Any of various substances that show the presence, absence, or concentration of a substance.

What evidence supports the law of conservation of energy? a) mechanical energy is converted to chemical energy during photosynthesis. b) oxygen is made from the breakdown of carbon dioxide during photosynthesis. c)energy is absorbed by chlorophyll and becomes chemical energy during photosynthesis. d)the sun gives off light energy that is absorbed by plants.

Identify the structure in organisms that do not have kidneys that is adapted to regulate water balance

Do plant cells perform cellular respiration?