Five characteristics of living things, which are comprised of one or more cells, include the ability to grow, adapt and reproduce, along with responsiveness to stimuli and metabolic processes necessary for survival. The term "living things" encompasses animals, plants and simple organisms, such as amoeba, fungi, viruses and bacteria. Scientifically, living things are categorized into animal and plant kingdoms, depending on their similarities.
The cell is the basic unit of living things, and its chemical processes and components have fundamental similarities in all living organisms. Cells contain genes, which determine the unique characteristics of living things. In addition, living things require energy to survive. Plants use the sun to make their food, but animals depend on food from the environment. Living things develop or grow through organized changes in shape and body functions.
Growth also involves the process of repairing damaged cells and tissues. Responsiveness to the environment allows living things to adapt to change and survive. The ability to move is limited in some living things, such as plants. Most living things also work and depend on other life forms for survival. For example most animals depend on other animals and plants for nutrients. They also compete for resources, such as food, moisture, sunlight and space. When living things die, bacteria and fungi act upon their cells and tissues, causing decay and release of nutrients to the soil for plants to absorb and utilize.