what is a membrane in biology
Membrane. Definition. noun, plural: membranes. (1) (biology) A thin layer of tissue covering a surface or lining a cavity, space or organ. (2) (biology) A cell membrane. (3) (chemistry) A thin pliable sheet of material that is permeable to substances in solution.Supplement. A biological membrane functions by protecting the surface or bodily organ.1) (biology) A thin layer of tissue covering a surface or lining a cavity, space or organ. (2) (biology) A cell membrane. (3) (chemistry) A thin pliable sheet of material that is permeable to substances in solution. Supplement. A biological membrane functions by protecting the surface or bodily organ.