As defined, Biology is the science of living substances (jīvadravayas). The field of Jaina Biology differentiate the living from non-living by using the word jīvasttikāya (organism) [12] to refer to any living things, plants or animals, just as modern biology does, so it is relatively easy to see that a man. [13] A Sāla tree, [14] a creeper [15] and a earth worm [16] are living, where as a piece of matter (pudgala) e.g. wood, stones etc. are not so. [17] Some materialists maintain the view that elements are non-conscious (acetana). Consciousness is not the character of element or the result of elements, while soul is the name of that reality (tattva) with consciousness (soul) is related as character of result. [18] According to modern biology "protoplasm is the actual living material of all plants and animals." This is not a single substance but varies considerably from organism to organism, among the various parts of a single animal or plant and from one time to another with a single organ or part of animals or plant. There are many kinds of protoplasm, but they share certain fundamental physical and chemical characteristics. [19] The protoplasm of the human body and of all plants and animals exists in discrete portions known as cells. These are microscopic units of structure of the body, each of them is an independent, functional unit, and the processes of the body are the sum of the co-ordinated functions of its cells. These cellular units vary considerably in size, shape and function. Some of the smallest animals have bodies made of single cell, other such as, a man or an oak tree are made of countless billion of cells fitted together. [20]
According to modern biology "The structural and functional unit of both plants and animals is the cell." The simplest bit of living matter that can exist independently. The cell itself has specific organization, for each type of cell has a characteristics size and shape, it has a plasma membrane which separates the living substance from the surrounding, and it contains a nucleus, a specialized part of the cell separated from the rest by a nuclear membrane. The nucleus plays a major role in controlling and regulating the activities of the cell. The bodies of the higher animals and plants are organized in series of increasingly complex levels. Cells are organized into tissues, tissues into organs and organs into organ system.[21]