A student set up an experiment to show the effect of light color on photosynthesis in Elodea plants. She filled three test tubes with distilled water and placed a piece of Elodea in each of the tubes. She added a drop of phenol red, which turns red in a basic solution and yellow in an acidic solution. She blew in each tube to add carbon dioxide, which caused the distilled water to become more acidic so the phenol red turned yellow. She exposed Tube A to white light, Tube B to green light, and Tube C was wrapped in aluminum foil. Which of the tubes should she expect to turn red the fastest?

From the setup of the experiment to show the effect of light color on photosynthesis in Elodea plants, the solution in Tube A should turn red the fastest.

White light is essentially a mixture of all light colors. Hence, the Elodea plant in Tube A will absorb the most effective light color from the white light for its photosynthesis, utilizing the carbon dioxide in the tube's solution faster and making it turn red.

Green light is generally considered to be the least efficient of all light colors when it comes to photosynthesis. Hence, the rate of consumption of carbon dioxide from the tube with green (Tube B) light would be slow.

There will not be any photosynthesis in Tube C because there is no light for the process. the aluminum foil would have blocked any form of light that could get to the plant in the tube.

More on light colors and photosynthesis can be found here: link?

Tube A will turn red the fastest.

Explanation:

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.