fly cryogenesis experiment.

[cameron marical]

hey. so many organisms have an adaptation where they supply extra glucose to their blood and the water in their cells seep into vacuoles in the cells and out of the cells to stop any damage from the crystalization of the water due to freezing from happening.{please correct me if im wrong} its called cryogenisis. im sure you guys already know this but i thought itd be a good starter to this post.

 

i know that wood frogs just turn into blocks over the winter and then later thaw out with the oncoming of spring. and many other insects and eggs like mantis eggs and some fruit flys.

 

im using fruit flys for this one.

 

i will to have 4 sets of subjects and 1 control.i will feed all equaly for 2 days before my testing begins. milk,sugar, water, and of course, fruit.

 

subject1: i will leave out as a control, and feed it a normal healthy fly diet.

 

subject2: i will {after the 2 days period where i will all feed equally and try and equal them all out} put in the freezer for 1 day.

 

subject3: i will put in the freezer for 1 week.

 

subject4: i will put in the freezer for 30 days.

 

the purpose of this experiment is to see how long a fruitfly can live in cryogenesis. also, to see how long {if they can live for extended time periods being frozen} the lifespan of the fruit fly extends if it is frozen for an extended amount of time.

 

my hypothesis: i think that the control will die faster than the subjects undergoing cryogenesis due to less body motility and usage. i belive that the flys will live in cryogenis state for at least 1 day. subject4 i am unsure about, but am hoping they will live through 30 days of cryogenesis.

 

this experiment is out of curiosity alone. i will get the fruit flys from leaving some fruit to rot in a container where fruit flys can only get in and not out. then i will wait until a nice new fresh batch of maggots pops up and will seperate them into the 5 sets mentioned and feed equally until cryogenesis is induced.

 

is this experiment flawed? interesting?

 

thank you.

[iNow]

Two quick thoughts after a quick read of your post.

 

1- You probably want multiple flies in each group. Subject (maybe 10 or 20 of) them to each condition, and average the response. Single/individual flies may have differences you were not expecting that could skew you results (basically, you may measure a difference, but it could have nothing to do with your experimental conditions... it could relate to a difference in that one fly you used... by using multiples, you can average the effect and trust the result to be more related to your experimental condition).

 

2- Placing something in your home freezer may have the same effect on all groups, and is NOT cryogenics. What happens in the freezer is that stuff freezes too slowly, so ice crystals form. The slower it freezes, the larger the crystals that form, and the more tearing and shearing of cells occur. Basically, the ice crystals act like little knives and daggers ripping the cells apart slowly... shredding them as they grow. I would think that every fly you place in the freezer would be damaged in the same way... they all have their cells shredded during the first few hours... and this damage would prevent any meaningful differences from being noticed regardless of how long you ultimately leave them in there. I think that you'd want to try using something more standard to achieve the freezing. I think cryogenics might use liquid nitrogen, but you should look into that since I'm not sure. I just don't think a standard kitchen freezer is going to get cold enough, nor cold enough quickly enough, to achieve what you want.

 

 

Interesting ideas, though. Even with my concerns above you'll still learn something no matter how you perform the experiment. Good luck with it all.

[cameron marical]

ya i planned to have like 3-5 of them per set. but it all depends on how many maggots i can find in one litter.

 

i didnt think about temperatuer differences from the freezer and the outside of winter. your may be right.i might just crank up my freezer and hope for the best. my brother put a fly in the freezer, and once it came out it appeared to be dead for about a minute then it took of, so im hoping it will work.

 

i think that maybe the bugs need to have the time of a slow freezing process for getting the water from the cells just enough outside of the protoplasm so that the crystals cant form close enough to damage the cells or anything else thats needed, and im curios to see if liquid nitrogen will give the cells enough time to do that. i might be wrong though. i think ill try it with both. have 8 sets if subjects{4 flys per subject} and 1 control. 4 subjects in the freezer, 4 in the liquid nitrogen, and then have them for different amounts of days {mentioned in first post}.

 

thanks for the idea.

Edited April 26, 2009 by cameron marical

[sobe]

what about flys without food? the food could expand wile freezing and burst the stomach. also, i think putting them in the freezer might freeze them too slowly, and so i suggest putting im the fridge first. the slower they freeze the smaller ice crystals will be.

[iNow]

what about flys without food? the food could expand wile freezing and burst the stomach.

Items contract when they freeze, not expand. Water is a notable exception. Food, however, would shrink during freezing.

