UPSC-CMS 2010 Practice Questions

Q: Match List-I with List-II and select the correct answer using the code given below the Lists: List-I (Vectors): A. Hard ticks B. Sandflies C. Louse D. Soft ticks List-II (Diseases): 1. Oriental sore 2. Epidemic typhus 3. Tularemia 4. Relapsing fever

A→3 B→1 C→2 D→4. ***A→3 B→1 C→2 D→4*** - **Hard ticks** (A) are primary vectors for **tularemia** (3), transmitting *Francisella tularensis* through their bite during blood feeding. - **Sandflies** (B) transmit **oriental sore** (1), the cutaneous form of **leishmaniasis** caused by *Leishmania tropica* and other species. *A→4 B→1 C→3 D→2* - Incorrectly matches **hard ticks** with **relapsing fever**, which is specifically transmitted by **soft ticks** (*Ornithodoros* species). - Misassociates **louse** with **tularemia**, when **body lice** are established vectors for **epidemic typhus**. *A→1 B→2 C→3 D→4* - Wrongly pairs **hard ticks** with **oriental sore**, which requires **sandfly** vectors for transmission of *Leishmania* parasites. - Incorrectly matches **sandflies** with **epidemic typhus**, a louse-borne disease caused by *Rickettsia prowazekii*. *A→2 B→4 C→1 D→3* - Mismatches **hard ticks** with **epidemic typhus**, which is transmitted by **body lice**, not tick species. - Incorrectly associates **soft ticks** with **tularemia**, when they are specific vectors for **relapsing fever** caused by *Borrelia* species.

Q: Which of the following is the least toxic organophosphorus compound?

Abate. ***Abate (Temephos)*** - **Abate** is specifically designed for use in water as a mosquito larvicide and has a notably **lower mammalian toxicity** compared to other organophosphates. - Its chemical structure and metabolic breakdown in mammals make it less potent in inhibiting **acetylcholinesterase**. *Malathion* - While generally considered less toxic than some other organophosphates like parathion, **malathion** still poses significant toxicity, especially with **high or prolonged exposure**. - It is metabolically activated to **malaoxon**, a more potent acetylcholinesterase inhibitor. *Fenitrothion* - **Fenitrothion** is an organophosphate insecticide with moderate to high toxicity, similar to malathion, but often considered more toxic for some species. - It works by inhibiting **cholinesterase enzymes**, leading to a buildup of acetylcholine. *Parathion* - **Parathion** is one of the most highly toxic organophosphorus compounds, historically used as a powerful insecticide but now restricted or banned in many countries due to its severe toxicity. - It is readily absorbed and metabolically converted to **paraoxon**, a very potent cholinesterase inhibitor.

Question 1

Match List-I with List-II and select the correct answer using the code given below the Lists:

List-I (Vectors):
A. Hard ticks
B. Sandflies
C. Louse
D. Soft ticks

List-II (Diseases):
1. Oriental sore
2. Epidemic typhus
3. Tularemia
4. Relapsing fever

Accepted Answer

A→3  B→1  C→2  D→4

Answer

A→4  B→1  C→3  D→2

Answer

A→1  B→2  C→3  D→4

Answer

A→2  B→4  C→1  D→3

Question 2

Which of the following is the least toxic organophosphorus compound?

Accepted Answer

Abate

Answer

Parathion

Answer

Malathion

Answer

Fenitrothion

UPSC-CMS 2010

Community Medicine

Forensic Medicine