Lipids contain ______ tails that make them hydrophobic.

Lipids contain ______ tails that make them hydrophobic.

• A. Short hydrocarbon tails that make them hydrophobic
• B. Long hydrocarbon tails that make them hydrophobic
• C. Long hydrocarbon tails that make them hydrophilic
• D. No hydrocarbon tails and they are polar

Answer: (B)

Lipids owe their hydrophobic character to long hydrocarbon tails. These tails are nonpolar, so they interact poorly with water and tend to avoid it, causing lipid molecules to cluster and form nonpolar environments. The greater the length of these carbon chains, the larger the nonpolar surface area and the stronger the tendency to be water-insoluble, which is why they are classified as hydrophobic. In membranes, the tails tuck away from water while the polar head groups meet the aqueous surroundings, reinforcing this behavior. Statements suggesting hydrophilicity or the absence of hydrocarbon tails don’t fit because the hydrophobic nature of lipids comes from these long, nonpolar carbon chains.

Lipids owe their hydrophobic character to long hydrocarbon tails. These tails are nonpolar, so they interact poorly with water and tend to avoid it, causing lipid molecules to cluster and form nonpolar environments. The greater the length of these carbon chains, the larger the nonpolar surface area and the stronger the tendency to be water-insoluble, which is why they are classified as hydrophobic. In membranes, the tails tuck away from water while the polar head groups meet the aqueous surroundings, reinforcing this behavior. Statements suggesting hydrophilicity or the absence of hydrocarbon tails don’t fit because the hydrophobic nature of lipids comes from these long, nonpolar carbon chains.