All organisms get the energy they need to regenerate atp from

What is the answer for the complicated molecules that make up living things usually contain carbon. why is carbon so important in these molecules?

Why do leaves change color in the fall? green pigments break down and no longer mask the color of chlorophyll. chlorophyll breaks down and no longer masks the colors of other pigments. red- and yellow-colored pigments grow and mask green-colored chlorophyll. green-colored chlorophyll breaks down and turns red and yellow.

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?