Aresearcher is using the puc18 vector to introduce a human gene into bacteria. he exposes bacteria to this recombinant molecule and then grows these organisms in culture. he is very surprised to find that all of the resulting bacterial colonies are blue and survive treatment with antibiotics. what can he conclude from these results?

Based on the observation that only male crickets produce a song, you hypothesize that a male's song is a form of communication to potential mates. you set up a simple experiment to test this hypothesis. in the laboratory, you place a male snowy tree cricket in enclosure a, which is adjacent to enclosureb. in enclosure b, you place other insects, one at a time, and observe their responses to the male's song. the enclosures are designed so that the two insects being tested cannot see or smell each other, but sound is transmitted from enclosure a to enclosureb.

Dna replication occurs in preparation for

The structure of a dna molecule is best described as a. one long strand of nucleic acids b. two strands of dna nucleotides joined by hydrogen bonds c. two strands of amino acids joined by hydrogen bonds d. one long strand of amino acids