Which is the fertility indicator that gives the approximate magnitude of completed family size?
Q22
Consider the following demographic parameters :
1. Average number of daughters born to a woman
2. Sum of age-specific fertility rates
3. Magnitude of completed family size
Which of the above parameters reflect/reflects total fertility rate?
Q23
The larvae of which one of the following mosquitoes cannot successfully be killed by spreading oil on the surface of its breeding water sources?
Q24
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
UPSC-CMS 2010 - Community Medicine UPSC-CMS Practice Questions and MCQs
Question 21: Which is the fertility indicator that gives the approximate magnitude of completed family size?
A. Age-specific Fertility Rate
B. Total Fertility Rate (Correct Answer)
C. General Fertility Rate
D. Gross Reproduction Rate
Explanation: ***Total Fertility Rate***
- The **Total Fertility Rate (TFR)** estimates the average number of children a woman would have over her lifetime if she were to experience current age-specific fertility rates.
- It provides a measure of the **completed family size** in a hypothetical cohort of women.
*Age-specific Fertility Rate*
- The **Age-specific Fertility Rate (ASFR)** measures the number of births to women in a particular age group per 1,000 women in that age group.
- It does not directly provide the completed family size but is a component used to calculate the TFR.
*General Fertility Rate*
- The **General Fertility Rate (GFR)** calculates the number of live births per 1,000 women of childbearing age (typically 15-49 years) in a given year.
- While it reflects overall fertility, it does not provide an estimate of the completed family size per woman.
*Gross Reproduction Rate*
- The **Gross Reproduction Rate (GRR)** is similar to the TFR but only considers female births.
- It estimates the average number of daughters a woman would have over her lifetime based on current age-specific fertility rates, without accounting for mortality.
Question 22: Consider the following demographic parameters :
1. Average number of daughters born to a woman
2. Sum of age-specific fertility rates
3. Magnitude of completed family size
Which of the above parameters reflect/reflects total fertility rate?
A. 1 only
B. 2 and 3 (Correct Answer)
C. 1 and 3
D. 3 only
Explanation: ***2 and 3***
- The **total fertility rate (TFR)** is precisely defined as the **sum of age-specific fertility rates (ASFR)** across all reproductive age groups (15-49 years), representing the average number of children a woman would bear if she experienced current age-specific fertility rates throughout her reproductive life.
- TFR conceptually indicates the **magnitude of completed family size** under current fertility conditions, though technically TFR is a period (synthetic cohort) measure while completed family size is an observed cohort measure.
- Parameter 2 is the **direct definition**, while parameter 3 represents the **conceptual interpretation** of what TFR indicates.
*1 only*
- The "average number of daughters born to a woman" represents the **Gross Reproduction Rate (GRR)**, not TFR.
- GRR = TFR × proportion of female births (approximately 0.49).
- **TFR includes all live births** regardless of sex, making this parameter incorrect for TFR.
*1 and 3*
- Parameter 1 represents GRR, not TFR, making this combination incorrect.
- Including an incorrect parameter invalidates this option despite parameter 3 having conceptual relevance.
*3 only*
- While completed family size has conceptual relationship to TFR, this option omits parameter 2, which is the **primary and precise definition** of TFR.
- TFR is calculated as the sum of ASFRs, not measured from actual completed families, making this incomplete.
Question 23: The larvae of which one of the following mosquitoes cannot successfully be killed by spreading oil on the surface of its breeding water sources?
A. Aedes
B. Culex
C. Mansonoides (Correct Answer)
D. Anopheles
Explanation: ***Mansonoides***
- The larvae of *Mansonoides* mosquitoes attach to the underwater stems and roots of **aquatic vegetation** for oxygen.
- This adaptation means they do not surface to breathe, rendering **surface oiling ineffective** against them.
*Aedes*
- *Aedes* larvae are **surface breathers**, obtaining oxygen from the air-water interface.
- Oiling the water surface forms a film that **prevents oxygen uptake**, suffocating the larvae.
*Culex*
- *Culex* larvae are also **surface breathers** and, like *Aedes*, rely on the air-water interface for oxygen.
- An oil film on the water surface will **block their access to atmospheric oxygen**, leading to their demise.
*Anopheles*
- *Anopheles* larvae are **surface dwellers** that lie parallel to the water surface, using their **spiracles** to breathe air.
- An oil layer effectively **obstructs these spiracles**, preventing respiration and killing the larvae.
Question 24: 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. A→4 B→1 C→3 D→2
B. A→1 B→2 C→3 D→4
C. A→2 B→4 C→1 D→3
D. A→3 B→1 C→2 D→4 (Correct Answer)
Explanation: ***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.