First comes non-rem sleep, followed by a shorter period of rem sleep, and then the cycle starts over again
Groundwater dissolves the rock when it flows through
Melanin is a pigment found in your skin and hair cells that gives each its color. ... When sun shines on your skin, it destroys the melanin as well. But since your skin is alive, it can respond to the sun's damage. Your skin cells make more melanin and your skin becomes darker
