My Answer: <span>When only a small amount of DNA is available, such as at a crime scene.
Hope I helped! :D</span>
Cell membranes help organisms maintain homeostasis by controlling what substances may enter or leave cells
<span>An
atom with an atomic number of 12 has 12 protons. Because the mass
number is the sum of the protons and neutrons, the mass number would
need to be at least 12. I hope this helped!
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