Which gas do green plants release during photosynthesis?
AnswerOxygen
Plants use light, water and carbon dioxide to make sugar, releasing oxygen as a by-product.
Nature · Facts & stats
Green facts & stats
7 fact-checked facts about the color green in nature and green living, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
Earth Day is celebrated each year on which date?
AnswerApril 22
Earth Day events around the world take place on April 22.
Going deeper
Why do many green leaves turn yellow and orange in autumn?
AnswerGreen chlorophyll breaks down, revealing yellow and orange pigments
Carotenoid pigments are in the leaf all along but are masked by chlorophyll until it breaks down.
Emerald is a green variety of which mineral?
AnswerBeryl
Traces of chromium or vanadium give beryl its green color, making it emerald.
Why does old copper, like the Statue of Liberty, turn green?
AnswerCopper reacts with air and moisture to form a patina
Over years, copper forms a green layer of copper compounds that protects the metal underneath.
Expert level
In the RGB color model of light, which color is the complement of green?
AnswerMagenta
Magenta is made of red and blue light, the two primaries missing from green; together they make white.
The green sea turtle is named for the color of what?
AnswerIts body fat
Its shell is usually brown or olive; the name comes from greenish fat, colored by its diet of seagrass and algae.
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