Question

Arrange the following disease causing agents in order of their discovery
(A). Yersinia pestis (Plague)
(B). Salmonella typhi (Typhoid fever)
(C). Treponema pallidium (Syphilis)
(D). Clostridium tetani (Tetanus)
Choose the correct answer from the options given below:

• A. (A), (B), (C), (D).
• B. (A), (C), (B), (D).
• C. (B), (D), (A), (C).
• D. (C), (B), (D), (A).

Hint:

The late 1800s was a period of intense discovery for bacteriology, thanks to the work of pioneers like Koch and Pasteur. Most major bacterial pathogens for diseases known since antiquity were identified during this time.

Answer 1

The Correct Option is C

Step 1: Understand the Task:
The task is to order the listed pathogenic bacteria based on when they were discovered. This assesses knowledge of microbiology history, specifically the late 19th and early 20th centuries ("Golden Age").

Step 2: Breakdown:
Here's the discovery timeline for each bacterium:
\[\begin{array}{rl} \bullet & \text{(B) Salmonella typhi: Identified by Karl Joseph Eberth in 1880, causing typhoid fever. } \\ \bullet & \text{(D) Clostridium tetani: Arthur Nicolaier isolated this, the cause of tetanus, from soil in 1884. } \\ \bullet & \text{(A) Yersinia pestis: Alexandre Yersin discovered this plague-causing bacterium in 1894 during the Hong Kong plague outbreak. } \\ \bullet & \text{(C) Treponema pallidum: Fritz Schaudinn and Erich Hoffmann identified this spirochete, the cause of syphilis, in 1905. } \\ \end{array}\] The chronological order is: *Salmonella typhi* (1880), *Clostridium tetani* (1884), *Yersinia pestis* (1894), and *Treponema pallidum* (1905).

Step 3: Answer:
The correct discovery order is (B), (D), (A), (C).