passive diffusion & active transport Flashcards
what are the 2 types of passive diffusion?
- facilitated diffusion
- diffusion
what is diffusion?
balancing # of molecules on both sides of a semi-permeable membrane
what is a solution?
substance that contains 1 or more molecules
what is a solvent?
the dissolving agent of the solute
what is a solute?
substance inside the cell that is dissolved into a solution, can be gas, liquid, or solid
solutes are also what?
molecules
what is an aqueous solution?
a solution where the solvent is water
in simple passive diffusion what concentration will the molecules move from?
high –> low concentration (moving down concentration gradient)
what is net diffusion?
when the flow of molecules in one direction is greater than the flow of molecules in the other direction
what is dynamic equilibrium?
the state of balance where solutes will continue moving at an equal rate
what type of diffusion is facilitated diffusion?
where proteins transports have to be used to transport polar molecules or ions (solutes)
what are the 2 types of protein transporters used in facilitated diffusion?
- channel proteins
- carrier proteins
what are the 2 types of channel proteins in facilitated diffusion?
- simple channel protein
- gated channel protein
what is channel proteins in facilitated diffusion?
allows a certain solute to move from high –> low concentration by using a protein
what is a simple channel protein from facilitated diffusion?
simply allows for solutes to move through, no need for a stimulus
what is a gated channel protein from facilitated diffusion?
a gate for molecules/ions to go through, but can only be opened by an electrical stimulus or chemical
what are carrier proteins in facilitated diffusion?
allows a specific solute to bind to a binding site
what is extracellular fluid?
fluid on the outside of the cell
what is intracellular fluid?
fluid on the inside of the cell
when solutes pass through the membrane, does it save more energy to go through a transporter (facilitated diffusion) or without a transporter (diffusion)?
saves more Gibbs free energy to go through a transporter
is energy required for a passive facilitated diffusion protein channel?
no
what are the 2 types of active transport?
- primary
- secondary
is energy needed for active transport?
yes, ATP is needed
what is another term for concentration gradient?
electrochemical gradient
what is a type of active primary protein channel?
sodium-potassium pump (ATPase)
during active primary transport how is energy released?
by ATP hydrolysis which allows another solute to move against the gradient
what are the 4 steps for active primary transport?
- solute bind to channel
- phosphate group is attached to the transporter
- ATP is used to flip the transporter
- solute is released
what is the main part of active secondary transport?
a solute moving down the gradient will let out energy to power the transporter to allow another solute moving up the gradient
what are the 3 types of active secondary transport?
- uniporter
- symporter
- antiporter
what is the uniporter?
moving one type of solute up or down the gradient
what is the symporter?
moves 2 or more molecules in the same direction
what is the antiporter?
moves 2 or more molecules in opposite directions
the symporter and antiporter are also what?
co-transporters because they transport 2 or more molecules
