Question

Which molecule in each pair that is more likely to diffuse through the lipid bilayer?

1) amino acids or benzene
2) Cl⁻ or ethanol
3) glycerol or RNA
4) H₂O or O₂
5) adenosine or ATP

Answer 1

Small, nonpolar molecules are more likely to diffuse through the lipid bilayer. Amino acids, Cl⁻, RNA, ATP, and O₂ are less likely to diffuse, while benzene, ethanol, glycerol, H₂O, and adenosine are more likely to diffuse.

Step-by-step explanation:

Diffusion is the process by which molecules move from an area of high concentration to an area of low concentration. In the context of the lipid bilayer, small, nonpolar molecules are more likely to diffuse through.

1. Amino acids are polar molecules and are repelled by the hydrophobic tails of the phospholipid bilayer. On the other hand, benzene is a nonpolar molecule and can easily pass through the lipid bilayer.
3. Cl⁻ is an ion and will have difficulty crossing the lipid bilayer. Ethanol, being a small, nonpolar molecule, is more likely to diffuse through.
5. Glycerol is a small, nonpolar molecule and is likely to diffuse through the lipid bilayer. RNA is a large, polar molecule and will have difficulty crossing the bilayer.
7. H₂O is a small, polar molecule that can cross the lipid bilayer. O₂ is a small, nonpolar molecule and is more likely to diffuse through.
9. Adenosine is a small, nonpolar molecule and can easily diffuse through the lipid bilayer. ATP is a larger, polar molecule and will struggle to cross the bilayer.