Questions: Which one of the following molecules would be most likely to travel by facilitated diffusion? a tiny inorganic molecule a large, charged molecule a molecule of oxygen

The answer is the second one: a large, charged molecule.

Explanation for each option:

1. A tiny inorganic molecule: Tiny inorganic molecules, such as water or small ions, can often pass through the cell membrane via simple diffusion or through specific ion channels without the need for facilitated diffusion. Therefore, this option is less likely to require facilitated diffusion.

2. A large, charged molecule: Large, charged molecules cannot easily pass through the lipid bilayer of the cell membrane due to their size and charge. These molecules typically require the assistance of protein channels or carriers to move across the membrane, making facilitated diffusion the most likely method for their transport.

3. A molecule of oxygen: Oxygen is a small, nonpolar molecule that can easily diffuse through the lipid bilayer of the cell membrane without the need for protein channels. Therefore, it is less likely to travel by facilitated diffusion.

In summary, facilitated diffusion is most likely used by large, charged molecules to cross the cell membrane.