When water evaporates it carries heat energy with it, this cools the remaining water. The seas resist freezing and boiling. Earth experiences a temperature range that allows most of the water to remain as liquid or solid. Unequal heating of our planet by our sun moves water vapor over the planet distributing energy. Living creatures must acquire energy and store it.
All life is composed of a basic unit- the cell.
Sequences of the DNA called genes direct a complicated series of chemical pathways within the cell. These chemical pathways permit life. A cell may eat, move, respond to the environment, grow and make copies of itself. The goal is to better understand our life. Understanding leads to purpose and self-guidance.