Why are cells small?

chasil

Not all are? Largest eukaryote: https://en.wikipedia.org/wiki/Valonia_ventricosa largest prokaryote: https://en.wikipedia.org/wiki/Thiomargarita_namibiensis

WorkerBee28474

Another answer is: They're not - at least in some plants: https://en.wikipedia.org/wiki/Valonia_ventricosa https://en.wikipedia.org/wiki/Acetabularia

socalgal2

Cells are small? compared to what? An ostrich egg is a single cell

kayo_20211030

> A simplistic answer is that evolution has made each cell the size best suited to its function. Yeah. That's probably it. Really, it probably is the right answer.

limbero

Nitpick maybe, but I don't think oocytes are the largest cells, it pretty much has to be some sort of neuron. A sensory neuron for eg. someplace in the foot will be almost as long as the person is tall, and even if the neuron is extremely thin, it's gotta beat the oocyte for volume.

gilleain

Surface area to volume ratio?

Imnimo

This reminds me also of this paper: https://www.pnas.org/doi/pdf/10.1073/pnas.1115585109 "The allocation of all metabolic resources to maintenance purposes limits the size of the smallest prokaryotes and largest unicellular eukaryotes, whereas an inability to meet the ever-increasing biosynthesis rates limits the largest prokaryotes and smallest unicellular eukaryotes. Metabolic constraints for larger eukaryotes are relieved by alternative reproductive strategies and multicellularity."

Terr_

Reminds me of: "Gravity plays a role in keeping cells small" [0] [0] https://www.princeton.edu/news/2013/10/24/gravity-plays-role...

why_at

I've recently gotten into microscopy as a hobby and comparing the relative size of microbes is really interesting. There are entire animals (tardigrades for one) which can be smaller than some single celled organisms. There are even single celled organisms which will prey upon and eat multicellular animals.

ablob

I feel like keeping the amount of molecules the same within the simulation needs to be justified. How would it look like if the average amount of molecule was the same across a um?

firefax

maybe god is small too?

BurningFrog

Cells are small compared to humans because we're made up by around 3×10¹³ cells.

nxy

Perhaps cells are small in the first place is for efficiency. It's more efficient to perform a set of tasks with trillions of these cells in unison than one big blob.

dennyabraham

Aside from the anthropocentric view that cells are relatively small because we are made of many of them, the increases in size of lifeforms past that of individual cells is a matter of exceeding thermodynamic and informational limits. I highly recommend the book _The Vital Question_ as an intro to the systemic view of this kind of biological complexification

RataNova

I like explanations like this because they make biology feel much less arbitrary

warrantisall

Cells are bad.