Alive

: All living things are composed of one or more cells, which contain DNA and organized structures.

: Living things increase in size or complexity over time throughout their lifespan. : All living things are composed of one

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

: The capacity to produce offspring, either sexually or asexually, to ensure the continuation of the species. either sexually or asexually

: Over generations, populations of living things change to better survive in their specific environment. 2. The Human Experience: What It Means to "Feel Alive" What Really Makes Us Feel Alive (And Why We've Forgotten)

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

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: