Biology / Unit 1 Bio 0034 short lesson, about 20 seconds
Scientific Theory
Captions available
The idea
A scientific theory is a broad, thoroughly tested explanation for a set of observations, repeatedly confirmed by independent evidence.
In practice
Cell theory, that all living things are made of cells, has held up against every organism examined since it was proposed.
Where people slip
In this course theory always carries this tested, confirmed sense — never the everyday sense of a hunch.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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