Question

select the true statements. carbon dioxide, a small nonpolar molecule, can freely pass through the lipid bilayer. positively charged potassium ions can freely pass through the lipid bilayer. the inner core of the lipid bilayer repels polar molecules like water. the outer parts of the lipid bilayer repel polar molecules like water.

Explanation:

• Carbon dioxide, a small nonpolar molecule, can freely pass through the lipid bilayer: The lipid bilayer has a non - polar interior. Non - polar molecules like \(CO_2\) can dissolve in the non - polar region (due to the "like dissolves like" principle) and pass through the bilayer by simple diffusion.
• Positively charged potassium ions can freely pass through the lipid bilayer: This is false. The lipid bilayer's non - polar interior repels charged ions. Potassium ions (\(K^+\)) require ion channels (such as potassium channels) to pass through the membrane.
• The inner core of the lipid bilayer repels polar molecules like water: The inner core of the lipid bilayer is composed of non - polar fatty acid tails. Polar molecules (which have a dipole moment) are repelled by the non - polar environment (because non - polar and polar substances do not mix well, based on intermolecular force differences).
• The outer parts of the lipid bilayer repel polar molecules like water: This is false. The outer parts of the lipid bilayer are composed of polar heads (which have a charge or partial charge distribution). Polar molecules like water are attracted to the polar heads (due to electrostatic interactions and hydrogen bonding in the case of water).

Answer:

• Carbon dioxide, a small nonpolar molecule, can freely pass through the lipid bilayer.
• The inner core of the lipid bilayer repels polar molecules like water.