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Why does menstruation occur?

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Question

 Why does menstruation occur?

Answer in Brief
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Solution

Menstruation is a process in which blood and mucous flow out every month through the vagina. This process occurs every month because one egg is released from the ovary every month and at the same time, the uterus (womb) prepares itself to receive the fertilised egg. Thus, the inner lining of the uterus gets thickened and is supplied with blood to nourish the embryo. If the egg does not get fertilised, then the lining of the uterus breaks down slowly and gets released in the form of blood and mucous from the vagina. It lasts for three to five days.

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Chapter 7: How do Organisms Reproduce? - EXERCISE [Page 127]

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NCERT Science [English] Class 10
Chapter 7 How do Organisms Reproduce?
EXERCISE | Q 6. | Page 127

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