Insulin is a protein hormone produced by the pancreas in humans that regulates the metabolism of food. In 1978, scientists successfully spliced the human gene for insulin into the bacterium E. coli. This enabled insulin to be produced by the bacteria. This insulin could then be extracted and used as a medication to treat people with diabetes. Since then, the gene for insulin has also been spliced into yeast cells and plant cells for the same purpose.
Which explains why different species are able to produce insulin?
A.
All species contain DNA, which naturally rearranges itself into any gene.
B.
The gene for insulin originated in bacteria and was passed on to other species over time.
C.
Insulin is a protein that all species produce in order to regulate metabolism.
D.
All living organisms have genes that are made up of the same components.