PATHOLOGY MCQ
CELL DAMAGE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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behind the deoxyribose sugars
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between the nitrogen bases
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underneath the phosphate groups
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between the carbon atoms
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Detailed explanation-1: -The initiation of DNA replication occurs in two steps. First, a so-called initiator protein unwinds a short stretch of the DNA double helix. Then, a protein known as helicase attaches to and breaks apart the hydrogen bonds between the bases on the DNA strands, thereby pulling apart the two strands.
Detailed explanation-2: -The order of enzymes in DNA replication include the following: DNA helicase, RNA primase, DNA polymerase, and finally DNA ligase. During the process of DNA replication, the double helix unwinds with the help of the enzyme DNA helicase.
Detailed explanation-3: -Primers are required because DNA polymerases, the enzymes responsible for the actual addition of nucleotides to the new DNA strand, can only add deoxyribonucleotides to the 3’-OH group of an existing chain and cannot begin synthesis de novo.
Detailed explanation-4: -Step 1: Replication Fork Formation. Before DNA can be replicated, the double stranded molecule must be “unzipped” into two single strands. Step 2: Primer Binding. The leading strand is the simplest to replicate. Step 3: Elongation. Step 4: Termination. 07-Oct-2019