Question

Why does a raisin swell up in a hypotonic medium though the cells have a cell present in the?

Answer 1

Hypotonic solution is a solution in which outside solution is less concentrated than inside the cell.
Thus, when raisin is put inside the hypotonic solution like water, it will swell due to osmosis. Since amount of water is high outside the raisin than inside, thus it will move inside (higher concentration to lower concentration). This process is termed as endosmosis.