Living things are made up of units called cells. These are organized into tissues, tissues in turn form organs and a number of organs working together comprise of an organ system.
Living things grow and develop. They take material from the environment and organize the material into its own structure.
All living things are able to respond to stimulus of the external environment. They respond to changes in light, heat, sound, chemicals, and mechanical contact. Internal stimulus arises within the organism. For example: if the level of sugar (glucose) in the blood becomes low, the body responds by triggering hunger.
Universal genetic code gives the mRNA sequences that specify the amino acids. The mRNA sequences arise from deoxyribonucleic acid or DNA, the inheritable material that determines the inheritance of the traits of every organism on earth.
All living organisms produce new organisms through a process called reproduction. There are two basic kinds of reproduction sexual and asexual reproduction.