Suppose you check the results of your PCR reaction by running the products on a DNA agarose gel (see an explanation of DNA electrophoresis on the next page). After doing so, you discover that there are no bands present (i. e. no products were produced from PCR). How could you explain this result?

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hope i

-lavira : )

the answer is c because it is most logical.

answer: b

coz red blood cells marrow and circulates the body for 120 days.

the last one: artificial selection/genetic engineering

plant breeding is modifying the genetic composition of the plant - but this isn't cloning (which is specifically introducing a gene into a genome). but you are artificially selecting for the phenotype that you want.

the second one is literally genetic engineering - the gene would have been cloned first and then inserted or genetically engineered into the new plant cell (the cotton).