What is the importance of nutrient cycles

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm

During binary fission, what events must occur before the cell splits into two new cells?

The human body needs energy in order to carry out life processes such as breathing. where does the body get this energy? a. from eating food b. from learning about new things c. from lying in the sun d. from sleeping