Govt. Exams
Entrance Exams
dNTPs (dATP, dGTP, dCTP, dTTP) are incorporated into the growing DNA strand by Taq polymerase via phosphodiester bond formation.
Each PCR cycle doubles the DNA amount (exponential amplification). After 30 cycles, theoretical amplification = 2^30 ≈ 10^9 fold increase.
Denaturation occurs at 94-95°C where hydrogen bonds between complementary DNA strands break, separating double-stranded DNA into single strands.
Taq polymerase, derived from Thermus aquaticus, is a heat-stable DNA polymerase that extends primers during PCR elongation at 72°C.
dNTPs (deoxynucleotide triphosphates) are the precursor molecules that DNA polymerase incorporates into the growing DNA strand during the extension phase of PCR.
DNA denaturation in PCR occurs at 94-95°C (or sometimes 98°C), where hydrogen bonds between DNA strands are broken, separating the double helix into single strands.
Taq polymerase, isolated from Thermus aquaticus, is the most widely used enzyme in PCR due to its heat stability and ability to synthesize DNA at high temperatures.
The annealing temperature typically ranges from 45-65°C and depends on the Tm (melting temperature) of the primers used. This temperature allows primers to bind specifically to target DNA.
WES captures and sequences exonic regions (~50 Mb) using targeted enrichment, reducing sequencing depth and cost while identifying 85-90% of disease-causing variants.
SYBR Green intercalates into double-stranded DNA and fluoresces. It is cost-effective and widely used in qPCR for gene expression studies and viral load detection.
