A cell is the smallest LIVING unit in a body. An atom is the smallest "nonliving" unit.
Answer:In biology, an organ are when tissues come together that structurally form a functional unit specialized to perform a particular function. Your heart is a example of organs
Explanation:
Biogeography is the study of geographical distribution of fossils, various species (plants and animals) and ecosystems throughout geological time and space
Http://highered.mheducation.com/sites/007246268x/student_view0/chapter13/
Explanation: The water cycle is when water changes state of matter starting at water than evaporation ( water rising in the air) to condensation ( the formation of a cloud) to precipitation (when it rains) and than repeat. hope this helped.