I think it’s the first one
Your body systems work together to keep you alive. Each of these systems is made up of organs
with specific functions. The structure of these organs and the cells of which they are made make
them well suited to their function. An important function of your body systems is to supply your cells
with energy and nutrients, and to remove wastes that are produced, thats the best I
have.
The answer would be Uterine.
During a girls cycle an unfertilized egg sheds on the uterine wall. This mainly lasts for about 7 days. When a unfertilized egg reaches the unterine wall it tens to shed which makes it a cycle.
