Membrane Permeability Flashcards
What does the term Permeability mean?
It means that the cell permits passage of substances through it.
What does Selective Permeability mean?
This means that the cell allows certain substances to exit or enter.
What molecules can freely pass through the lipid bilayer?
This includes non-polar molecules such as Oxogen, Carbon dioxide and Steroids moderately permeable to small, uncharged polar molecules such as water and Urea (a waste product).
What are Transmembrane Proteins?
These are proteins that are embedded in the plasma membrane that act as channels and carriers for a variety of molecules and gives the cell permeability to substances that cant freely cross the lipid bilayer.
What is a Concentration Gradient?
This is the difference in the concentration of a chemical from one place to another, such as from the inside to the outside of the plasma membrane.
What is a Electrical Gradient?
This is a difference in electrical charges between two regions. it occurs across the membrane, this charge difference is called membrane Potential.
What are the Concentration and Electrical Gradient used for?
They are used for helping to move substances across the plasma membrane from high to low “down its concentration gradient” to help maintain equilibrium.
