1.3 Facilitated diffusion Flashcards
(11 cards)
Which way does it go in a gradient?
Down.
What makes it different to normal diffusion?
It happens at specific points on the plasma membrane where there are special protein molecules.
What proteins are used in facilitated diffusion?
Channel proteins.
What fill channel proteins?
Water.
Why are channel proteins filled with water?
To allow water-soluble ions and molecules to pass through.
Are channel proteins selective?
Yes.
What does it mean if a channel protein is selective?
They only open in presence of specific molecules.
Channel proteins consist of pores lined with what?
Polar groups.
Why are channel proteins pores lined with polar groups?
Because the polar groups are hydrophilic.
What is facilitated diffusion used on?
Large or charged particles as they cannot pass through lipids.
Some channels are gated. What does this mean?
They will only open when appropriately stimulated.
