Question

which of the following statements is true?
a bacteria can produce human proteins.
b vector dna is replicated inside a bacterial cell.
c cloned genes are used in medicine and agriculture.
d all of these statements are true.

Explanation:

• Option a: Through recombinant DNA technology, bacteria (like E. coli) can be engineered to produce human proteins (e.g., insulin) by inserting the human gene for the protein into the bacterial genome.
• Option b: Vector DNA (e.g., plasmids) is designed to replicate inside bacterial cells. Once a vector carrying a gene of interest is introduced into a bacterium, the vector replicates along with the bacterial DNA, amplifying the cloned gene.
• Option c: Cloned genes have numerous applications. In medicine, they are used for producing therapeutic proteins (e.g., growth hormones), developing gene therapies, and creating vaccines. In agriculture, they are used to engineer crops with desirable traits like pest resistance (e.g., Bt cotton) or improved nutritional content.

Since all statements a, b, and c are true, option d is correct.

Answer:

d. All of these statements are true.