Download Ch. 5 | BIOL 140 - Organization/Function of Cell and more Quizzes Biology in PDF only on Docsity!
Fluid Mosaic Model
General structure of membranes. This phospholipid bilayer is like a "lake" in which a variety of proteins "float" TERM 2
Integral membrane proteins
DEFINITION 2 Span the bilayer hydrophilic ends protrude on either side TERM 3
Peripheral membrane proteins
DEFINITION 3 do not penetrate the bilayer TERM 4
Transmembrane proteins
DEFINITION 4 May have different domains on either side of the membrane, the two sides of the membrane an have very different properties, some membrane proteins can move freely within the bilayer, while some are anchored to a specific region, some can be anchored by cytoskeleton elements. TERM 5
Homotypic
DEFINITION 5 The same molecule sticks out from both cells and forms a bond
Heterotypic
The cells have different proteins TERM 7
Tight Junctions
DEFINITION 7 Help ensure directional movement of materials. No space between 2 cells TERM 8
Desmosomes
DEFINITION 8 Like "spot welds". have spaces between cells TERM 9
Gap junction
DEFINITION 9 Allow communication. Help efficiency in sending and responding to signals TERM 10
Passive transport
DEFINITION 10 no outside energy required-diffusion
Water will diffues:
from the region of higher water conc. to the region of lower water conc. TERM 17
Isotonic
DEFINITION 17 Equal solute conc TERM 18
Hypertonic
DEFINITION 18 Higher solute conc TERM 19
Hypotonic
DEFINITION 19 lower solute conc. animal cells may burst when placed in a hypotonic solution TERM 20
Carrier proteins
DEFINITION 20 Transport polar molecules such as glucose across membranes, glucose binds to the protein, which causes it to change shape
Active trasport
Moves substances against a conc gradient-requires energy. 3 kinds of proteins: uniports, symports, antiports TERM 22
Sodium-potassium pump
DEFINITION 22 Primary active transport (requires direct participation of ATP), found in all animal cells, the "pump" is an integral membrane glycoprotein. It is an antiport TERM 23
Endocytosis
DEFINITION 23 Processes that bring molecules and cells into a eukaryotic cell. The plasma membrane folds in or invaginates around the material; forming a vesicle TERM 24
Phagocytosis
DEFINITION 24 Molecules or entire cells are engulfed. Some protists feed in this way, some white blood cells engulf foregin substances, a food vacuole or a phagosome forms, which fuses with a lysosomes TERM 25
Pinocytosis
DEFINITION 25 A vesicle forms to bring small dissolved substances or fluid into a cell. vesicles are much smaller than phagocytosis. pinocytosis is contant endothelial cells
