GENETICS AND EVOLUTION
MOLECULAR BASIS OF INHERITANCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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right-or-left-handed double helix and antiparallel strands
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right-handed double helix and antiparallel strands
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right-handed single helix
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right-handed single helix and parallel strands
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Detailed explanation-1: -Watson and Crick’s model of DNA. The structure of DNA, as represented in Watson and Crick’s model, is a double-stranded, antiparallel, right-handed helix.
Detailed explanation-2: -The strands of a DNA double helix are said to be “antiparallel” because the have the same chemical structure, but are opposite in direction.
Detailed explanation-3: -The right-handed helix conformation called B-DNA is the dominant form in vivo. The diameter of the helix is 20 Å and one turn consists of 10 bp. A-DNA also displays a right-handed helix conformation and its diameter is 23 Å: one turn contains 11 bp. The left-handed helix conformation of DNA is known as Z-DNA.
Detailed explanation-4: -1: Antiparallel Strands: In a double stranded DNA molecule, the two strands run antiparallel to one another so one is upside down compared to the other. The phosphate backbone is located on the outside, and the bases are in the middle.
Detailed explanation-5: -The double helix is a description of the molecular shape of a double-stranded DNA molecule. In 1953, Francis Crick and James Watson first described the molecular structure of DNA, which they called a “double helix, ” in the journal Nature.