BIOLOGY
NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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25% A/T and 75% C/G
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50% A/T and 50% C/G
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75% A/T and 25% C/G
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100% A/T and 0% C/G
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Detailed explanation-1: -A DNA molecule consisting only of guanines and cytosines is much more stable and melts around or above 100°C depending on the concentration of NaCl.
Detailed explanation-2: -The helical structure of double-stranded DNA is destabilized by increasing temperature. Above a critical temperature (the melting temperature), the two strands in duplex DNA become fully separated.
Detailed explanation-3: -The stability of the DNA double helix depends on a fine balance of interactions including hydrogen bonds between bases, hydrogen bonds between bases and surrounding water molecules, and base-stacking interactions between adjacent bases.
Detailed explanation-4: -Because G:C pairs have an additional hydrogen bond than A:T pairs, the GC-rich genomes are expected to be thermally more stable in high-temperature environments [23].