Q.41 Given below are two statements :
Statement IRecombinant vaccine for hepatitis B is tle first synthetic
vaccine for public use.
Statement IIHepatitis B vaccine is a DNA vaccine.
In the light of the above statements, choose the correct answer from the options
given below •
1.Both Statement I and Statement II are true
2.Both Statement I and Statement II are false
3.Statement I is true but Statement II is false
4.Statement I is false but Statement II is true
Here’s a SEO-friendly article tailored for biology students, exam prep, and science enthusiasts searching for accurate info on hepatitis B vaccines.
Hepatitis B vaccines often trip up students in exams like NEET or CSIR NET. This MCQ tests your grasp of vaccine technology—recombinant vs. DNA vaccines. Let’s break down the statements, evaluate all options, and reveal the correct answer with evidence.
The Two Statements Analyzed
Statement I: Recombinant vaccine for hepatitis B is the first synthetic vaccine for public use.
Recombinant vaccines use yeast or bacteria to produce viral proteins (antigens). The hepatitis B vaccine, approved in 1986 (e.g., Recombivax HB by Merck), was the first recombinant vaccine licensed for humans. It produces HBsAg (hepatitis B surface antigen) via recombinant DNA in Saccharomyces cerevisiae yeast.
Was it the “first synthetic vaccine”? Yes—”synthetic” here means lab-produced via genetic engineering, not from blood plasma (like earlier Hep B shots, risky due to HIV/hepatitis contamination). It marked the dawn of safe, scalable recombinant tech for public use. Statement I is true.
Statement II: Hepatitis B vaccine is a DNA vaccine.
DNA vaccines inject plasmid DNA encoding antigens, triggering cells to produce them and spark immunity. Examples include experimental Zika or COVID candidates.
Standard hepatitis B vaccines are not DNA vaccines—they deliver pre-made HBsAg protein particles, not DNA. No licensed Hep B vaccine uses naked DNA. Statement II is false.
Correct Answer: Option 3
Statement I is true but Statement II is false.
This matches real-world facts: Recombinant Hep B vaccine pioneered synthetic production (1986), while DNA vaccines remain mostly investigational.
Why Other Options Fail
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Option 1 (Both true): Wrong—Statement II fails; Hep B isn’t DNA-based.
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Option 2 (Both false): Wrong—Statement I holds; it is the first recombinant/synthetic for public use.
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Option 4 (I false, II true): Wrong on both counts.
| Option | Statement I | Statement II | Correct? | Why? |
|---|---|---|---|---|
| 1 | True | True | No | II is false (not DNA) |
| 2 | False | False | No | I is true (first recombinant) |
| 3 | True | False | Yes | Matches facts |
| 4 | False | True | No | Both reversed |
Quick Biotech Context
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Pre-1986 Hep B vaccines: Plasma-derived (risky).
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Recombinant era: Safer, cheaper; now WHO-recommended for newborns.
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DNA vaccines today: Still not standard for Hep B—trials focus on other diseases.
Nail this for your next exam! Source: CDC, WHO vaccine timelines.
