500科同利

FEATURES

Japanese

Print

Why are leaves green?

March 17, 2023

Simple questions and 500科同利
An introduction to academia starting with “Why?”

After making a list of questions which would pique anyone’s interest, we asked faculty members on campus who might be knowledgeable in these areas to answer them from the perspective of their respective expertise. Let’s take a look into the world of research through questions that you feel you know something about, but cannot answer definitively when actually asked.

Q16. Why are leaves green?

Plants use photosynthesis to produce sugars and other organic compounds out of light energy, carbon dioxide and water. Wouldn’t plants absorb sunlight more efficiently if their leaves were black? Why are they green?
A. Because green light is escaping from them.
Answered by Ichiro Terashima
Professor,
Visible light spectrum: Wavelength of 400–700 nm (nanometers)
Visible light is light in the range that can be seen by the human eye. The colors in the visible light spectrum, in increasing order of wavelength, are violet, indigo, blue, green, yellow, orange and red.

Rubisco: a large and inefficient enzyme

Measuring photosynthesis using a dual light source irradiation device

When we see the color black, it means that all light is being absorbed, so it’s true that black leaves would be ideal from the standpoint of efficiency of light absorption. But