Final answer:
Tonicity refers to the concentration of solutes and solvent on both sides of a cell membrane. Hypotonic solutions cause cells to swell, isotonic solutions have balanced concentrations, and hypertonic solutions cause cells to shrink. Enema retention can be hypo, iso, or hyper-tonic, depending on the concentration of solutes compared to body fluids.
Step-by-step explanation:
Tonicity refers to the relative concentration of solutes and solvent on both sides of a cell membrane. In a hypotonic environment, water enters a cell, causing it to swell. In an isotonic condition, solute and solvent concentrations are equal, resulting in no net movement of water. In a hypertonic solution, water leaves the cell, causing it to shrink. This can compromise cell function and even lead to cell destruction.
Enema retention can be categorized into hypo, iso, and hyper-tonic solutions. Hypotonic enemas have a lower concentration of solute compared to body fluids, causing water to enter the colon and soften the stool. Isotonic enemas have the same concentration of solute as body fluids, resulting in minimal water exchange. Hypertonic enemas have a higher concentration of solute than body fluids, causing water to leave the colon and promote stool evacuation.