Final answer:
Option A is correct option. Molecules that can diffuse through the lipid bilayer include those that are small, uncharged, and hydrophobic. Benzene, ethanol, glycerol, oxygen, and adenosine are the molecules more likely to diffuse across the lipid bilayer in each pair provided, respectively.
Step-by-step explanation:
The student's question is about identifying which molecules are more likely to diffuse through the lipid bilayer of a cell membrane. This involves understanding the properties of molecules in relation to the characteristics of the lipid bilayer. The ability of a molecule to diffuse through the lipid bilayer is influenced by its size, charge, and polarity.
For each pair:
- a) Amino acids or benzene: Benzene is more likely to diffuse through the lipid bilayer because it is hydrophobic and nonpolar, unlike amino acids which are generally polar and sometimes charged.
- b) Cl⁻ or ethanol: Ethanol is more likely to diffuse through the lipid bilayer due to its relatively small size and low polarity compared to the highly charged Cl⁻ ion.
- c) Glycerol or RNA: Glycerol is more likely to diffuse through the lipid bilayer because it is smaller and less polar than the large, highly polar RNA molecule.
- d) H₂O or O₂: O₂ is more likely to diffuse because it is nonpolar and has a very small size, whereas H₂O is polar, albeit it can still diffuse in very small amounts).
- e) Adenosine or ATP: Adenosine is more likely to diffuse through the lipid bilayer because it is less polar and has a smaller molecular size than ATP, which is a larger molecule with charged phosphate groups.
The lipid bilayer is primarily composed of hydrophobic tails and hydrophilic heads, allowing for the passage of small, uncharged, and hydrophobic molecules via simple diffusion.