Answer:
A period happens because of changes in hormones in the frame. Hormones are chemical messengers. The ovaries launch the lady hormones estrogen and progesterone . those hormones motive the liner of the uterus (or womb) to build up. The constructed-up lining is prepared for a fertilized egg to connect to and begin developing. If there is no fertilized egg, the liner breaks down and bleeds. Then the identical manner occurs all once more.
It normally takes about a month for the liner to build up, then smash down. this is why a lot of ladies and women get their periods round once a month.
Source:
https://kidshealth.org/en/teens/menstruation.html
https://www.plannedparenthood.org/learn/health-and-wellness/menstruation
thectgod ig follow
Answer:
I'm pretty sure the answer is natural selection.
Explanation:
Natural selection acts on phenotypic variations in populations.
