The first idea, the evolutionary process behind the diversity and unity of life, is presented by the evolution of HeLa cells. Cells must adapt to their ecological niche. This happens when a cell divides, genetic mutations occur, and those that make the cells better suited to their ecological niche, or petri dish, are preserved by natural selection. “When Henrietta Lacks' cells became cancerous, they also acquired the ability to survive indefinitely in a culture medium; This massive genetic transformation made them considerably different from ordinary human cells, and after four decades of evolution, they became even more different. Different strains of HeLa cells, analogous to different races of human beings, even developed in some geographically separated lineages. (discovermagazine.com). The second idea, that biological systems use free energy and molecular building blocks to grow, reproduce, and maintain dynamic homeostasis, is represented when cells reproduce. HeLa cells are considered immortal, meaning they stay alive and can grow indefinitely. This tells us that the cells are not in homeostasis because their “births” exceed their “deaths”. The reason behind this and the type of energy the cells use are not entirely known, making it difficult to completely connect HeLa cells to AP Biology's second big idea. THE