Why is it important to control the variables you are not testing ?

Which of the following is the best definition for the process of photosynthesis? a.) plants digest sugars to make energy. b.) plants use oxygen and glucose to make carbon dioxide. c.) plants use sunlight and carbon dioxide to make sugars. d.) plants use sunlight to make chlorophyll and chloroplasts.

Mrna decodes information from the original dna master plan to build proteins in the during the process of ribosomes.

What environmental cues and landmarks do the geese use to determine the timing and direction of their migration over the mountains? how do they find their way?