3 ms·
Not all are? Largest eukaryote: https://en.wikipedia.org/wiki/Valonia_ventricosa https://en.wikipedia.org/wiki/Valonia_ventricosa largest prokaryote: https:
by chasil 4mo ago
Not all are?
Largest eukaryote:
https://en.wikipedia.org/wiki/Valonia_ventricosa https://en.wikipedia.org/wiki/Valonia_ventricosa
largest prokaryote:
https://en.wikipedia.org/wiki/Thiomargarita_namibiensis https://en.wikipedia.org/wiki/Thiomargarita_namibiensis
- DaveSchmindel 4mo ago> 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 does so by breaking the surface area-to-volume rule, filling between 65–80 percent of its internal volume with an empty vacuole. In other words, it pushes most of its molecules to the cell periphery, thus shortening diffusion distances. There is also a captioned image of bubble algae in the post.
- cwmoore 4mo agoInteresting topology. How empty is the vacuole?
- trumpdong 4mo agoempty in terms of normal cell components, apparently it stores relatively huge amounts of nitrates that are a necessary energy source for it
- magicalhippo 4mo agoRather large gas tank: Collected and stored sediment samples were found to have surviving T. namibiensis cells after over two years. The cells had no access to any added sulfide or nitrate during this time. In the surviving cells, there was a notable size decrease. To survive without growing the cells depended on the nutrient stores of the central vacuoles.
- trumpdong 4mo agoIndeed. It says they rely on two different substances which normally don't mix (nitrates and sulfites), presumably because if they were both present at the same time they'd react with each other directly without the bacterium extracting any energy from that. So they live in places that sometimes have one and sometimes the other, and have to store one of them until the other comes along, which can be years. Or that's how I read it.
- vasco 4mo ago> This is in line with biology’s only rule: namely, there are exceptions to every rule! Nice paradox
- embedding-shape 4mo agoThose still seem kind of small? Why not the size of an mature olive tree for example? I'm guessing the article may answer this, haven't gotten that far yet.
- malfist 4mo agoWhen they invade your saltwater aquarium, you won't think they're small. They can get up just slightly larger than a marble
- MagicMoonlight 4mo ago[dead]
- ssivark 4mo agoIsn't the ovum supposed to be a single cell? Eggs of various species can be substantially larger than this.
- lmm 4mo agoYes. I remember reading that Ostrich eggs are the largest single cells (in terms of mass/volume; Blue Whale nerve cells are longer).
- deleted 4mo ago[deleted]
- mr_toad 4mo agohttps://en.wikipedia.org/wiki/Xenophyophorea https://en.wikipedia.org/wiki/Xenophyophorea
- OrderlyTiamat 4mo agorelatedly, foraminifera are single cellular organisms that can grow up to 20 cm! https://en.wikipedia.org/wiki/Xenophyophorea https://en.wikipedia.org/wiki/Xenophyophorea
- AgentMasterRace 4mo agoExactly
- acheron 4mo agoThere’s also the one that almost ate the Enterprise. https://en.wikipedia.org/wiki/The_Immunity_Syndrome_(Star_Trek:_The_Original_Series) https://en.wikipedia.org/wiki/The_Immunity_Syndrome_(Star_Tr...
- teravor 4mo ago> The entire cell contains several cytoplasmic domains, with each domain having a nucleus and a few chloroplasts. it reinvented being multi-cellular
- api 4mo agoIt uses container based virtualization under a single host kernel instead of VM based virtualization.
- shevy-java 4mo agoAgreed. Humans draw rather arbitrary distinctions. It was quite funny in regards to viruses, aka parasite. Mimivirus are still a parasite, of course, but they even encode genes for metabolic pathways and are larger than some bacteria. See: "The Mimivirus is a giant virus that infects amoebae and was long considered to be a bacterium due to its size." https://pmc.ncbi.nlm.nih.gov/articles/PMC9133948/ https://pmc.ncbi.nlm.nih.gov/articles/PMC9133948/ Although for me, I always used the definitions through the genetic information available (genome). So as long as a virus still is a parasite, I'd hold up that definition. It will be interesting when viruses are found that are even closer to a cell, e. g. some life cycle where they could switch between parasitism and stand-alone metabolism (or some hybrid in between; I mean if they can encode whole metabolic pathways, at the least some or some parts of it, the threshold here should not be impossible to overcome, and then the whole definition of a virus also has to be adapted since it would no longer make sense).
- chasil 4mo agoPerhaps what you are seeking "retrotransposons," an endogenous retrovirus. https://en.wikipedia.org/wiki/Retrotransposon#Endogenous_retrovirus https://en.wikipedia.org/wiki/Retrotransposon#Endogenous_ret...
- deleted 4mo ago[deleted]
- reubenswartz 4mo agoThese both feature large central vacuoles, lending support the thesis of the article that the cubic growth in volume outstrips the quadratic increase in surface area for transferring nutrients and waste across the cell membrane.
- shevy-java 4mo ago> largest prokaryote: Actually the wikipedia article states: "It is the second largest bacterium ever discovered" > The largest T. magnifica cell Volland found was 2 centimeters tall https://www.science.org/content/article/largest-bacterium-ever-discovered-has-unexpectedly-complex-cells https://www.science.org/content/article/largest-bacterium-ev... Granted, they are grouped both in Thiomargarita. 2cm is pretty gigantic. What I always found more interesting was that they don't merely have just one genome.