Here are some quick tips on how to distinguish classic crystal from plain glass. 1  Hold up a glass to the light. 2  If the glass acts as a prism and you see a rainbow you are holding crystal. 3  If not, it is just plain glass. 4  When struck, crystal produces a musical ring. 5  Glass does not.
Hormonal control of menstrual cycle. The ovarian hormones circulate in the blood and are excreted in modified forms in the urine. Estimation of the urinary output by chemical methods gives an indication of the blood levels and of the total production of these substances.
A womanâs menstrual cycle affects her brain in a number of ways, for better or for worse. Estrogen, progesterone, and testosterone fluctuate during a womanâs menstrual cycle. The hippocampus, hypothalamus, and the amygdala tend to be affected the most by the estrogen-progesterone surges and drops. The surges of these hormones can influence a womanâs mood, self-esteem, and how she connects to others.