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Biological Miracle – Wood Frog

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Re: Biological Miracle – Wood Frog

#111

Post by ImHereToVote »

w10-1 wrote: post #95

For those thinking freezing could be an option... there's a fair bit more than just avoiding ice crystals. Medical hypothermia in humans (which is just a few degrees colder) is bounded not really by not by time-cold but by restoring normal temperature too quickly. It turns out mitochondria generate a lot of free oxygen radicals when going hypoxic, and restoring oxygen quickly does the chemical damage that actually ca…

Couldn't you inject liposomal ATP into the bloodstream before the cooling process? Then mitochondria could simply be turned off. (I don't mean simple when I use the word simply)

Re: Biological Miracle – Wood Frog

#112

Post by ImHereToVote »

8n4vidtmkvmk wrote: post #86
mathh wrote: post #44

Could such a mechanism be used for interstellar travel ?

No. Article says they have 1000x sugar in their blood. When we get to 10x we tend to die.

We could replace some of the Glucose with Xylitol. Xylitol is another sugar that protects the body from Advanced Glycation End Products. AGEs are what makes glucose so dangerous.

https://www.healthline.com/nutrition/advanced-glycation-end-...

Re: Biological Miracle – Wood Frog

#113

Post by yyyfb »

card_zero wrote: post #43
pcthrowaway wrote: post #42

Now I'm wondering all kinds of things about their brain. Are they capable of forming memories, and would they retain those memories after a freeze/thaw cycle? Effectively they're dead when they freeze. I'm assuming there's no brain activity.. Which means when they thaw they're being restored to life. I wonder if any other animals experience this

Reading about them, it seems they migrate in winter (like half a mile uphill), but the adults always return to the same breeding pond in spring, so that information is stored somewhere.

Couldn't it just be algorithmic? Go uphill in the summer, then downhill until you hit water, you'll probably end in the same pond?

Re: Biological Miracle – Wood Frog

#114

Post by dangsux »

lukan wrote: post #99
durkie wrote: post #62

A great book about how animals survive super cold winters is "Winter World" by Bernd Heinrich. Bernd is a super fascinating biologist who really dives deep in to things. At one point in the book I think he was talking about chipmunks surviving winter, and it goes really fun on the first principles. Something like: "chipmunks have a surface area of X m^2, and need to maintain an internal temperature of Y˚C. If the out…

"Well I found a dead one and shoved pine nuts in to its mouth until I couldn't fit anymore, and managed to get 17 in there." That part is .. weird. What is the point except morbid humor? Chipmunks have a food storage, so they don't store nuts in their mouth. They wake up, go to the food storage and eat and go back to sleep. They don't go outside to collect more nuts in -40°C. Maybe that was the point of that calculat…

[dead]

Re: Biological Miracle – Wood Frog

#115

Post by ComputerGuru »

muzani wrote: post #74
pkoird wrote: post #7

Curious to how long the frozen structure can "survive". I wonder if it's a good idea to freeze one such frog and thaw it centuries later (an amphibian time-traveler!)

It's a bit of a fantasy that we might find a perfectly well preserved dinosaur in a glacier somewhere.

Forget the dinosaurs, we can't even preserve the glaciers themselves these days!

Re: Biological Miracle – Wood Frog

#117

Post by oharapj »

8n4vidtmkvmk wrote: post #83
nine_k wrote: post #73

Earlier quoted context omitted.

It doesn't, even in humans. There is an independent circuit of special muscle cells right on it that keeps it beating. So starting and stopping the heart in a controlled manner is pretty interesting, because it has to be well-timed, and there are few obvious and reliable inputs to control it, especially when thawing.

Why doesn't my heart keep beating if my brain dies then? Or would it?

Probably because the brain controls breathing and so the oxygen runs out quickly

Re: Biological Miracle – Wood Frog

#118

Post by wkjagt »

> No heartbeat. No breathing. For the entire winter, the wood frog is like a lump of hard, frigid, icy stone carved in the shape of a frog. But it’s alive, in a state of suspended animation.

I find it hard to grasp what is still alive about the frog. I mean, it's not dead so there must be something happening inside the frozen frog? How does it compare to a dead (and frozen) wood frog?

Re: Biological Miracle – Wood Frog

#119

Post by Qem »

crazygringo wrote: post #37
olejorgenb wrote: post #14

Earlier quoted context omitted.

- Artificial experiment [1]: no longer than 3 months (but see disclaimer) - New study [2]: 7 months (with 100% survival rate) So further study seems to be needed. [1] https://journals.biologists.com/jeb/article/216/18/3461/1160... [2] https://journals.biologists.com/jeb/article/217/12/2193/1211...

If kept in pristine conditions (perfectly sealed to prevent evaporation leading to dehydration, deep freeze), is there a particular chemical needed for life that we might expect to break down first? Since chemical reactions happen in the freezer just slower...

> Since chemical reactions happen in the freezer just slower.

Can't the gross just be kept at artificially lie temperatures to lengthen the stasis time? Say, -100C or even lower?

Re: Biological Miracle – Wood Frog

#120

Post by jounker »

lukan wrote: post #99
durkie wrote: post #62

A great book about how animals survive super cold winters is "Winter World" by Bernd Heinrich. Bernd is a super fascinating biologist who really dives deep in to things. At one point in the book I think he was talking about chipmunks surviving winter, and it goes really fun on the first principles. Something like: "chipmunks have a surface area of X m^2, and need to maintain an internal temperature of Y˚C. If the out…

"Well I found a dead one and shoved pine nuts in to its mouth until I couldn't fit anymore, and managed to get 17 in there." That part is .. weird. What is the point except morbid humor? Chipmunks have a food storage, so they don't store nuts in their mouth. They wake up, go to the food storage and eat and go back to sleep. They don't go outside to collect more nuts in -40°C. Maybe that was the point of that calculat…

The number of seeds that fit into a cheek pouch determines calories transferred per trip to storage.

Knowing this number will be critical for any modelling of chipmunk energetics.

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