Predict which of the following DNA oligonucleotide probes would have the highest melting temperature (Tm) when hybridizing to the target sequence 5'-GTGCCTGAATGCAATGTCA-3'
a. 3'-CACGGA-5'
b. 3'-CATGGA-5'
c. 3'-TTACAG-5'
d. 3'-TTACTG-5'
A
DNA with more cytosine and guanine molecules require more heat [energy] to break the three hydrogen bonds formed between these two bases, in contrast to adenine- and thymidine-base pairing, which has only two hydrogen bonds. In addition, single nucleotide mismatches that re-duce the complementarity of the hybridization (i.e. no hydrogen bonds formed between noncom-plementary bases) will lower the melting temperature.
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When tropical forests are cut for agriculture, they often do not produce highly productive crop growth
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The movement of water through a plant is
driven by
a. the drying power of the air. b. osmosis. c. active pumping using ATP. d. root pressure. e. a combination of more than one of these
A digestive tract is complete if it
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