Final answer:
Cryoprotectants are absorbed by tissue cells through the process called osmosis, which is the movement of water across a semipermeable membrane to balance solute concentrations.
Step-by-step explanation:
Osmosis is a passive transport mechanism by which water molecules move across a semipermeable membrane from a region of higher water concentration to one of lower water concentration. This equilibrium-seeking process occurs until the concentration of water is balanced on both sides of the membrane, making it crucial for maintaining cellular integrity.
A cryoprotectant is a substance that can protect biological tissue from freezing damage and is absorbed by tissue cells through osmosis. For example, when cells are placed in a solution with a cryoprotectant, water within the cells moves out to balance the concentration of the cryoprotectant inside and outside the cell, thereby allowing the cryoprotectant to enter the cells by osmosis.