دانلود رایگان کتاب Free Download of : Medical Biochemistry
Water makes up about 70% of a typical cell by weight. It is one of two solvents in which most of biochemistry occurs, the second being the lipids of membranes. Water is a very unusual substance and plays a central role in defining life as we know it. Its large dipole moment means that it is a highly polarliquid (at 37°C) and thus serves as an excellent solvent for other polar (and hydrophilic) molecules. Apolar molecules are not easily dissolved in water and are referred to as
hydrophobic. Hydrophobic molecules are excluded from an aqueous environment because they cannot interact well with water and therefore lead to a structuring of water in their vicinity (an unfavorable process). Since hydrophobes generally mix well, they separate to minimize their interface with water and form a second distinct environment – the greasy, oily environment of lipids (lipophilic).