase is used to pump 3 Na+ ions out of the cell and ...
... the Na+K+ ATPase is a P-type ATPase, meaning its mechanism goes through a phosphorylated intermediate and its action can be inhibited by Vanadate. It is a dimer composed of a 50,000 and a 110,000 MW subunits, both of which span the membrane. This ATPase is used to pump 3 Na+ ions out of the cell and ...
Membrane Processes_part 1
... Power Requirement ¾The resistance (R) of an electro-dialysis stack treating a particular feed must be determined experimentally ¾If resistance (R) and current (I) are known: ...
... Power Requirement ¾The resistance (R) of an electro-dialysis stack treating a particular feed must be determined experimentally ¾If resistance (R) and current (I) are known: ...
Transport across membranes File
... small or nonpolar molecules such as , , and lipids. Water molecules, although polar, are small enough to diffuse across membranes in a manner that is not entirely understood. ■ Membranes are permeable to lipids, which can pass through the nonpolar interior of the lipid bilayer. Membrane permeability ...
... small or nonpolar molecules such as , , and lipids. Water molecules, although polar, are small enough to diffuse across membranes in a manner that is not entirely understood. ■ Membranes are permeable to lipids, which can pass through the nonpolar interior of the lipid bilayer. Membrane permeability ...
Plasma Membrane Notes (7.2)
... Selective Permeability Property of the membrane that allows certain materials to ____________ ____________ the cell while keeping others ____________ It also allows ____________ cells to perform different activities within the ____________ organism. Example: Human nerve cells respond to a cert ...
... Selective Permeability Property of the membrane that allows certain materials to ____________ ____________ the cell while keeping others ____________ It also allows ____________ cells to perform different activities within the ____________ organism. Example: Human nerve cells respond to a cert ...
A. What is a neuron? 1. A neuron is a type of cell that receives and
... 8. After the action potential, the neuron has more Na+ and fewer K+ ions inside for a short period (this is soon adjusted by the sodium-potassium pumps to the neuron's original concentration gradient). 9. Local anesthetic drugs (e.g., Novocain, Xylocaine, etc.) hinder the occurrence of action poten ...
... 8. After the action potential, the neuron has more Na+ and fewer K+ ions inside for a short period (this is soon adjusted by the sodium-potassium pumps to the neuron's original concentration gradient). 9. Local anesthetic drugs (e.g., Novocain, Xylocaine, etc.) hinder the occurrence of action poten ...
Chapter 5
... been used to study facilitated diffusion E. Some carrier-mediated active transport systems “pump” substances against their pressure gradients 1. Materials are transported from a region of low concentration to high concentration by carriermediated active transport mechanisms 2. ATP is required 3. The ...
... been used to study facilitated diffusion E. Some carrier-mediated active transport systems “pump” substances against their pressure gradients 1. Materials are transported from a region of low concentration to high concentration by carriermediated active transport mechanisms 2. ATP is required 3. The ...
Diffusion and Osmosis Worksheet
... Despite their difference in size and shape, all cells are enclosed by a cell membrane that consists of a double layer of phospholipids interspersed with proteins. Its unique structure is described as selectively permeable because it permits some substances to cross it rapidly, while others are unabl ...
... Despite their difference in size and shape, all cells are enclosed by a cell membrane that consists of a double layer of phospholipids interspersed with proteins. Its unique structure is described as selectively permeable because it permits some substances to cross it rapidly, while others are unabl ...
AP Biology Campbell 8th Edition Chapter 1 Study Guide
... action potential is generated and then propagated down the axon. The Action Potential Begins at the Axon Hillock • The action potential is generated at the axon hillock, where the density of voltagegated sodium channels is greatest. • The action potential begins when signals from the dendrites and c ...
... action potential is generated and then propagated down the axon. The Action Potential Begins at the Axon Hillock • The action potential is generated at the axon hillock, where the density of voltagegated sodium channels is greatest. • The action potential begins when signals from the dendrites and c ...
Nervous System - Academic Computer Center
... Play a role in the exchange between capillaries and neurons, synapse formation and in guiding the migration of young neurons ...
... Play a role in the exchange between capillaries and neurons, synapse formation and in guiding the migration of young neurons ...
1. If a significant amount of Cl - entered the body of a motor neuron
... a. Positively charged ions are known as anions b. The flow of ions into a cell is an example of an electrical current. c. The plasma membrane is a source of electrical resistance d. A separation of negative and positive charges is a source of potential energy. e. A typical neuron has a membrane pote ...
... a. Positively charged ions are known as anions b. The flow of ions into a cell is an example of an electrical current. c. The plasma membrane is a source of electrical resistance d. A separation of negative and positive charges is a source of potential energy. e. A typical neuron has a membrane pote ...
Chapter 12: Neural Tissue
... – K+ inside and outside of the cell are attracted to the negative charges on the inside of the cell membrane, and repelled by the positive charges on the outside of the cell membrane • indicated in white on the next slide ...
... – K+ inside and outside of the cell are attracted to the negative charges on the inside of the cell membrane, and repelled by the positive charges on the outside of the cell membrane • indicated in white on the next slide ...
PowerPoint
... • When an impulse reaches the Axon Terminal, dozen of vesicles fuse with the cell membrane and discharge the Neurotransmitter into the Synaptic Cleft (GAP). • The molecules of the neurotransmitter diffuse across the gap and attach themselves to SPECIAL RECEPTORS on the membrane of the neuron receiv ...
... • When an impulse reaches the Axon Terminal, dozen of vesicles fuse with the cell membrane and discharge the Neurotransmitter into the Synaptic Cleft (GAP). • The molecules of the neurotransmitter diffuse across the gap and attach themselves to SPECIAL RECEPTORS on the membrane of the neuron receiv ...
Characteristic for receptor cells
... • Rate of adaptation to different sweet stimuli not same, perception of sweet taste of saccharine declines more than twice as fast as sweet taste of sugar on successive samples ...
... • Rate of adaptation to different sweet stimuli not same, perception of sweet taste of saccharine declines more than twice as fast as sweet taste of sugar on successive samples ...
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.