Curiosity

Cells contain molecules that are made up of even smaller components called atoms.

http://www.dummies.com/education/science/building-the-body-from-atoms-to-organs/

What are atoms?

What are atoms?

Atoms are the basic building blocks of matter that make up everyday objects. A desk, the air, even you are made up of atoms!

Atoms are the basic units of matter and the defining structure of elements. The term "atom" comes from the Greek word for indivisible, because it was once thought that atoms were the smallest things in the universe and could not be divided. We now know that atoms are made up of three particles: protons, neutrons and electrons — which are composed of even smaller particles such as quarks.

https://education.jlab.org/atomtour/
https://www.livescience.com/37206-atom-definition.html

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