What Is Living?

What are living things? The difference between living and nonliving things has been a debate for a long time in the history. Thus, various characteristics have been considered since then, to differentiate them from one another. Let us look at a few of them.


Defining Factors for Living and Nonliving



When we talk about growth, we do not just consider the increase in height. Growth is usually defined by the increase in mass and number of individual organisms. Humans visibly grow up to a certain age but the cells keep on dividing and thus new cells in the body keep on replacing the old ones. Some of the nonliving things also seem to grow in size due to the accumulation of particles, for example – the growth of a mountain. Living beings grow from inside due to cell division. Thus, growth is not a defining character.


It is the process by which an organism produces an individual like its own. There exist two types of reproduction – Sexual and asexual reproduction. Most of the mammals like humans reproduce by sexual reproduction. But when we consider unicellular organisms like bacteria, growth and reproduction become ambiguous as both results from the division of the cell. Thus, reproduction again cannot be considered as a typical character in defining the living.



It comprises of all the chemical reactions going inside a living cell or body. Thus, it is a typical characteristic of living beings. Nonliving things do not show metabolism.

Cellular organization

Organisms are typically made up of cells. They also follow an organization of cells followed by tissues which again group up to form organs; which in turn again combine to form the organ system. Organ systems together form an organism. This kind of cellular organization is absent in nonliving beings.

Few examples of are nerve cell, muscles, tissue, etc.


It is a property by the virtue of which an organism reacts to an external stimulus or change in environment. It is a typical property of living organisms. They have an ability to sense any change in their environment.

However, defining living state is not easy in humans. For example, in situations like coma, a person is not dead but does not define all the living characteristics as well.

Stay tuned with Byju’s to learn more about Living and Nonliving things.

Practise This Question

Biological organisation starts with