Explain how an atom that was once part of the rat's body could become part of a bird's body.

Consider the last statement in the prompt: "people take such environmental factors into account in their choices when deciding where to live." do all people have a choice as to where they live? what factor plays a key role in this decision and may therefore play a large role in determining quality of life?

When does the circulatory system work with the respiratory system? a. during blood cell formation b. during cellular respiration c. during intestinal digestion d. during a viral infection

This group of organisms perform the process of ammonifcation. a. herbivores b. decomposers c. carnivores c. plants