科学素养与生活应用·英语30篇（1）

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为何某些青蛙能完全冻结又在春季无损复苏

Wood frogs in Alaska and Canada survive winter by freezing up to 70% of their body water into ice.
Special glucose proteins act as natural antifreeze, protecting cells from ice-crystal damage during deep freeze.
Their hearts stop beating, and breathing halts completely while frozen beneath leaf litter or soil.
Scientists discovered that liver cells rapidly produce cryoprotectants when temperatures drop below zero degrees Celsius.
This adaptation lets frogs endure weeks below −4°C without tissue necrosis or organ failure.
When spring arrives, thawing begins from the core outward, restoring circulation within hours.
Biomedical researchers study these frogs to improve human organ preservation for transplants.
Unlike mammals, frog cells tolerate dehydration and metabolic shutdown without triggering apoptosis.
Field biologists track survival rates using radio-frequency tags implanted before hibernation.
Understanding this process helps design better cryostorage methods for vaccines and biological samples.