In the intro to biology video, we defined biology as the branch of science concerned with the study of living things, or organisms. That definition is pretty straightforward. However, it opens the door to …

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An introduction to cells, including the history of their discovery and the development of cell theory.

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However, at the most basic level, your body—and, in fact, all of life, as well as the nonliving world—is made up of atoms, often organized into larger structures called molecules. Atoms and molecules …

Structure and function of the plasma membrane and cytoplasm of cells. Also covers the phospholipid bilayer and microvilli.

Evidence for evolution: anatomy, molecular biology, biogeography, fossils, & direct observation.

We can define the life history of a species as its lifecycle, and in particular, the lifecycle features related to survival and reproduction 1 . Life history is shaped by natural selection and reflects how members …

Learn what an ecosystem is, how energy and matter move through ecosystems, and what makes an ecosystem stable.

Carl Linnaeus, the father of modern taxonomy, developed a system for classifying living organisms into categories like species, genus, order, class, and kingdom. This tree of life helps us understand …