The wood frog (*Lithobates sylvaticus*) possesses an extraordinary ability to survive the freezing of its bodily fluids during northern winters. As temperatures drop below freezing, the frog initiates a complex physiological response: it ceases breathing, its heart stops beating entirely, and up to sixty percent of its body water turns to ice. Crucially, the frog prevents lethal cellular dehydration and shrinkage by flooding its internal organs with high concentrations of glucose, which acts as a natural cryoprotectant. This specialized sugar lowers the freezing point inside the cells, keeping the intracellular water from freezing even as ice forms in the surrounding extracellular spaces.
According to the passage, the wood frog prevents lethal cellular dehydration and shrinkage during freezing temperatures by doing which of the following?
- Saturating its vital organs with glucose to keep the water inside its cells liquid.Cevap
- BForcing water out of its cells into extracellular spaces to raise the glucose levels in its internal organs.
- CFreezing the water inside its cells to prevent ice from forming in the surrounding extracellular spaces.
- DCeasing its breathing and heartbeat to actively pump cryoprotectants into its extracellular water.