BSCI170 Passive and Active Transport

passive transportation

requires transport proteins, selective for solutes, requires energy from the cell to move solutes

channel proteins

mostly for ions, creates a hole in the membrane where small ions and water can pass through

carrier proteins

transport molecules too large to go through a channel, when it interacts with its solute it will change shape and push or carry the solute through the membrane

uniport

only one specific solute can move across the membrane through this protein

symport

2 molecules move in the same direction

antiport

2 molecules move in opposite directions

protein pumps

go against the concentration gradient and requires metabolic energy that comes from ATP

co-transport

2 or more solutes transported by one protein, one solute moves while the 2nd can be there to provide an energy source

secondary transport

indirect energy source stored in the ion gradient

proton pump

moves H+ across the membrane to create a difference in concentration, powered by ATP making this protein change shape and push H+ back out