Science Final Chapt 4
Terms
undefined, object
copy deck
- the outer boundary of cells
- plasma membrane
- made up of 2 layers of molecules called teh phospholipids
- lipid bilayer
- random movement of ions and other particles
- diffusion
- greater concentration to less
- dynamic equilibrum
- no energy required
- passive transport
- diffusion of water in and out of cells across a selectively permeable membrane
- osmosis
- use of transport proteins to aid the passage of particles across the plasma membrane
- facilitated difusion
- provides water-filled passages through which small dissolved particles like ions can diffuse
- channel proteins
- change shape to allow certain molecules to cross the plasma membrane
- carrier protein
- open to allow plassage of particles, when a "signal" molecule combines with the gate. when the signal molecule is released, the gate closes.
- gate protein
-
lesser concentration to greater concentration
energy required - active transport
- process whic the plama membrane engulfs and takes in substances from a cell's environment
- endocytosis
- takes out substances from a cell's environment
- exocytosis