A banana is an edible fruit produced by several kinds of large herbaceous flowering plants in the genus Musa. The fruit is variable in size, colour and firmness, but is usually elongated and curved, with soft flesh rich in starch covered with a rind which may be green, yellow, red, purple, or brown when ripe. The fruits grow in clusters hanging from the top of the plant. Almost all modern edible parthenocarpic (seedless) bananas come from two wild species – Musa acuminata and Musa balbisiana. Fruits of wild-type bananas have numerous large, hard seeds whereas in cultivated varieties, the seeds are diminished nearly to non-existence; their remnants are tiny black specks in the interior of the fruit. Currently India is the world leader in banana production
Export bananas are picked green, and ripen in special rooms upon arrival in the destination country. These rooms are air-tight and filled with ethylene gas to induce ripening. The vivid yellow color normally associated with supermarket bananas is in fact a side effect of the artificial ripening process. "Tree-ripened" bananas have a greenish-yellow appearance which changes to a brownish-yellow as they ripen further.
Fascinatingly; Bananas are naturally slightly radioactive, more so than most other fruits, because of their potassium content and the small amounts of the isotope potassium-40 found in naturally occurring potassium. The banana equivalent dose of radiation is sometimes used in nuclear communication to compare radiation levels and exposures.