Why are tomatoes red ?

Tomatoes are triggered to turn red by a chemical called ethylene. Ethylene is odorless, tasteless, and invisible to the naked (human) eye.

Explanation:

As the tomato ripens, its color starts to change from green to yellow and then eventually to red. This is due to the breakdown of chlorophyll, which in turn synthesizes a red carotenoid (another pigment group), lycopene. When ripe, the carotenoid can easily be seen as the dominant color of the tomato, red

Explanation:

in biology you'll learn more about this

the transfer of energy between two molecules spaced just nanometers apart plays a key role in many technologies, including photovoltaics, quantum information systems, lighting, and sensors, as well as in biophysics to measure nanometer distances and in photosynthesis. but an open question in this area is what effect, if any, the surrounding photonic environment has on this nanoscale energy transfer. by designing and performing a carefully controlled experiment to answer this question, scientists have settled the debate and found clues to improving the efficiency of many of the technologies that rely on this process.

explanation:

sorry, but you do not have posted the diagram.