Term
|
Definition
fluid = lipids
mosaic = large diversity of proteins |
|
|
Term
|
Definition
Depends on temperature: increase T -> increase fluidity
Depends on lipid composition:
increase cholesterol -> decrease fluidity
increase Cis C=C -> increase fluidity
increase length of FA -> decrease fluidity |
|
|
Term
|
Definition
| constantly bobbing from left to right |
|
|
Term
|
Definition
| flip from one layer of phospholipid bilayer to another, rare |
|
|
Term
|
Definition
Diverse Functions: transport, enzymatic activity, communication, cell-cell recognition, attachment
Two classes: integral membrane proteins, peripheral membrane proteins |
|
|
Term
| Integral Membrane Proteins |
|
Definition
| Integrated into membrane, can be transmembrane |
|
|
Term
|
Definition
| integral proteins that reach all the way across a membrane |
|
|
Term
| Peripheral Membrane Proteins |
|
Definition
| outside surface of membrane, not embedded, loosely bound to surface |
|
|
Term
|
Definition
short, branched chains of sugars attached to lipids or proteins
Consist of: glycolipids, glycoproteins
Function: cell-cell recognition
only found in PM, always on outside of the cell, sugars are pointing out |
|
|
Term
|
Definition
| Distinct inside and outside faces: cytosolic or extracellular |
|
|
Term
|
Definition
| cell communication, cell recognition, cell adhesion, metabolic functions, regulation of movement in/out |
|
|
Term
|
Definition
| selectively permeable due to structure, traffic across membrane depends on the lipid bilayer and transport proteins |
|
|
Term
|
Definition
2 layers of phospholipids with hydrophobic core
allow nonpolar substances to pass through cell |
|
|
Term
|
Definition
| polar adn charged ions adn molecules |
|
|
Term
|
Definition
| transport molecules by changing shape |
|
|
Term
|
Definition
| hollow tube that transports molecules |
|
|
Term
|
Definition
diffusion of a substance across a membrane with no energy investment
exergonic
move down the gradient |
|
|
Term
|
Definition
passive transport
the tendency of a substance to move down its gradient form more concentrated to less concentrated |
|
|
Term
|
Definition
| unaided diffusion through the phospholipid bilayer, no transport proteins involved |
|
|
Term
|
Definition
speed up movement of hydrophilic molecules across membranes, require transport proteins
how we move charged and polar substances |
|
|
Term
|
Definition
diffusion of water across a selectively permeable membrane
diffuses from low solute concentration to high concentration |
|
|
Term
|
Definition
| water movement important for cell structure and funciton |
|
|
Term
|
Definition
| the ability of a surrounding solution to cause a cell to gain or lose water |
|
|
Term
|
Definition
| solute and solvent are equally distributed |
|
|
Term
|
Definition
solution that has more solute than solvent
Ex) more salt than water |
|
|
Term
|
Definition
more solvent than solute
Ex) more water than salt |
|
|
Term
|
Definition
use energy to move up the gradient
requires carrier proteins
|
|
|
Term
|
Definition
Direct
ATP is direct energy source
use ion pumps |
|
|
Term
|
Definition
Na-K and H pumps
contribute to membrane potential, voltage difference across a memrane |
|
|
Term
|
Definition
| spatial variation of both electrical potential and chemical concentration across a membrane |
|
|
Term
| Secondary Active Transport |
|
Definition
Indirect or co-transport
gradient is direct energy source
couples the diffusion of one substance to the active transport of another substance |
|
|
Term
|
Definition
| transport of large molecules or many molecules across membranes via vesicle formation and fusion |
|
|
Term
|
Definition
| release of molecules out of the cell by the fusion of vesicles with the plasma membrane |
|
|
Term
|
Definition
| the uptake of molecules by the formation of intracellular vesicles form the plasma membrane |
|
|
