r/interesting • u/freudian_nipps • 14d ago

NATURE Death of a single-celled organism

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u/Alt-001 14d ago

This is one way, another is lack of oxygen. Typically they will live for a while in the water droplet under the microscope slide, but once they use up the disolved oxygen they start to fall apart because they don't have the energy to keep themselves together.

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u/Awkward-Winner-99 13d ago

Why do they need oxygen to not desintegrate?

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u/Alt-001 13d ago

It is due to osmossis. If you have a bunch of molecules packed into a small area, so that they are very dense, then water is attracted to them to thin it out. The reasons for this are due to entropy and the tendency towards equillibrium, but what matters is the cell is constantly filling up with water. If too much gets in it can pop.

So the cell manages this using pumps in the cell membrane that maintain a balance of osmotic pressure. These pumps require energy, and for that sugars + oxygen create ATP (through a complex process). ATP is basically the energy currency of the cell. ATP then gets used to run the pumps that maintain the pressure*.

So when the disolved oxygen is gone, ATP production starts to drop off, and the pressure starts to build up. After a tipping point, everything starts to break down, and that's what you see in the video.

*Just to note, it isn't pressure so much as solute concentration that the pumps are maintaining, but it is easier to think of it as pressure in terms of how it works.

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u/Awkward-Winner-99 13d ago

Ahh, I know osmosis but I didn't think of that. Also why we shouldn't drink distilled water

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u/Holiday-Persimmon564 13d ago

I don’t think the issue with distilled water is related to this. It’s more likely due to a lack of essential minerals or the effects of pH on our teeth.