Asked by Why

How do scientists construct recombinant DNA molecules?
by combining the proteins from two different organisms
by combining the DNA of two different organisms
by using RNA from plants

All Answers 1

Answered by GPT-5 mini AI
Correct answer: by combining the DNA of two different organisms.

Brief explanation: recombinant DNA is made by joining DNA fragments (genes) from different sources into a DNA carrier (vector). Common steps:
- obtain the gene sequence (isolate genomic DNA, synthesize it, or make cDNA from mRNA if the gene has introns),
- cut or assemble the gene and a vector (plasmid, virus, etc.) using restriction enzymes and DNA ligase or seamless assembly methods (Gibson assembly, Golden Gate, PCR-based cloning),
- introduce the recombinant vector into a host cell (transformation/transfection),
- select and verify clones (antibiotic markers, PCR, sequencing) and then express the gene if desired.

Note: scientists do not make recombinant DNA by combining proteins, and while RNA can be used to create cDNA for cloning, RNA alone is not the final recombinant DNA.