Cell Surface Membranes - 07/11/23 Flashcards
What kind of name (model) is given to cell surface membranes?
Fluid Mosaic Model
What is the main function of cell membrane?
Controlling the movement of substances in and out of the cell/organelle
What two compounds can move straight through Phospholipid Bilayer? (2)
1) O2
2) CO2
Why can O2 and CO2 only move through Phospholipid Membrane? (2)
It’s:
1) Small
2) Non-Polar
What is a channel protein?
A protein that allows the transport of ions/water soluble molecules by facilitated diffusion
What are the two types of Transport Proteins?
1) Carrier proteins
2) Channel proteins
What are intrinsic and extrinsic proteins? (2)
1) Intrinsic - Proteins integrated throughout the membrane
2) Extrinsic - Proteins on the surface of membranes
What is a type of intrinsic protein and what does it allow?
Intrinsic proteins include carrier proteins which allow substances to cross the membranes
What are Gated Channel Proteins?
A channel proteins that opens and closes to allow movement of certain substances
The cell membranes is comprised of phospholipids in which the ___________ heads point outwards and the ___________ tails point inwards.
1) hydrophilic
2) hydrophobic
What does the phospholipid structure allow and not allow to pass through the membrane? How does this help membrane?
1) Allows lipid soluble molecules, but not water soluble molecules.
2) It means membrane is flexible and self-sealing
What does a Carrier Protein do?
It binds specific molecules, changes the shape and releases them on opposite side of membrane
What are the main functions of proteins in cell membrane? (3)
1) Aids movement across the membrane
2) Provides mechanical support
3) Acts in conjunction with glycolipids as receptors
What does Fluid and Mosaic mean in Fluid Mosaic Model? (2)
1) Fluid - phospholipids/proteins can move freely within membrane
2) Mosaic - Comprised of different parts (e.g. proteins)
What do carrier proteins use to do Active Transport?
ATP
