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Comment by johndoe42377 | Hacker News Reader

Please show any timing at cellular level. Thank you.

I'm not often this blunt, but you have no idea what you're talking about here. There are explicit clocking systems both within and across cells and they are very important for regulating many biological processes. Please read this article about how they literally use an analog clock synchronization algorithm (something that has been discussed in the literature for computers, too!) to make sure their internal clocks roughly match the macroscopic clock:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6585513/

This is a conceptual mess.

Synchronization does not imply time. It implies synchrony, which is a mechanical notion. Electric signals are used everywhere in life for that purpose.

What they called clocks are not clocks. No more than a frequency generator is a clock.

To an electronic engineer a frequency generator in fact is a clock.

A frequency generator is the essence of a clock. Why do you think we talk about clock speed in computer science? I'm honestly not sure what other definition you would even use in this context. And certainly, given that these "frequency generators" synchronize, divide time into repeating windows of roughly the same length, and are used to schedule and regulate biological processes, it is a bit bizarre for you to say that they somehow have nothing to do with timing.

What are you on dude? In what universe does synchronization not involve time? Synchronization is defined as "Occur at the same time or rate".

Even if you're so pedantic that you're going to say something like "it could mean rate and not time". Rate also means "the number occurrences in a specific time interval". So how exactly are you contorting your logic to come to this conclusion?

Not saying I agree with GP but there are 2 distinct notions of time. One is related to durations, and the other is absolute time (aka wall time). Clocks measure wall time, not durations. Cellular processes probably don’t care about wall time.

Wall clock time is pretty much only measured in practice as some offset relative to some repeating process, though (e.g. hours since start of day). Cells certainly have processes that repeat on a daily basis, at different offsets from the beginning of the day; they may not actually be measured by counting ticks (the jury's still out on exactly how they do it, I think?), but the effect is similar.

If things happened out of order, the cell wouldn't work at all. There are a lot of different signal pathways that ensure timing is correct. You can take a look at even the most basic functionalities like DNA replication, or energy exchange. And the cell is not timed only in regards to itself, but based on the system it lives in, too - and that system is timed too, repeat x1000000.

Humans (and other living beings) can work with such low amount of waste heat and intake energy only thanks to atomically precise clocking.

Perhaps the above commenter is talking about the perceived scale or speed of time? Order of events certainly seems to matter.

At the same time, order of events is also a certain way of modelling something. There may be alternative models which can be meaningful without the order of time. But most (probably all) models are designed with the way we perceive time in mind.

DNA replication is a structural pattern matching and has nothing to do with time.

Moreover, it is so stable exactly because it has neither the notion of time nor counting.

Maybe watch a video about the process on Youtube? What you're saying is correct in a very abstract sense, but does not really convey what is actually happening inside the cell. Timing is extremely important because if the proteins worked out of order (which is often different based on signals), wrong DNA would come out. Also, other systems inside and outside the cell have influence on the replication (you don't always replicate the whole DNA, sometimes it's necessary to not finish the whole process and do something else as the last step, etc). And replication is not stable at all, btw, but there is very good error handling. And don't get me started on DNA activation.

Cells literally have a clock pathway.

> Maybe watch a video about the process on Youtube?

Any recommendations?

I like this one: https://youtu.be/7Hk9jct2ozY

This one is about 'garbage collection' of cells: https://youtu.be/DR80Huxp4y8

That’s awesome. I learned more about DNA in 5 mins than all my biology classes.

One more time. DNA replication relies only on particular structures and enzimes to transform these. There is no notion of time whatsoever. Only availability of structural elements, and concentration. Everything is decoupled and feedback loops based.

And sequences of actions are maintained by pipelining of physical molecular structures - each enzime recognizes it's own unique patterns. That is it.

In old times this was called principle-guided science.

Understanding of principles spares one from knowing all the details.

The problem here is that what everyone recognizes as clocks, you don't. The scientific consensus is elsewhere though. There is no reason to call a clocking pathway anything else if its purpose is to determine after how much time should something happen.

https://www.quantamagazine.org/how-the-bodys-trillions-of-cl...

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