Chapter 8: Biolgical Membranes Flashcards
What’s plasma membrane made of?
- Phospholipids
Others ones: - Sphingolipids
Ceramide
Sphingomyelin
Cerebroside
Ganglioside - Cholesterol
- Waxes
What’s plasma membrane like?
The outer layer has hydrophilic (polar) and inside has hydrophobic (non polar) properties
What are integral protein?
Proteins associated with internal portion of lipid bilayer
What are transmembrane proteins?
Integral proteins that pass all the way through the bilayer
What is an example of transmembrane protein?
Aquaporins or water channels that let molecules pass in and out of the cell
Embedded proteins
Located in inner (cytoplasmic) and outer (extracellular) surface of plasma membrane
What does cytoplasmic farnesyl (eg of embedded protein) makes?
It is involved in making terpenes, terpenoids, and sterols on interior of plasma membrane
What proteins can be easily removed or attached to the plasma membrane?
Membrane associated or peripheral proteins which are bound to lipid bilayer through electrostatic interactions
What solutes can pass through plasma membrane?
- Water passes through easily because of aquaporins and transmembrane
- Small nonpolar molecules pass through due to interaction with inner hydrophobic portion
- Large or complex molecules cannot go through due to inside hydrophobic region
What is passive diffusion?
Molecules moving from higher concentration to lower concentration
What’s facilitated diffusion?
It occurs when molecules can’t normally pass through membrane
What does active transport use to move things across?
ATP or another energy molecule
What’s second or coupled transport?
When we use electrochemical gradient instead of ATP hydrolysis
What’s it called when particles flow in same direction?
Symport
What’s it called when particles flow in opposite directions?
Antiport
