Phospholipids are large organic molecules with a ________, polar phosphate head connected to ________, nonpolar fatty acid tails. How do these molecules arrange themselves to form a mostly impermeable barrier between a liposome and its environment?
a. hydrophilic; hydrophobic; They line up hydrophilic head to hydrophilic head with the tails all facing outward from the center line of the membrane.
b. hydrophilic; hydrophobic; They line up hydrophobic tails facing each other at the center line of the membrane with the hydrophilic heads facing outward, away from the center line of the membrane.
c. hydrophobic; hydrophilic; They line up hydrophobic tails facing each other with the hydrophilic heads facing outward, away from the center line of the membrane.
d. hydrophobic; hydrophilic; They line up hydrophilic head to hydrophilic head with the tails all facing outward from the center line of the membrane.
Ans: b. hydrophilic; hydrophobic; They line up hydrophobic tails facing each other at the center line of the membrane with the hydrophilic heads facing outward, away from the center line of the membrane.
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