Question: How come some things are alive also if everything is made up of atoms?

Liza Sazonova answered on 11 Nov 2020: last edited 11 Nov 2020 8:05 pm

That’s a really good question! We still don’t know what is life and how is it made. Lots of people are working on this — biologists, physicists and even philosophers.
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The “atoms” part we sort of have an idea about. You’re right, everything is made of some very simple building blocks. But there are many, many of these blocks. Simple molecules like water are only made of a handful of atoms and are certainly not alive. But living things are a lot more complicated.
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A cell is made from a bunch of stuff: cell wall, nucleus, vacuole, etc. Inside the nucleus, we have the DNA, which governs how the cell works. DNA is a molecule that consists of billions of atoms (human DNA has about 200 billion). They are very, very complicated. And that’s just one part of one cell!
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Even the simplest living creature, the trichoplax, which is just a microbe 1mm in size, is made of billions and billions of atoms.
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In science, we often face the case where we really understand the building blocks of something. But stack enough of them — and they start interacting with each other and we stop understanding it. Take chess for example: the game would be easy to figure out if there was one piece, but with a full chess board it’s completely impossible for one person to consider every outcome.
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Well, it’s hard enough for us to predict what happens when we stack a few 100-atom molecules together! On scales of living organisms, it’s completely impossible. All the different ways these atoms interact with each other give rise to weird things, and even life.