CELL STRUCTURES AND FUNCTION
CELL DIVISION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Separating the two strands of the double helices
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Preventing double helices from over-winding and breaking by relieving tension
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Adding primers to template parent strands
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Synthesizing complementary daughter strands from template parent strands
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Detailed explanation-1: -Primase is the enzyme that synthesizes RNA primers. Primers are oligonucleotides that are complementarily bound to a DNA template and from which DNA polymerases elongate. Special proteins are responsible for loading primase at the origin of replication so that leading strand DNA synthesis can commence.
Detailed explanation-2: -DNA primases are enzymes whose continual activity is required at the DNA replication fork. They catalyze the synthesis of short RNA molecules used as primers for DNA polymerases. Primers are synthesized from ribonucleoside triphosphates and are four to fifteen nucleotides long.
Detailed explanation-3: -Primase functions by synthesizing short RNA sequences that are complementary to a single-stranded piece of DNA, which serves as its template. It is critical that primers are synthesized by primase before DNA replication can occur.
Detailed explanation-4: -Primer synthesis marks the beginning of the actual synthesis of the new DNA molecule. Primers are short stretches of nucleotides (about 10 to 12 bases in length) synthesized by an RNA polymerase enzyme called primase.
Detailed explanation-5: -An RNA primer is a short segment of single-stranded RNA used as a binding site for DNA polymerase to initiate DNA replication. DNA polymerase is only able to add nucleotides to an existing nucleotide chain; it cannot “start from scratch, ” and therefore needs the RNA primer to start the process.