In order to insert a human gene into a bacterial plasmid, first a _____ enzyme is used to cut up the DNA and form 'sticky' ends on the gene and the plasmid. Then, the enzyme DNA______ is used to seal the human gene into the plasmid. They can now be allowed to reproduce, cloning the DNA, or the bacteria can be caused to _______ the human gene, producing pure human protein.

Explanation

To insert a human gene into a bacterial plasmid, follow these steps:

1. **Use a Restriction Enzyme**: The first step is to use a restriction enzyme to cut the DNA at specific locations. This enzyme creates 'sticky' ends on both the human gene and the plasmid. These sticky ends are important because they allow the DNA fragments to bind together easily.

2. **Seal with DNA Ligase**: After the human gene has been inserted into the plasmid, the next step is to seal the DNA. This is done using the enzyme DNA ligase, which joins the sugar-phosphate backbone of the DNA strands, effectively sealing the human gene into the plasmid.

3. **Reproduce or Express the Gene**: Once the plasmid contains the human gene, it can be introduced into a bacterial host. The bacteria can then be allowed to reproduce, which will clone the plasmid and the inserted human gene. Alternatively, the bacteria can be induced to express the human gene, leading to the production of pure human protein.

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