All organisms are made up of cells, have different levels of organization, use energy, respond to and adapt to their environments, grow and reproduce. If something does not exhibit each of these characteristics, it is technically not living.
The cell is the basic unit of life, and each living thing consists of one or more cells. An organism shows levels of organization within itself, whether molecular or cellular.
Organisms all need some form of energy to carry on the basic function of life. They also use energy to grow and develop. Once mature, an organism can engage in reproduction to pass its genes on to the next generation. Living things respond to their environments through actions such as moving away from danger.