LIFE SCIENCE

Detailed explanation-1: -The most important parameters that govern transmembrane diffusion are polarity and size. For example, small nonpolar gases such as O2, CO2, and N2, and small polar molecules such as ethanol cross lipid membranes rapidly.

Detailed explanation-2: -Diffusion, surface area and volume.

Detailed explanation-3: -There are two major ways that molecules can be moved across a membrane, and the distinction has to do with whether or not cell energy is used. Passive mechanisms like diffusion use no energy, while active transport requires energy to get done.

Detailed explanation-4: -The rate of diffusion in cells is affected by factors such as temperature, concentration gradient, size of the molecule, and the presence of a membrane.

Detailed explanation-5: -Three key factors influence cell membrane fluidity: temperature, cholesterol, and the kind of fatty acids in the phospholipids that form the cell membrane.