1. On the chili peppers:
- When chili comes in contact with our tongues, capsaicin triggers pain receptors in the mouth that indicate heat, thus sending messages to our brains that something hot has been eaten.
- Source: http://suite101.com/article/why-are-chili-peppers-spicy-a131849
2. On Chromium:
- It has a chemical symbol of Cr and atomic number of 24. It became high demand in the market when scientists discovered that it has properties that make it high corrosion resistance and hardness.
- Source: http://en.wikipedia.org/wiki/Chromium#Chromium.28III.29
3. On ethylene:
- It is an organic compound that is used as a natural plant hormone that is used to quicken the ripening of fruits.
- Source: http://en.wikipedia.org/wiki/Ethylene
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