3 ms·
Although there is truth in the post, this is not entirely correct. Many chemical and biological processes take place in a much slower timescale than hundreds of
by dkural 9y ago
Although there is truth in the post, this is not entirely correct. Many chemical and biological processes take place in a much slower timescale than hundreds of thousands per second, many miles per hour etc.
These processes include DNA synthesis/cell division, transcription, the transmission of electricity / ions between neurons, and many other basic processes.
Also, Many proteins don't simply float every around the cell at these massive speeds - they form stable, localized protein complexes that keep on doing what they're doing at the same location for quite a while. That's why we can image them and make real-time movies at human scales of perception (seconds, minutes etc.).
Even more so for more complex processes - this is also why cellular motion takes quite a while - go on youtube and watch dictyostelium cells move towards folic acid. It takes quite a while, many hours in fact despite the presence of a very clear folic acid gradient as the signal.
- abecedarius 9y agoAlso, speeds like "100 times per second" should be scaled down with the size scaling, if you want a feel for mechanics. Times Square is about 1km long, and a eukaryotic cell around 10 microns, so scale by 100 million. (A pretty typical protein, 5nm across, becomes 0.5 meters across in Times Square.) From this perspective even the rapid purposeful actions the article talks about go extremely slowly: 100Hz becomes a million seconds per action -- a couple weeks. The biomolecules do whip around at random very fast -- but net progress happens only after a lot of wriggling.
- 100ideas 9y ago> Also, speeds like "100 times per second" should be scaled down with the size scaling, if you want a feel for mechanics. I'm a little confused, are you saying that the real speeds and rates in the article/this thread are all too fast by a factor of 100 million, or are you saying that its useful to perform this scaling mentally when imagining these systems to get a better intuition of their mechanics...?
- abecedarius 9y agoThe latter. Maybe I should reread the post, but it invites you to visualize a cell as Times Square -- scaling the sizes -- and then the unscaled speeds give the wrong impression within that visualization. (Mechanical properties like stiffness don't vary when you scale space and time together.) Outside of it, of course the absolute speeds are what you want to know.
- 100ideas 9y agoThanks for the clarification, I see what you’re getting at.
- AstralStorm 9y agoPart of the reason why neurons, eyes, nose and inner ear use special superstructure and electrical ion interfaces. These vastly help organize and speed up chemical transport. Cytoskeleton (which is partly responsible for cellular transport) is implicated in being part of long term memory.