This document defines key terms related to ecosystems and photosynthesis. It explains that spotted salamanders and pea aphids can perform photosynthesis like plants due to symbiotic relationships with algae. Living things in an ecosystem range from microscopic organisms to plants and animals, all interacting and dependent on both living and nonliving components. Photosynthesis plays an important role in the oxygen and mineral cycling within ecosystems. The environment supports all life and is influenced by human behavior.