What would happen when one grows a recombinant bacterium in the bioreactor but forget to add antibiotic to the medium in which the recombinant is growing?

Explanation

### Step-by-Step Solution:

1. **Understanding the Role of Antibiotics**: In recombinant DNA technology, antibiotics are often used in the growth medium to select for bacteria that have taken up a plasmid containing an antibiotic resistance gene. This ensures that only those bacteria that have successfully incorporated the plasmid can survive and grow.

2. **Absence of Antibiotic**: If a recombinant bacterium is grown in a bioreactor without the addition of antibiotics, there is no selective pressure on the bacteria. This means that there is no mechanism to ensure that only those bacteria containing the plasmid will survive.

3. **Effect on Plasmid Retention**: In the absence of antibiotic pressure, the recombinant bacteria may start to lose the plasmid. The plasmid, which carries the gene of interest, is a metabolic burden to the bacterial cells. Without the need to survive against antibiotic pressure, the bacteria may shed the plasmid to conserve energy and resources.

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