If we inserted an anabolic Tryptophan (trp) operon with GFP for amino acid synthesis instead, what would happen if we grew the bacteria in a agar containing excess tryptophan

Since there is presence of excess tryptophan, the trp operon will be switched off, since the bacterial need not to synthesize.

Explanation:

Understand the following.

The trp operon is a group of gene that encode biosynthetic enzymes for the amino acid tryptophan.

The transcription gene in the operon is switched off when the tryptophan is in excess but is switched on by the bacterium when the tryptophan is low, so that more tryptophan can be produced.