20 is the Number of Neutrons of potassium.
Answer:
Global warming may cause more icebergs to melt than are created. This would lead to higher sea levels. Sea levels may rise above land masses located at low elevations. As a result, the animals who lived in these areas may find their habitats shrinking and resources depleting, causing their population size to decrease. If there are particular species that were only able to survive in the areas now covered by water, they may very well become extinct.
Nuclear DNA is present in the nucleus of eukaryotic cells. When working with the DNA samples, the best source of nuclear DNA is hair root that anchors the whole shaft of hair. Hair root possesses cells that are called as keratinocytes.
It's the Immune system!
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