So I’ve got a few, step by step questions about this process of protein synthesis:
1. What sort of signal “prompts” the process of protein synthesis for a certain protein—say a cell needs some Protein X made, how does it “tell” the related parts to start the process of producing that protein?
2. What part of the cell is responsible for figuring out where, in all of the genes around it, to go in order to start the process of making a specific requested protein (Protein X, in this case)?
3. How does this part “know” which sequences correlate to which proteins are requested, and therefore “know” where to target in order to start the protein’s creation? For example is it able to “read” and decode gene sequences by itself (I want to say “mentally” even though that word wouldn’t really apply here, but basically “reading” DNA without having to do it as part of a translation process) until it finds a sequence that translates to the proper code for a protein? Or is it fully just pre-programmed targeting—and if that’s the case how does *that* work then?
In: 27
So, the problem here is you’re thinking these things are “decided” when, really, it’s always happening and when things are “needed” they’re used and when they’re not they’re recycled.
It’s all just a question if electrochemical gradients and different concentrations of molecules.
For example, let’s say I have a system for sorting different size balls into hoppers where I take a slanted surface and punch holes in it of different sizes. Up near the top are 1″ holes, in the middle are 3″ holes, and near the bottom are 6″ holes. I then pour a continuous stream of mixed balls of those sizes down the ramp. The 1″ balls fall in first, then the 3″ balls, then the 6″ balls.
Eventually, the hoppers fill up to the point they’re clogging the holes and then no more balls fall so all the balls just keep running to the bottom of the ramp where they’re caught and recycled.
So then someone empties the 1″ hopper and the 1″ balls can start to fall again.
Physiological processes work in much the same way. Cells are just a bunch of assembly lines that interact with each other to create complex systems. One system might make the 1″ balls, another the 3″, etc. Then another system moves the bin from one to the next to collect them all. Then another system pours them down the ramp, and another system detects when the hoppers are full and moves them to pass on to another system that uses that size ball.
Those systems just work at the same thing all the time and if the system is super saturated there might be a system in place to trigger production to slow or stop. If it’s under saturated to speed up. If it’s chronically undersaturated it might trigger a system to build more of the systems that produce the balls. That can cause problems if levels later return to normal but you have developed these systems to overproduce things and it might take too long for them to be reversed and you could die before that’s possible unless you get more of what was needed and slowly taper off. That’s why quitting some drugs cold turkey can be dangerous, for example.
Sorry I didn’t answer your points one by one but it wouldn’t let me copy the text on my phone and I didn’t want to figure out a way to flip back and forth, so I thought it better to just address the underlying misconception/lack of information that was at the root of these questions.
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