NURSING EXAM QUESTIONS
MICROBIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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one helix strand that runs from the 5’ to 3’ direction and the other strand runs from the 3’ to 5’ direction.
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each base bonding at the 1’ position of the sugar.
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an original parent DNA strand and one newly synthesized DNA strand comprising a new DNA molecule.
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a purine always bonding to a pyrimidine.
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Detailed explanation-1: -Leading and lagging strands A DNA double helix is always anti-parallel; in other words, one strand runs in the 5’ to 3’ direction, while the other runs in the 3’ to 5’ direction. This makes it necessary for the two new strands, which are also antiparallel to their templates, to be made in slightly different ways.
Detailed explanation-2: -DNA is composed of two strands of nucleotides held together by hydrogen bonding. The strands each run from 5’ to 3’ and run in antiparallel, or opposite, directions from one another.
Detailed explanation-3: -Leading and lagging strands One new strand, the leading strand, runs 5’ to 3’ towards the fork and is made continuously. The other, the lagging strand, runs 5’ to 3’ away from the fork and is made in small pieces called Okazaki fragments.
Detailed explanation-4: -Antiparallel means parallel but oppositely directed. The two DNA chains are antiparallel, i.e., they run parallel but in opposite directions. Each DNA molecule has two strands of nucleotides. Each strand has a sugar-phosphate backbone, but the orientation of the sugar molecule is opposite in the two strands.