The 11 organ systems of the body are the integumentary, muscular, skeletal, nervous, circulatory, lymphatic, respiratory, endocrine, urinary/excretory, reproductive and digestive. Although each of your 11 organ systems has a unique function, each organ system also depends, directly or indirectly, on all the others.
If you’re talking about scientific phases you will see 1. precipitation(the snow falling) 2. evaporation(water turning into vapor) 3.melting(snow turning the water)