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[return to "Ask HN: What scientific phenomenon do you wish someone would explain better?"]
1. umvi+go[view] [source] 2020-04-26 22:20:34
>>qqqqqu+(OP)
I would like to understand how cellular biology processes actually work. Like, how do all the right modules and proteins line up in the right orientation every time? Every time I watch animations, it seems like the proteins and such just magically appear when needed and disappear when not needed [0]. Sometimes it's an ultra-complex looking protein and it just magically flys over to the DNA, attaches to the correct spot, does it's thing, detaches, and flies away. Yeah right! As if the protein is being flown by a pilot. How does it really work?

[0] https://youtu.be/5VefaI0LrgE

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2. knzhou+Yp[view] [source] 2020-04-26 22:34:00
>>umvi+go
The issue with these animations is that they're getting rid of all the thermal noise. In reality, single proteins are flying around the whole length of the cell many times a second, just from their thermal motion. And when processes like DNA transcription happen, they're not like a regular conveyor belt -- a fraction of the time the machine will even accidentally run steps in reverse! However, if any of this were shown, the animations would become impossible to understand.
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3. chango+Kt[view] [source] 2020-04-26 23:06:04
>>knzhou+Yp
just once i would like to see the realistic animation though even if it's impossible to understand
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4. satori+Cy[view] [source] 2020-04-26 23:52:30
>>chango+Kt
https://www.youtube.com/watch?time_continue=42&v=uHeTQLNFTgU

This comes close -- It shows the jittery thermal motion of this tiny machinery, instead of nice smooth glides.

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5. mnchar+LO[view] [source] 2020-04-27 02:47:14
>>satori+Cy
Oh my that facepalm dreadful. Thank you! That gives me a new high-water mark for misleading biomolecular visualization computer graphics content. Snagged a copy.

When most everything is unmoving, it's "obvious"... well no, not to students, but... there's no pretense of doing anything other than stitching together an extremely selective set of "snapshots", to tell a completely bogus narrative of smooth motion.

Here it seems something like a Maya "jiggle all the things" option has been turned on. Making it sort of kind of look like you're being shown more realistic motion. But you're so not. It's the same bogus smooth narrative, now with a bit of utterly bogus jiggle. Those kinesin legs still aren't flailing around randomly. Nor only probabilistically making forward progress. And the thing it's towing still isn't randomly exploring the entire bloody space it can reach given the tether, between each and every "step". It still looks like a donkey towing a barge, rather than frog clinging to rope holding a balloon in a hurricane.

And given that the big vacuole or whatever should be flailing at the timescale defined by the kinesin feet, consider all those many much smaller proteins scattered about, just hanging out, in place, with a tiny bit of jiggle. Wow - you can't even rationalize that as being selective in "snapshots" - those proteins should just be blurs and gone.

And that's just the bogosity of motions, there's also... Oh well.

So compared with older renders, these new jiggles made it even harder to recognize that all the motion shown is bogus. And not satisfied with the old bogus motion, we've added even more. Which I suggest is dreadful from the standpoint of creating and reinforcing widespread student misconceptions. Sigh.

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6. dnauti+C61[view] [source] 2020-04-27 06:54:20
>>mnchar+LO
you might like this render better:

https://www.youtube.com/watch?v=DR80Huxp4y8

here's the artistic director for the inner life of the cell (the worse one) going on and on about how "beautiful" the science of biology is:

https://www.ted.com/talks/david_bolinsky_visualizing_the_won...

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7. mnchar+CP1[view] [source] 2020-04-27 14:47:17
>>dnauti+C61
> artistic

Yeah. One might for example reduce reinforcement of the big-empty-cell misconception by briefly showing more realistically dense packing, eg [1], before fading out most of it to what can be easily rendered and seen. But that would be less "pretty". Prioritizing "pretty" over learning outcomes... is perhaps a suboptimal for education content.

> better

But still painful. Consider those quiet molecules in proteins, compared with surrounding motion. A metal nanoparticle might be that rigid, but not a protein.

One widespread issue with educational graphics, is mixing aspects done with great care for correctness, with aspects that are artistic license and utter bogosity. Where the student or viewer has no idea which aspects are which. "Just take away the learning objectives, and forget the rest" doesn't happen. More like "you are now unsalvageably soaked in a stew of misconceptions, toxic to transferable understanding and intuition - too bad, so sad".

So in what ways can samplings of a protein's configuration space be shown? And how can the surround and dynamics be shown, to avoid misrepresenting that sampling by implication?

It can be fun to picture what better might look like. After an expertise-and-resource intensive iterative process of "ok, what misconceptions will this cause? What can we show to inoculate against them? Repeat...". Perhaps implausibly intensive. I don't know of any group with that focus.

[1] https://www.flickr.com/photos/argonne/8592248739

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8. dnauti+lm2[view] [source] 2020-04-27 18:13:18
>>mnchar+CP1
david goodsell's pictures are fantastic. I used to work down the hall from him!
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