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Why are cells small?

burrito.bio

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Re: Why are cells small?

#31

Post by fluoridation »

kayo_20211030 wrote: post #5

> 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.

That just kicks the can forward one step. What parameters control the optimal size of a given cell?

Re: Why are cells small?

#33

Post by hatthew »

NoMoreNicksLeft wrote: post #24
hatthew wrote: post #18

Earlier quoted context omitted.

Some back of the envelope math says this is true. A conservative estimate for the size of an alpha motor neuron axon is 10μm diameter and 1m long, which already puts it over an order of magnitude larger than the 4,000,000µm³ oocyte quoted in the article.

This almost feels like cheating. Why not count hair follicles with hair attached then?

In addition to what mbauman said, hair follicles and the hair itself are not single-cell. I can't immediately find the composition and average cell size, but even a long and thick strand of hair is less than 2 orders of magnitude larger than the largest neurons. I doubt any individual hair cell is very large.

Re: Why are cells small?

#35

Post by 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.

Re: Why are cells small?

#36

Post by 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?

Re: Why are cells small?

#37

Post by cwmoore »

DaveSchmindel wrote: post #10
chasil wrote: post #2

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

> Cell sizes are not fixed, however, even within a single species. Cells often swell as they increase their production of proteins and metabolites in preparation for division. This is in line with biology’s only rule: namely, there are exceptions to every rule! > Case in point: a giant bacterium called Thiomargarita magnifica can extend about one centimeter in length, so large that it can be seen by the naked eye. It…

Interesting topology. How empty is the vacuole?

Re: Why are cells small?

#38

Post by taneq »

kayo_20211030 wrote: post #5

> 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.

Why are things the way they are? Because it works better. Simple, really. :D

Re: Why are cells small?

#39

Post by acheron »

chasil wrote: post #2

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

There’s also the one that almost ate the Enterprise. https://en.wikipedia.org/wiki/The_Immunity_Syndrome_(Star_Tr...

Re: Why are cells small?

#40

Post by CrazyStat »

limbero wrote: post #7

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.

Giraffes neurons can be up to 15 feet long. Blue whales are speculated to have neurons up to 100 feet long, though they've never been directly observed (dissected).
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