Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
41 Cards in this Set
- Front
- Back
|
Plasma Membrane
|
selective permeability that acts as the boundary of a cell. Fluid
|
|
|
Cholesterol
|
effects membrane fluidity depending on temp; helps separate the phospholipids so that the fatty acid chains can't come together and cyrstallize.
|
|
|
Integral Protein
|
penetrate the hydrophobic core of the lipid bilayer.
|
|
|
Peripheral protein
|
not embedded in the bilayer, just bound. bind to integral membranes.
|
|
|
Signal Transduction
|
communication with environment.
|
|
|
Intracellular joining
|
tight junctions
|
|
|
carbohydrate attached to anything
|
glyco- lipid, protein, etc.
|
|
|
Channel Proteins
|
hydrophilic carrier that specific ions or molecules can use as a tunnel.
|
|
|
Aquaporins
|
facilitate the movement of water.
|
|
|
Diffusion
|
molecules spread out evenly into the available space. refers to the movement of solute down its own concentration gradient.
|
|
|
Carrier Proteins
|
bind to molecules and change shape to shuttle them across the membrane.
|
|
|
What substances diffuse right across the membrane?
|
hydrophobic substances.
|
|
|
Passive Transport
|
goes from high concentration to low concentration.
|
|
|
Concentration Gradient
|
the difference in concentration of a substance from one area to another.
|
|
|
Osmosis
|
diffusion of water across a selectively permeable membrane.
|
|
|
Tonicity
|
ability of a solution to cause a cell to gain or lose water.
|
|
|
Isotonic Solution
|
solute conc. is the same as that inside the cell.
|
|
|
Hypertonic Solution
|
solute conc. is greater than that inside the cell; "hypertonic sucks", always takes water.
|
|
|
Hypotonic Solution
|
solute conc. is less than that inside the cell.
|
|
|
Osmoregulation
|
water balance.
|
|
|
Facilitated Diffusion
|
passive transport aided by transport proteins. no energy used.
|
|
|
Active Transport
|
moves solutes against their gradients; requires energy. only uses carrier proteins.
|
|
|
Sodium-Potassium Pump
|
moves sodium out and potassium in. active transport, for polar substances.
|
|
|
Voltage
|
electrical potential energy, seperation of opposite charges across the membrane.
|
|
|
Membrane Potential
|
voltage difference across a membrane.
|
|
|
What drives the diffusion of ions?
|
chemical force- the ion's conc. gradient; electrical force- effect of membrane potential on ion's movement.
|
|
|
Electrogenic Pump
|
transport protein that generates the voltage across a membrane.
|
|
|
Phagocytosis
|
cell engulfs particles in a vacuole.
|
|
|
Exocytosis
|
transport vesicles migrate to membrane, fuse with it, and release their contents.
|
|
|
Endocytosis
|
cells take in macromolecules by forming vesicles from the plasma membrane.
|
|
|
What does cholesterol do to a membrane?
|
lowers the temperature required for a membrane to solidify; cooler temps. maintain fluidity by preventing tight packing.
|
|
|
Cell-Cell Recognition
|
communication with other cells; recognize self vs. non-self.
|
|
|
What are the 6 major functions of membrane proteins?
|
transport, enzymatic activity, signal transduction, cell-cell recognition, intracellular joining, atachment to the cytoskeleton or ECM.
|
|
|
What organisms live in a hypotonic environment?
|
paramecium.
|
|
|
Ion channels
|
gated tunnels, stimulus causes them to open/close.
|
|
|
What has a negative charge compared to extracellular fluid?
|
cytoplasm.
|
|
|
Cotransporter protein
|
coupled transport.
|
|
|
Bulk Transport
|
large molecules cross the membrane via vesicle.
|
|
|
What are the 3 types of endocytosis?
|
phagocytosis, pinocytosis, receptor-mediated endocytosis.
|
|
|
Pinocytosis
|
cell forms vesicle around fluid.
|
|
|
What kind of fatty acid maintains fluidity better?
|
unsaturated fatty acids are more fluid at lower temps. because the double bonds prevent tight packing.
|
