Alive Today

: Organisms react to their environment, such as a plant growing toward light or an animal fleeing from a loud noise.

: Living things increase in size or complexity over time throughout their lifespan. : Organisms react to their environment, such as

: The capacity to produce offspring, either sexually or asexually, to ensure the continuation of the species. : All living things are composed of one

: All living things are composed of one or more cells, which contain DNA and organized structures. Organisms either produce their own food (like plants)

In science, "alive" refers to organisms that perform specific vital functions. While there is no single perfect definition, biologists generally agree on seven key characteristics that distinguish living things from non-living matter:

: Life requires energy to function. Organisms either produce their own food (like plants) or consume others to fuel biological processes.