The Nervous System - El Camino College
... #3 is actually a physical force called diffusion – substances flow down their concentration gradient – that is, from areas of higher concentration to areas of lower concentration. #4 is also a physical force involving electrical charge – substances flow away from areas with the same electrical c ...
... #3 is actually a physical force called diffusion – substances flow down their concentration gradient – that is, from areas of higher concentration to areas of lower concentration. #4 is also a physical force involving electrical charge – substances flow away from areas with the same electrical c ...
IB104 - Lecture 9 - Membranes Introduction The phospolipid bilayer
... 11. Phagocytosis is the process whereby cells envelop and ingest other cells, for example, amoebae or white blood cells eating bacteria. Once engulfed and surrounded by a part of the cell membrane that buds off as a vesicle inside the cell, the bacteria are digested by protein enzymes in a lysosome ...
... 11. Phagocytosis is the process whereby cells envelop and ingest other cells, for example, amoebae or white blood cells eating bacteria. Once engulfed and surrounded by a part of the cell membrane that buds off as a vesicle inside the cell, the bacteria are digested by protein enzymes in a lysosome ...
Cells: The Living Units: Part A
... • Binding of substrate causes shape change in carrier Facilitated Diffusion Using Channel Proteins • Aqueous channels formed by transmembrane proteins selectively transport ions or water • Two types: • Leakage channels • Always open • Gated channels • Controlled by chemical or electrical signals ...
... • Binding of substrate causes shape change in carrier Facilitated Diffusion Using Channel Proteins • Aqueous channels formed by transmembrane proteins selectively transport ions or water • Two types: • Leakage channels • Always open • Gated channels • Controlled by chemical or electrical signals ...
Diffusion
... 1. Chemical gradient – concentration of ion 2. Electrical gradient – charge of ion 3. Electrochemical gradient – Both Electrical charge and concentration gradient ...
... 1. Chemical gradient – concentration of ion 2. Electrical gradient – charge of ion 3. Electrochemical gradient – Both Electrical charge and concentration gradient ...
klathrop/Plasma Membrane unit Vocabulary
... Hypotonic –refers to a solution having a lower concentration of dissolved particles than the cytoplasm of a cell. (Usually causes the free water to move into the cell.) Isotonic –refers to a solution that has the same concentration as the cytoplasm of a cell. Hypertonic –refers to a solution having ...
... Hypotonic –refers to a solution having a lower concentration of dissolved particles than the cytoplasm of a cell. (Usually causes the free water to move into the cell.) Isotonic –refers to a solution that has the same concentration as the cytoplasm of a cell. Hypertonic –refers to a solution having ...
Passive vs Active Transport
... Solution Differences & Cells • solvent + solute = solution • Hypotonic – Solutes in cell more than outside – Outside solvent will flow into cell ...
... Solution Differences & Cells • solvent + solute = solution • Hypotonic – Solutes in cell more than outside – Outside solvent will flow into cell ...
The Cell Membrane, Passive Transport and Active Transport
... Ion channels are doughnut-shaped transport proteins that have a pore through which ions can cross the cell membrane. Some are always open, some are gated. The gated channels may open or close due to many stimuli - stretching, electrical charges, or when specific molecules bind to the ion channels. T ...
... Ion channels are doughnut-shaped transport proteins that have a pore through which ions can cross the cell membrane. Some are always open, some are gated. The gated channels may open or close due to many stimuli - stretching, electrical charges, or when specific molecules bind to the ion channels. T ...
Chapter 5 Homeostasis and Cell Transport
... Chapter 5 Homeostasis and Cell Transport Chapter 5: Homeostasis and Cell Transport Explain how an equilibrium is established as a result of diffusion. Distinguish between diffusion and osmosis. Explain how substances can cross the cell membrane through facilitated diffusion. I. PASSIVE TRANSPORT ...
... Chapter 5 Homeostasis and Cell Transport Chapter 5: Homeostasis and Cell Transport Explain how an equilibrium is established as a result of diffusion. Distinguish between diffusion and osmosis. Explain how substances can cross the cell membrane through facilitated diffusion. I. PASSIVE TRANSPORT ...
LEARNING GOALS - Cell Membranes
... Passive transport plays a primary role in the import of resources and the export of wastes. Membrane proteins play a role in facilitated diffusion of charged and polar molecules through a membrane. (Examples include glucose transport and Na+/K+ transport.) 3. External environments can be hypotonic, ...
... Passive transport plays a primary role in the import of resources and the export of wastes. Membrane proteins play a role in facilitated diffusion of charged and polar molecules through a membrane. (Examples include glucose transport and Na+/K+ transport.) 3. External environments can be hypotonic, ...
cell-transport-g9
... region of their lower concentration (concentrated solution), through a partially permeable membrane’ ...
... region of their lower concentration (concentrated solution), through a partially permeable membrane’ ...
Direction of Osmosis
... • A molecule binds to a carrier protein on one side of the cell membrane. • Carrier Protein • specific for one type of molecule • changes its shape and transports the molecule ...
... • A molecule binds to a carrier protein on one side of the cell membrane. • Carrier Protein • specific for one type of molecule • changes its shape and transports the molecule ...
ppt
... The Electrical Nature of Nerves Neurons use electrical signals to communicate with other neurons, muscles, and glands. The signals, called nerve impulses, involve changes in the amount of electric charge across a cell’s plasma membrane. ...
... The Electrical Nature of Nerves Neurons use electrical signals to communicate with other neurons, muscles, and glands. The signals, called nerve impulses, involve changes in the amount of electric charge across a cell’s plasma membrane. ...
Topic 8.1 Neurones and nervous responses File
... • K+ channels– Are open. K diffuses out down the concentration gradient resulting in increased negative charge inside the axon, so some K are attracted back in – moving down the electrical gradient. Eventually a electrochemical equilibrium is reached (no gradient)- -70mv and there is no net movement ...
... • K+ channels– Are open. K diffuses out down the concentration gradient resulting in increased negative charge inside the axon, so some K are attracted back in – moving down the electrical gradient. Eventually a electrochemical equilibrium is reached (no gradient)- -70mv and there is no net movement ...
Editorial What is the true resting potential of small cells?
... and Kawaguchi 1996) and the free intracellular Ca2+ concentration (see Kamouchi et al. 1999) but is thought to control various cellular functions such as apoptosis and proliferation (Ghiani et al. 1999; Wang et al. 1999). It is now clear that the potential across the membrane of a cell is, at any in ...
... and Kawaguchi 1996) and the free intracellular Ca2+ concentration (see Kamouchi et al. 1999) but is thought to control various cellular functions such as apoptosis and proliferation (Ghiani et al. 1999; Wang et al. 1999). It is now clear that the potential across the membrane of a cell is, at any in ...
Unit 2-Week 1 Notes Sheets
... - Nerve Impulse Axon Axon Terminal Release Neurotransmitter ...
... - Nerve Impulse Axon Axon Terminal Release Neurotransmitter ...
Transport Unit Study Guide
... membrane and which kind need to use a transport protein Be able to explain the processes of diffusion, facilitated diffusion, osmosis, active transport, endocytosis, and exocytosis and give examples Be able to predict the effect of a hypotonic, isotonic or hypertonic solution on a cell Be able to di ...
... membrane and which kind need to use a transport protein Be able to explain the processes of diffusion, facilitated diffusion, osmosis, active transport, endocytosis, and exocytosis and give examples Be able to predict the effect of a hypotonic, isotonic or hypertonic solution on a cell Be able to di ...
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.