I'm pretty sure it's carbohydrates
Answer:
Due to their hole size.
Explanation:
Some molecules can pass directly through the phospholipid bilayer because of their small size which can easily pass through the small holes of phospholipid bilayer, while those that are too large or too charged need to pass through a membrane protein because membrane protein has a large holes through which large molecules can easily pass through the semi-permeable membrane of the cell by active or passive transport.
What are the answer choices ?
