Intro Membranes WRLa..
... and anions. – All cells – Can primarily be attriubuted to • Na/K exchange pump: pumps more cations out than anions in. • Differences in permeability to Na and K: cell is much more permeable to K than to Na; the concentration gradient (K our) is balanced by the attraction of anions inside. • Membrane ...
... and anions. – All cells – Can primarily be attriubuted to • Na/K exchange pump: pumps more cations out than anions in. • Differences in permeability to Na and K: cell is much more permeable to K than to Na; the concentration gradient (K our) is balanced by the attraction of anions inside. • Membrane ...
Name____________________________________________
... Which pair of characteristics are correct for the cellular processes of exocytosis and endocytosis? ...
... Which pair of characteristics are correct for the cellular processes of exocytosis and endocytosis? ...
Histology of Nervous Tissue
... • Permeability of K+ 50-100 > than Na+ (leakage channels) – K+ equilibrium potential (-90 mV) has greatest influence over resting potential • Membrane permeability greater for K+ than Na+ or Cl– Na/K electrogenic pump moves ions in 3:2 ratio – Anions (Cl-) have little effect Ions Across Membrane (gr ...
... • Permeability of K+ 50-100 > than Na+ (leakage channels) – K+ equilibrium potential (-90 mV) has greatest influence over resting potential • Membrane permeability greater for K+ than Na+ or Cl– Na/K electrogenic pump moves ions in 3:2 ratio – Anions (Cl-) have little effect Ions Across Membrane (gr ...
没有幻灯片标题
... mechanism of Na+-K+ pumping of the enzyme, mainly supposing that the enzyme cycles between two conformations, a phosphorylated one binding to K+ with high affinity (from the outside face of the cell, and to Na+ with low affinity, thus releasing Na+ ions to the outside face), and a dephosphorylated o ...
... mechanism of Na+-K+ pumping of the enzyme, mainly supposing that the enzyme cycles between two conformations, a phosphorylated one binding to K+ with high affinity (from the outside face of the cell, and to Na+ with low affinity, thus releasing Na+ ions to the outside face), and a dephosphorylated o ...
9/7
... Various combinations of lipids can result in differences in rigidity and thickness of membrane ...
... Various combinations of lipids can result in differences in rigidity and thickness of membrane ...
Membrane Structure and Function Cell Membrane: a Phospholipid
... • Channel proteins: form channels to allow specific ions or molecules to pass through the membrane. • Carrier proteins: bind substrates to move them through the membrane. • Movement through these proteins occurs by both active and passive transport ...
... • Channel proteins: form channels to allow specific ions or molecules to pass through the membrane. • Carrier proteins: bind substrates to move them through the membrane. • Movement through these proteins occurs by both active and passive transport ...
4.2 How to get other molecules across membranes
... 2) Channels or pores may also exist in membrane to allow transport ...
... 2) Channels or pores may also exist in membrane to allow transport ...
chapter-11-functional-organization-of-nervous
... receive the impulse Most are axo-dendritic or axo-somatic ...
... receive the impulse Most are axo-dendritic or axo-somatic ...
power point for chap 11
... • Ions flow along their chemical gradient when they move from an area of high concentration to an area of low concentration • Ions flow along their electrical gradient when they move toward an area of opposite charge ...
... • Ions flow along their chemical gradient when they move from an area of high concentration to an area of low concentration • Ions flow along their electrical gradient when they move toward an area of opposite charge ...
Lecture 21-Kumar - Rutgers New Jersey Medical School
... The model for membrane structure is known as the fluid mosaic model. Peripheral proteins occur on the inner or outer face of the membrane and integral proteins extend through both lipid layers. Membrane bound enzymes occur allowing structured metabolic pathways. Glycoproteins form the glycocalyx and ...
... The model for membrane structure is known as the fluid mosaic model. Peripheral proteins occur on the inner or outer face of the membrane and integral proteins extend through both lipid layers. Membrane bound enzymes occur allowing structured metabolic pathways. Glycoproteins form the glycocalyx and ...
File - Dillman Biology
... Ions can pass through the channels without contacting the hydrophobic (nonpolar) part of the cell membrane. ...
