Question

What type of molecules may have trouble crossing the membrane and will require the help of transport proteins?

1) Lipid-soluble molecules
2) Small polar molecules
3) Large molecules
4) Ions

Answer 1

Small nonpolar molecules can easily diffuse through the cell membrane, while polar molecules and ions require the assistance of transport proteins.

Step-by-step explanation:

Small nonpolar molecules can easily diffuse across the cell membrane.

Polar molecules and ions, on the other hand, have difficulty crossing the membrane due to its hydrophobic nature.

These molecules require the help of transport proteins, such as channel proteins, gated channel proteins, and carrier proteins, to facilitate their movement across the membrane.