 

 

also, i think putting them in the freezer might freeze them too slowly, and so i suggest putting im the fridge first. the slower they freeze the smaller ice crystals will be.

You've got this backwards. The slower they freeze, the LARGER the ice crystals. The faster they freeze, the smaller the crystals.

 

See my thread about homemade ice cream for more about exactly that.

[sobe]

yes, but the food has some water in it, and water is one of the things he'll be feeding them, so could this affect it?

 

 

 

and that could be right, but i believ i saw that your suposed to place meats in a refridurator before freezing, because the ice crystals are smaller and puncture the cells...of corse i could be wrong and ill go check myself now to make sure

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ok as for the freezing thing, you were right, i was foolish to argue against you

 

 

hear is a guide i found to prove your point lol http://everything2.com/title/Freezing%2520biological%2520samples

[iNow]

also, i think putting them in the freezer might freeze them too slowly, and so i suggest putting im the fridge first.

I just wanted to let you know that you were correct about this point. Putting it in the refrigerator first will lead to smaller ice crystals. The reason for this is that it will be closer to its freezing point after having it in the fridge. This means that when you put it in the freezer after cooling it in the fridge it will freeze more quickly (since it was cooler when you started) and the crystals will hence be smaller. Quicker freeze = smaller crystals, and your suggestion about the fridge will help it to freeze more quickly.

[hermanntrude]

very interesting experiment idea. Let us know how it goes. Be sure to measure all temperatures and use the biggest groups of flies as you can. More data are better. 20 would be a minimum group size. If you say you already saw a fly survive a dump straight into the freezer, try it directly... no point complicating the experiment with an extra step.

 

I wonder if feeding them extra glucose would help with the process?

[sobe]

I just wanted to let you know that you were correct about this point. Putting it in the refrigerator first will lead to smaller ice crystals. The reason for this is that it will be closer to its freezing point after having it in the fridge. This means that when you put it in the freezer after cooling it in the fridge it will freeze more quickly (since it was cooler when you started) and the crystals will hence be smaller. Quicker freeze = smaller crystals, and your suggestion about the fridge will help it to freeze more quickly.

 

 

 

ok, the artical i posted confused me a bit but i thought it proved your point, but any ways thanx i thought of it from an old episode of good eats the cooking show, talked about keeping frozen meats better preserved and such.

[iNow]

Well, we're both correct in a sense. You were right that cooling something first in the fridge will minimize ice crystal formation when it's placed in the freezer.

 

I said that the faster something cools (and freezes), the smaller the ice crystals which form (they don't have as long to grow).

 

Both of these points are accurate, and the compliment one another rather well. Enjoy.

[sobe]

If you say you already saw a fly survive a dump straight into the freezer, try it directly... no point complicating the experiment with an extra step.

 

 

i disagree, its a small step that i can only see it helping the experiement, directly freezing them, they might survive, but probly with some tissue damage, and therefore not as healthy. you want to do it asbest as you can, dont be lazy, it might even increase the survival rate.

 

 

infact, maby double the batches and make one half of the flys direct freezed, and the other half slow frozen. and maby slow and fast thawing?

[cameron marical]

i disagree, its a small step that i can only see it helping the experiement, directly freezing them, they might survive, but probly with some tissue damage, and therefore not as healthy. you want to do it asbest as you can, dont be lazy, it might even increase the survival rate.

 

im not sure if flys can withstand cold temperatures just below freezing though.i might be wrong, this is just a speculation.

 

 

infact, maby double the batches and make one half of the flys direct freezed, and the other half slow frozen. and maby slow and fast thawing?

 

though my amount flys have increased by 3x since the beginning if i do this, i think i will. do you guys think that this{pre-freezing in the freezer first} should be applied to the frozen nitrogen set too? im thinking that it will be of no use of if anything be negative for the flys because of small ice crystals bulding up from the slow fridge freezing versus the instant freezing of the liquid nitrogen.

 

how long do you guys think i should keep them in the fridge before freezing?

 

im curios how i should go about submerging the flys in the liquid nitrogen itself...should i submerge them all at once inside of a container with holes? will they freeze together and cause trouble?

or do them one at a time...any suggestions?

 

I wonder if feeding them extra glucose would help with the process?

 

good thought. maybe ill split half of all the flys im testing on and half the containers theyll be in and have the extra glucose fed ones on one side and the normal diet ones on the other.

Edited April 28, 2009 by cameron marical