Question

Question was provided via image upload.

Explanation:

To solve this, we recall the concept of a semipermeable membrane. A semipermeable membrane (1) allows certain molecules through. Water and small molecules (2) can pass, while solute particles (3) (larger or not small enough) cannot.

1. The first blank (1) is for the structure that controls passage, which is "semipermeable membrane".
2. The second blank (2) is for what can pass, typically small molecules (along with water).
3. The third blank (3) is for what cannot pass, which are solute particles (since they are larger or not able to cross the semipermeable membrane easily).

Answer:

1. semipermeable membrane
2. small molecules
3. solute particles