The History of Earth: CELL
Life has started, but what shape did it take? What form? What is the build-block of our existence? Welcome to Part 11 of the History of Earth.
All living things are made of cells.
Humans have 30 trillion cells. Give or take. Which is a lot of cells.
But life on Earth started with organisms that consisted of just one cell. One teeny-tiny cell. All on its own.
And, even now, the vast majority of life on Earth is still single-celled.
But what is a cell?
The first thing to note is that a cell is extremely complex. There are 100 trillion atoms in a single human cell. Now, that’s a lot of atoms.
And it is perhaps easiest to think of a cell as being similar to a body.
After all, you and I are both single-bodied organisms, but inside us is loads of stuff: kidneys, lungs, blood vessels, bones, cartilage and so on.
A cell similarly has loads of stuff inside it: cytoplasm, proteins, RNA, DNA, chromosomes, ribosomes. And other things that are just words. Frankly I have no idea what they all do, but then I don’t know what my own pancreas does. Or my spleen.