... Ions can pass through the channels without contacting the hydrophobic (nonpolar) part of the cell membrane. ...
Diffusion Demonstration
... 1) Hypertonic: A solution with a higher concentration of solute than inside the cell. • Cell will lose water 2) Hypotonic: A solution with a lower concentration of solute than inside the cell. • Cell will gain water 3) Isotonic: A solution with equal concentrations of solute when compared to inside ...
... 1) Hypertonic: A solution with a higher concentration of solute than inside the cell. • Cell will lose water 2) Hypotonic: A solution with a lower concentration of solute than inside the cell. • Cell will gain water 3) Isotonic: A solution with equal concentrations of solute when compared to inside ...
cellular transport
... A state of balance where particles move in all directions at equal rates. Selectively Permeable: Allows only certain substances to pass through it. Concentration gradient: A difference in concentration between two areas Transmembrane Protein: A protein molecule in a membrane that spans the t ...
... A state of balance where particles move in all directions at equal rates. Selectively Permeable: Allows only certain substances to pass through it. Concentration gradient: A difference in concentration between two areas Transmembrane Protein: A protein molecule in a membrane that spans the t ...
Nervous System:
... Neural Communication Ion pumps in the cell membranes of neurons release three positively charged sodium ions, while taking in only two positively charged potassium ions which creates a negative charge inside the cell. The space inside the neuron now has a resting potential, which is a kind of membr ...
... Neural Communication Ion pumps in the cell membranes of neurons release three positively charged sodium ions, while taking in only two positively charged potassium ions which creates a negative charge inside the cell. The space inside the neuron now has a resting potential, which is a kind of membr ...
Electricity within the body
... is an electrical potential difference. This due to the presence of more negative ions on the inside of the membrane than the outside , the neuron said to be polarized . The inside of the cell is typically 60 -90 mv more negative than outside. ...
... is an electrical potential difference. This due to the presence of more negative ions on the inside of the membrane than the outside , the neuron said to be polarized . The inside of the cell is typically 60 -90 mv more negative than outside. ...
Secondary active transport
... use the ion gradients established by ATPase for transport of various substances against their gradients of electrochemical potentials via transporters/ carriers. ...
... use the ion gradients established by ATPase for transport of various substances against their gradients of electrochemical potentials via transporters/ carriers. ...
the limbic system
... (a) the ionic concentration differences across the membrane, and (b) the membrane's relative permeabilities to different ions. Plasma membrane Na,K-ATPase pumps maintain intracellular sodium concentration low and potassium high. In almost all resting cells, the plasma membrane is much more permeable ...
... (a) the ionic concentration differences across the membrane, and (b) the membrane's relative permeabilities to different ions. Plasma membrane Na,K-ATPase pumps maintain intracellular sodium concentration low and potassium high. In almost all resting cells, the plasma membrane is much more permeable ...
test - Scioly.org
... Sensory nerve cells act as the decision-making cells to sum up all signals for certain stimuli. a. True b. False 6. Neuroglial eclls supporr and proVide nutfition for the a. Muscle Cells b. Glands c. Neurons d. Nephrons 7. Neurons often have many short dendrites and a long axon. a. True b. False 8. ...
... Sensory nerve cells act as the decision-making cells to sum up all signals for certain stimuli. a. True b. False 6. Neuroglial eclls supporr and proVide nutfition for the a. Muscle Cells b. Glands c. Neurons d. Nephrons 7. Neurons often have many short dendrites and a long axon. a. True b. False 8. ...
Gail`s powerpoint
... 2 K+ ions out of cell • Converts 20 – 30 % of current ATP production in resting mammals to Na+ and K+ transport • P2-Type ATPase – Alkali metal cations – Pump gets phosphorylated during cycle • D-K-T-G-T-L-T ...
... 2 K+ ions out of cell • Converts 20 – 30 % of current ATP production in resting mammals to Na+ and K+ transport • P2-Type ATPase – Alkali metal cations – Pump gets phosphorylated during cycle • D-K-T-G-T-L-T ...
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.