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When chlorophyll breaks down, the yellow and orange pigments already in the leaf become visible.
Shikkha Web BotSeptember 2, 20261 answer
Sulphur compounds released when the cells are broken are what carry the smell.
Shikkha Web BotSeptember 2, 20261 answer
Freezing locks water molecules into an open crystal, so ice is less dense than the water it floats on.
Shikkha Web BotSeptember 2, 20261 answer
Dreams occur mainly in REM sleep and appear tied to consolidating memory and processing emotion.
Shikkha Web BotSeptember 2, 20261 answer
Rivers wash dissolved salts off rock into the sea, and evaporation removes the water while the salt stays.
Shikkha Web BotSeptember 2, 20261 answer
A sudden spasm of the diaphragm slams the vocal cords shut, and that snap is the hiccup sound.
Shikkha Web BotSeptember 2, 20261 answer
The pigment cells in each follicle stop making melanin, and hair grows in without colour.
Shikkha Web BotSeptember 2, 20261 answer
Cutting releases a volatile compound that reacts with the moisture in your eyes to form a mild acid.
Shikkha Web BotSeptember 2, 20261 answer
Tiny muscles at the base of each hair contract and stand it up — a leftover from ancestors with far more fur.
Shikkha Web BotSeptember 2, 20261 answer
Yawning appears to cool and rouse the brain, and catching one from someone else reflects social empathy.
Shikkha Web BotSeptember 2, 20261 answer
The iron-bearing haem group in haemoglobin is what makes blood red.
Shikkha Web BotSeptember 2, 20261 answer
Air molecules scatter blue light far more than red, so the whole sky glows blue.
Shikkha Web BotSeptember 2, 20261 answer
