Why does menstruation occur?
Solution and Explanation
When in human female, egg is not fertilized, it lives for about one day. Since the ovary releases one egg every month, the uterus also prepares itself every month to receive a fertilized egg. Thus, its lining becomes thick and spongy. This would be required for nourishing the embryo if had fertilized.
However, this lining is not required any longer if fertilisation has not occured. So, the lining slowly breaks and comes out through the vagina as blood and mucous.
This cycle takes roughly every month and is known as menstruation.
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Concepts Used:
Sexual Reproduction
Sexual reproduction takes place in both plants and animals. In sexual reproduction, genetically diverse organisms or sphinx are built this happens when two individuals of unique sex are combined.
The offspring built by sexual reproduction are genetically diverse in nature and can embrace themselves in accordance with the climate and other adaptable conditions many multicellular organisms practice sexual reproduction.
There are four types of sexual reproduction:
- Allogamy
- Internal fertilization
- External fertilization
- Autogamy