the answer to your question is POLLUTION
Answer: Option A) nucleus
Explanation:
Prokaryotic cells lack nuclear envelope, thus the nucleus is absent in Prokaryotic cells.
On the other hand, eukaryotic cells possess membrane bound nucleus and nuclear envelope.
Thus, nucleus is the answer
The use of restriction enzymes and electrophoresis to generate a map of the DNA molecule is known as RESTRICTION MAPPING. This technique is used to map an unknown fragment of DNA.
Restriction enzymes are enzymes that cut a DNA fragment at specific nucleotides sites, thereby generally smaller fragments of DNA.
Restriction mapping is a strategy used to map unknown fragments of DNA by digesting them into smaller fragments and then identifying the specific sites of the DNA breakpoints.
Restriction mapping can then be used to create a diagram of fragments of DNA marked with specific sites where they are cut by specific restriction enzymes.
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Oxygen is an electronic which can be defined as pure substance..we breath in oxygen and breath out carbon dioxide