B. Anions have more electrons than protons, giving them a negative charge.
D. Cations have more protons than electrons, giving them a positive charge.
Explanation - Ions are the result of atoms or molecules that lose or gain electrons. If an atom or a molecule is positively charged then it is called as cation and if it has negative charge then it is called as anion.
Cations have positive charge because the atom has lost its electron while anions have negative charge because the atom has gained the electron. The number of protons is more than the electron in cations and less in anions.
For obtaining an adequate amount of DNA samples for DNA fingerprinting, polymerase chain reaction (PCR) can be used.
Polymerase chain reaction (PCR) is a technique that is used to amplify the DNA sample. The steps included in PCR are:-
1. Denaturation of the double-stranded DNA (at around 95°C)
2. Annealing of the primers to each of the single-stranded DNA templates ( at around 65°C)
3. Extension or elongation of the primers by considering every single-stranded DNA as a template. This elongation is carried out by <em>Taq </em>polymerase (at around 72°C).
With each cycle of PCR, the DNA sample is increased by 2ⁿ. Here, 'n' represents the number of PCR cycles.
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Learn more about polymerase chain reaction here: -
brainly.com/question/11442887
Answer:
a1* buffer
Explanation:
To buffer means “to cushion or protect.” Buffers are weak acids or bases that react with stronger acids and bases to prevent sudden changes in pH in the fluids of living organisms.
So, the correct answer is buffer! Hope this helps :)