Characteristics of Life Characteristic One: Organisms are made of units called cells Organisms can be unicellular (made of one cell) or multicellular (made of many cells)

Characteristics of Life Characteristic Two: Reproduction All living things reproduce themselves Reproduction can be asexual (one parent) or sexual (two parents)

Characteristics of Life Characteristic Three: Based on genetic code Organisms have DNA or RNA that is a blueprint for creating them DNA or RNA is passed on to offspring

Characteristics of Life Characteristic Four: Growth and Development All organisms grow, either by enlarging their one cell or dividing their cells millions of times

Characteristics of Life Characteristic Five: Need for materials and energy Organisms create and break down molecules to fuel their chemical reactions The four molecules we use are proteins, fats, carbohydrates, and nucleic acids

Characteristics of Life Characteristic Six: Response to environment Organisms detect and react to stimuli in their environment Stimuli are internal (like your blood sugar) or external (like plants reacting to sunlight)

Characteristics of Life Characteristic Seven: Internal balance Organisms keep their internal environment stable through homeostasis Ex: Body temperature When you get too hot, you sweat to cool your skin When you get too cold, you shiver to warm your body

Characteristics of Life Characteristic Eight: Evolution Populations of organisms change over time in response to their environment Changes are only significant over long periods of time