2.3 Transport Across Cell Membranes Flashcards
What model do all membranes have
Fluid-mosaic
What are the major components to the cell membrane
- Phospholipid Bilayer
- Channel Protein
- Carrier Protein
- Glycoprotein
- Glycolipid
- Cholesterol
Name the component of the cell membrane
Phospholipid Bilayer
Name the component of the cell membrane
Channel Protein
Name the component of the cell membrane
Glycoprotein
Name the component of the cell membrane
Carrier Protein
Name the component of the cell membrane
Glycolipid
Name the component of the cell membrane
Cholesterol
Describe the arrangement of phospholipid molecules in the phospholipid bilayer
- Two layers of phospholipids
Hydrophilic heads face outside - Hydrophobic tails face inside
Describe and explain the advantages of the phospholipid bilayer in the cell membrane
- Selectively-permeable barrier
- Only non-polar molecules are able to pass through via simple diffusion
- Bilayer is fluid
- Can bend to take up different shapes, forming vesicles
Describe and explain the advantages of channel proteins in the cell membrane
- Protein through bilayers
- Allows water soluble substances through via faccilitated diffusion
Describe and explain the advantages of carrier proteins in the cell membrane
- Protein through bilayer
- Allows substances to move through via faccilitated diffusion and active transport
Describe and explain the advantages of glycoproteins in the cell membrane
- Protein with short carbohydrate chain
- Cell recognition and signalling
- Cell attachment
Describe and explain the advantages of glycolipids in the cell membrane
- Phospholipid with short carbohydrate chain
- Cell recognition and signalling
- Cell attachment
Describe and explain the advantages of cholesterol in the cell membrane
Regulates membrane fluidity
Simple diffusion: Movement of molecules
- Along concentration gradient
- From higher concentration to lower concentration
Simple diffusion: Active or passive
- Passive
- No ATP hydrolysed
Simple diffusion: Movement through what
Diffuse through phospholipid bilayer
Simple diffusion: Type of molecule
Non-polar
Faccilitated diffusion: Movement of molecules
- Along concentration gradient
- From higher concentration to lower concentration