Q35 (CDS-II/2006) Science & Technology › Biotechnology & Health › Vaccines and immunization Answer Verified

Assertion (A) : Syphilis can be prevented by vaccination. Reason (R) : Vaccinat ion trigger s the production of antibodies in the body.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true

Result

Your answer: — · Correct: D

Explanation

Assertion (A) is false because there is currently no vaccine available for syphilis [t1, t2, t5]. Syphilis is caused by the spirochete Treponema pallidum, and while research has been ongoing since 1912, no immunization experiment has yet yielded an effective vaccine for human use [t6, t8]. Development is hindered by the pathogen's complex immune evasion mechanisms and the difficulty of identifying surface-exposed antigens [t7, t10]. Reason (R) is true as a general biological principle; vaccination works by introducing weakened or inactive pathogens (or parts of them) to trigger the body's immune system to produce specific antibodies and memory cells [c1, c2]. This process prepares the immune system to recognize and fight the actual pathogen in the future. Since the assertion is false and the reason is a true statement about vaccine mechanisms, option 4 is the correct choice.

Sources

[1] https://pmc.ncbi.nlm.nih.gov/articles/PMC6089657/
[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC5513191/
[3] https://www.sciencedirect.com/science/article/pii/S0264410X25007030
[4] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 3: Health: The Ultimate Treasure > Application > p. 39

How others answered

Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.

Community Performance

Out of everyone who attempted this question.

50%

got it right

Question map

Assertion (A) : Syphilis can be prevented by vaccination. Reason (R) : Vaccinat ion trigger s the production of antibodies in the body.

Explanation

SIMILAR QUESTIONS

Assertion (A) : There was an increase in industrial production during 1999-2000. Reason (R) : The period witnessed a stable exchange rate and improved business sentiments.

Assertion (A) : An iron ball floats on mercury but gets immersed in water. Reason (R) : The specific gravity of iron is more than that of mercury.

Assertion (A) : Human diet should compulsorily contain Glycrine, Serine and Tyrosin. Reason (R) : Essential amino acids cannot be synthesised in the human body.

Assertion (A) : Amoeba is reproduced by fission. Reason (R) : All unicellular organisms are reproduced by asexual methods.