Question

Now-a-days, the early diagnosis of bacterial or viral infection in humans is possible using

• A. Serum analyser
• B. DNA sequencer
• C. PCR
• D. CT Scan

Answer 1

The Correct Option is C

Polymerase Chain Reaction (PCR) is a cornerstone of modern diagnostics due to its ability to amplify trace amounts of bacterial or viral DNA/RNA, enabling early detection even before symptoms appear. 

Unlike serum analyzers (A), which detect antibodies or metabolites, or CT scans (D), which visualize structural changes, PCR identifies the pathogen’s genetic material directly. DNA sequencers (B) are used for detailed genomic analysis but are less practical for rapid diagnostics. 

PCR’s sensitivity and specificity make it indispensable for detecting infections like COVID-19, HIV, and tuberculosis.

The correct answer is (C) PCR.

Answer 2

PCR amplifies pathogen DNA/RNA for sensitive detection (e.g., COVID-19, TB).

PCR stands for Polymerase Chain Reaction. It is a laboratory technique used to amplify and replicate specific segments of DNA. The process allows scientists to create millions of copies of a particular DNA sequence, enabling detailed analysis even from small DNA samples. PCR is widely used in molecular biology for a variety of purposes, such as:

DNA Cloning: Making copies of a gene or DNA fragment for further study or manipulation.

Medical Diagnostics: Detecting diseases caused by specific pathogens, like the detection of HIV or SARS-CoV-2 (COVID-19).

Other tools:

• (A) Serum analyzer: Detects antibodies (delayed response).
• (B) DNA sequencer: Identifies mutations (not rapid).
• (D) CT scan: Visualizes tissue damage (not molecular).

Correct Answer: (C) PCR