The human female grows tissue along the lining of her uterus in preparation for her falling pregnant. When she conceives, the baby attaches itself to the lining of the uterus via a placenta and umbilical cord and they provide the baby with nutrients and oxygen to grow. Approximately every 28 days a woman releases an egg to be fertilised by the male. If the egg is not fertilised within approximately 48 hours of being released, the tissue lining that has grown begins to break down. It breaks down into blood and is evacuated from the body via a period.
The starting AND ending of your periods. :)
rows. the vertical columns are called periods
7 periods
the periods are the rows
No - only mammals have periods.
periods, they are periods
they dont have periods.
Periods have same shells. There are 7 periods in periodic table.
The main dinosaur periods were the Triassic, Jurassic and Cretaceous periods. they were in the mesozoic era. there were other periods before dinosaurs like the carboniferous.
The horizontal rows are known as periods.
there are 7 periods in the periodic table118
Yes Vampires have periods. Even though they are dead creatures they do have periods. It may come as a shock but all vampired have periods even males.