Step-by-step explanation:
A gene from one organism can be expressed in another, because the size and structure of all genes is exactly the same (of course, the code is different). Scientists insert a gene from organism “A” into the gene of organism “B”. They do this by first cutting the gene of organism “B”, and inserting gene “A”. Then, (this wasn’t in the lesson. I’m just guessing) certain proteins inorganism “B”, which are responsible for gene repair, connect gene “A” to genes “B” properly. When it is time for transcription to take place, the enzyme/proteins read the new DNA also, including it in the RNA sequence