The desert is hot and dry, while the tundra is cold and frozen. In a desert climate, anatomical structures and behaviors that protect an organism from heat are useful adaptations. Most organisms have adaptations that help them conserve water, because water can be scarce in desert climates. For example, many organisms in the desert are nocturnal, which means they’re most active at night when temperatures are cooler.
That scrape on our knee will never heal and the blood loss due to bleeding will never be replaced. This is because RNA is inside of cells and without the ability to create new RNA you cannot replace missing cells. So the scrape will never heal if your cells cannot create new RNA.
