Key Takeaways

KEY TAKEAWAYS

• There are certain qualities of living things that separate them from nonliving things.

• There is a hierarchy of life that starts with subatomic particles as the smallest part and that ends with the biosphere, which represents all ecosystems put together.

• Life on earth is carbon-based so that living things (and many nonliving things) are made with this atom.

• There are four major organic macromolecules, such as proteins, carbohydrates, lipids, and nucleic acids.

• Water is essential for life and has molecular characteristics that make it an excellent solvent and temperature-regulator. It also participates in the pH of solutions that is strictly regulated in living systems for the purpose of enzymes and enzymatic reactions.