Unit 5: protein mediated transport Flashcards
Why are cell membranes and transporters so important? 2 things
protection
separation of molecules
how do you get molecules in and out of cell membranes? 2 things
Diffusion
Transport
how does a transport work
tube through membrane
what gets through simple diffusion
small non polar molecules
What gets through transport proteins?
ions(K+, Na+)
small/medium molecules (glucose, amino acids)
polar
How would you build a transport protein? what kind of protein, what properties in R groups? and which secondary structure?
- Transmembrane protein, all the way through
- Nonpolar on the outside, in the lipid, vander waal bonds
- Alpha helix on left/right side
Where are transport proteins
all over the cell
What is the first question when figuring out membrane transport?
is energy required
If Energy is required what transport? If energy is not required what transport?
No energy: passive transport
Energy: active transport
If Energy is required what transport? If energy is not required what transport?
No energy: passive transport
Energy: active transport
passive transport how does it move
down/with the gradient [high] –> [low]
active transport, how does it move
up/against the gradient [low] –> [high]
After finding out transport doesn’t require energy and it passive transport what do you ask
is a protein required
In passive transport if not protein is required, what kind of diffusion
simple
small, non polar
In passive transport if protein is required, what kind of diffusion
facilitated diffusion osmosis
what does facilitated diffusion mean
transport helps it happen, ion, polar, large
Facilitated diffusion leads to what question
conformational shift?
If there is a conformational shift what is not needed
gated channels
If there is a conformational shift what is needed
protein carrier
channels/gates are like what analogy
door propped open
carriers are like what analogy
revolving door
does a carrier transporter or channel transporter: require a conformational shift to move a molecules across the membrane?
carrier transporter
carrier transporters have 2 characteristics
selective and not gated
does a carrier or channel: can be gated (locked)
Channel transporter
what types of gates does channel transporters have
ligand gate, voltage, mechano
channel transporters have 2 characteristics
Selective and passive [high]–>[low]
Active transport has 3 inner transports, what are they
Primary active transport
secondary active transport
electron driven transport
Primary active transport 5 properties
"pump" directly uses ATP [low]-->[high] (against gradient) type of carrier 2 kinds (uniport and cotransport)
uniport, what does it do
transport of 1 type of molecule
what does cotransport do
transport of 2 types of molecules
what are the kinds of cotransports
antiport: opposite direction
symport: same direction
3Na+/2K+ pump, what are the steps
- 3 na+ bind to intracellular die of pump
- ATP add phosphate to pump
- Conformational shift (flip to outside/other side)
- 3 Na+ go outside
- 2 K+ bind to extracellular side of pump
- phosphate removed
- conformational shift (flip to inside)
- 2 K+ go inside
- repeat
Secondar active transport uses what to move molecules against their gradient, how many molecules
gradients
move 2 molecules at once(antiport, symport)
Driver and Passenger of a Secondar active transport
driver[high]–>[low]
passenger[low]–>[high]
ions are really good drivers of secondary transport. Why>
ions have chemical and electrical gradients
