December 20, 2010

Torah Kachur

Winter.  The penultimate season where Canadians, Russians and Scandanavians get our grit, determination and dark Russian novels.  Our toughness for withstanding cold is nothing compared to the common wood frog (Rana sylvatica).  These frogs freeze completely solid for our epic season and then comes back to life when summer (finally) arrives. 


A cute version:




The human body can show freezing, or frostbite in 5 minutes in temperatures of -50ºCelcius (or -55 Fahrenheit) which includes the enigmatic wind chill factor.  For those of you in warmer climes, us Canucks get bragging rights, -50 is a yearly occurence up here in the Great White North.  Frostbite is caused by tissue death because of the sharp ice crystals that form when water freezes.  The ice crystals, to a cell, are daggers that pierce the membrane, rupture cell integrity and basically screw up the cell so that it dies.  The other major problem of freezing is that the available water for survival is now trapped as ice causing dehydration of the tissue. 


The wee little froggy has found ways around both of these problems - first the frog (we'll call him Hoppy) secretes urea into the tissue...that's pee.  Yup, the frog pees into his own body; the urea is a cryoprotectant so that when ice crystals form, they don't penetrate the entire body.  Then, Hoppy pumps his cells full of sugar to up to 100 times the normal amount so that the sugar doesn't allow the inner parts of the cell to freeze.


Finally, Hoppy and his fellow brethren actually initiate ice crystal formation in their blood just at freezing so that the whole process is drawn out into an agonizingly long period.  Imagine trying to freeze to 'death' slower.  But this slow freezing gives the body and metabolism time to adjust to the new phase.   And finally - blood full of pee, cells full of sugar and icicles primed to form - we get a Frog-cicle.

And now the not-so-attractive frozen version:






I think I'll stick to long underwear and central heating.


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