Changes in temperature can significantly affect the permeability of cell membranes. Cell membranes are primarily composed of lipids, proteins, and carbohydrates, with the lipids forming a bilayer structure. The fluidity and permeability of the cell membrane depend on the lipid composition and the environmental conditions, such as temperature.1. Low temperatures: At low temperatures, the lipids in the cell membrane become more tightly packed, and the membrane becomes more rigid and less fluid. This reduced fluidity can decrease the permeability of the membrane, making it more difficult for molecules and ions to pass through. In extreme cases, low temperatures can cause the membrane to undergo a phase transition from a fluid state to a gel-like state, which can lead to cell damage or death.2. High temperatures: At high temperatures, the lipids in the cell membrane become more fluid and disordered, increasing the membrane's permeability. This increased permeability can allow unwanted molecules and ions to enter or exit the cell, potentially disrupting cellular processes and leading to cell damage or death. High temperatures can also cause proteins embedded in the membrane to denature, further affecting membrane permeability and function.In summary, changes in temperature can significantly affect the permeability of cell membranes by altering the fluidity of the lipid bilayer and the structure of membrane proteins. Maintaining an optimal temperature is crucial for the proper functioning of cell membranes and overall cellular health.