plasma membrane Flashcards
plasma membrane is also called
cell membrane or plasmalemma
plasma membrane
an extremely thin, outer border of the cell that separates the intracellular and extracellular fluid compartments
composition and structure
a phospholipid bilayer with proteins interspersed throughout
functions
communication, intercellular connection, physical barrier, selective permeability
two types of membrane transport
passive and active
passive transport
does not require energy from the cell
active transport
requires energy from the cell; typically ATP
passive transport mechanisms include
simple diffusion, osmosis, and facilitated diffusion
simple diffusion
flow of molecules from high to low concentration
osmosis
movement of water molecules from high to low concentrations
facilitated diffusion
diffusion with the help from proteins
bulk transport
movement of large structures across the cell membrane
exocytosis
out of the cell; molecules leaving
endocytosis
molecules entering
forms of endocytosis
phagocytosis and pinocytosis
