If you take a close look at the world, you may notice everything is composed of smaller pieces, from ingredients in food to threads in a shirt. However, food and clothes are each more than a sum of individual parts. A room filled with spools of thread will not get you dressed in the morning; but weave the thread together, and you have something to wear! As objects are assembled, new characteristics, or emergent properties, appear.
As you study biology, you will discover how life itself emerges as smaller pieces, or molecules, combine to form cells. Atoms, the smallest units of matter, build molecules. Each atom is one of many different kinds of elements, such as oxygen or hydrogen. Similar to a child’s building blocks, atoms are assembled in many different patterns to create molecules.
Molecules may be small or large, containing a few or millions of atoms. Organic macromolecules interact to create a cell, the basic unit of life. Some cells exist as unicellular organisms, while others work together to form multicellular organisms. Inside more complex organisms, cells may form tissues, organs, and organ systems.
Emerging properties may arise by transient interactions such as individual organisms building a population. Human interaction in populations leads to the emergence of language, poetry, musical composition, and art. When populations of different species interact, communities form. Many emergent properties are the result of interactions between species in communities. For instance, a cow’s ability to digest grass depends on bacteria living in the cow’s stomach! As communities interact with the physical environment, ecosystems form. Together, the ecosystems on planet Earth form a biosphere. Without life, Earth would be unrecognizable. Without Earth’s water and minerals, life could not exist. Large scale interactions are the result of smaller scale interactions, but life on Earth is much more complex than a simple sum of interactions.
This slide show illustrates emergent properties from simple atomic interactions to complex communities.
Levels of Biological Organization
Use this activity to review the levels of biological organization.