Movement Of Ions & Molecules Flashcards
What does the cell membrane being fluid and self-healing allow?
Cell division
Endo/exocytosis and budding
What causes the kink in a fatty acid chain?
Cis double bond
What is the charge on choline?
Positive
What is the charge on the phosphate group of a phospholipid?
Negative
What kind of molecules can pass directly through the phospholipid bilayer?
Hydrophobic
Small, uncharged polar
What kind of molecules cannot pass directly through the phospholipid bilayer?
Large, uncharged polar
Ions
Give an example of a hydrophobic molecule that can directly pass through the phospholipid bilayer
Oxygen
Nitrogen
Benzene
Give an example of a small/uncharged/polar molecule that can directly pass through the phospholipid bilayer
Water
Urea
Glycerol
Carbon dioxide
Give an example of a large/uncharged/non-polar molecule that cannot directly pass through the phospholipid bilayer
Glucose
Sucrose
How many of each ion does the sodium-potassium pump transport in/out?
3Na+ out for every 2K+ in
What evidence is there for the sodium-potassium pump? (3)
Tracer studies with radioactive isotopes in giant squid axons/red ghost cells (24Na, 42K)
Na+ and ATP must be inside and K+ must be outside for the pump to function
Metabolic poisons (cyanide + ouabain) block oxidative phosphorylation and block the pump therefore ATP must be involved
What is symport?
Two (types of) molecules moving in the same direction during active transport
What is antiport?
Two (types of) molecules moving in different directions during active transport
What is secondary active transport?
Movement down a gradient (formed by primary active transport) facilitated by protein carriers
What are the concentrations of sodium ions inside and outside cells?
10mM inside
140mM outside
