What is relationship between restriction sites and a restriction map

A restriction map is a map of known restriction sites within a sequence of DNA. Restriction mapping requires the use of restriction enzymes. In molecular biology, restriction maps are used as a reference to engineer plasmids or other relatively short pieces of DNA, and sometimes for longer genomic DNA.

lysosome is this part of the cell is surrounded by a very thick outer membrane to protect the rest of the cell from its strong enzymes.

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