Biochemistry
1 questionsMajor source of vitamin K1 is:
UPSC-CMS 2020 - Biochemistry UPSC-CMS Practice Questions and MCQs
Question 81: Major source of vitamin K1 is:
- A. Fresh dark green vegetables (Correct Answer)
- B. Citrus fruits
- C. Exposure of body to sunlight
- D. Foods rich in polyunsaturated fatty acids
Explanation: ***Fresh dark green vegetables*** - **Phylloquinone (Vitamin K1)** is predominantly found in plants, particularly in **green leafy vegetables** such as kale, spinach, collard greens, and broccoli. - These vegetables are essential for providing the dietary form of vitamin K, which plays a crucial role in **blood clotting** and **bone metabolism**. *Citrus fruits* - Citrus fruits are well-known for being rich in **Vitamin C**, an essential antioxidant. - They are not a significant source of **Vitamin K1**. *Exposure of body to sunlight* - Exposure to sunlight is the primary natural mechanism for the body to synthesize **Vitamin D**. - Sunlight exposure does not contribute to the production or absorption of **Vitamin K**. *Foods rich in polyunsaturated fatty acids* - Foods rich in polyunsaturated fatty acids (PUFAs) include various vegetable oils, nuts, and fatty fish. - While important for overall health, PUFAs are not primary sources of **Vitamin K1**, although some oils may contain small amounts.
Community Medicine
7 questionsWhich of the following measures can help reduce the risk of systemic hypertension? 1. Reduction in dietary intake of common salt 2. Maintaining healthy body weight 3. Increasing potassium rich foods in the diet Select the correct answer using the code given below:
Keeping biological determinants in perspective, consider the following statements: 1. Presence of a normal karyotype is the first requisite for human health 2. Genetic screening can play an important role in prevention of wide spectrum of diseases 3. If an individual is allowed to live in healthy relationship with the environment, the person's genetic potentialities can transform into phenotypic realities Which of the above statements is/are correct?
Poor hand hygiene of a mess worker in a university college mess led to Hepatitis A cases in the hostel inmates. What type of epidemic will this exposure present with? 1. Propagated 2. Common source-continuous exposure 3. Common source-point exposure Select the correct answer using the code given below:
What is the specificity of sputum microscopy in detection of Pulmonary Tuberculosis (PTB) as per the information given below?
In a cohort of 500 women attending antenatal clinic, 70 % had ultrasonography (USG). This cohort was followed up at delivery. Of the women who had USG, 70 delivered low birth weight (LBW) babies; whereas of the women, who did not undergo USG, 50 delivered LBW babies. The incidence of LBW babies among women who had USG is:
Which one of the following is NOT a function of Epidemiology?
Which one of the following is NOT a contagious disease?
UPSC-CMS 2020 - Community Medicine UPSC-CMS Practice Questions and MCQs
Question 81: Which of the following measures can help reduce the risk of systemic hypertension? 1. Reduction in dietary intake of common salt 2. Maintaining healthy body weight 3. Increasing potassium rich foods in the diet Select the correct answer using the code given below:
- A. 2 and 3 only
- B. 1 and 2 only
- C. 1, 2 and 3 (Correct Answer)
- D. 1 and 3 only
Explanation: ***1, 2 and 3*** - **Reduction in dietary intake of common salt** (sodium) is crucial as excessive sodium leads to fluid retention and increased blood volume, directly contributing to **hypertension**. WHO recommends <5g/day salt intake. - **Maintaining healthy body weight** (controlling BMI) significantly reduces the risk of hypertension, as obesity is a major independent risk factor. Even 5-10% weight loss can substantially lower blood pressure. - **Increasing potassium-rich foods** helps counteract the effects of sodium, promoting sodium excretion and relaxing blood vessel walls, thereby lowering blood pressure. Recommended intake is 3.5-5g/day. *2 and 3 only* - This option is incorrect because **reducing salt intake** (measure 1) is a fundamental and highly effective strategy for preventing and managing hypertension. - Excluding salt reduction from the recommended measures would disregard a cornerstone of cardiovascular health proven by DASH diet trials. *1 and 2 only* - This option is flawed because **increasing potassium-rich foods** (measure 3) is a recognized dietary intervention that contributes to blood pressure control. - Potassium helps counterbalance sodium effects, and its omission makes this answer incomplete. *1 and 3 only* - This option is incorrect as it excludes **maintaining healthy body weight** (measure 2), which is a critical and well-established lifestyle modification for preventing and managing hypertension. - Obesity is a significant risk factor, and weight management is essential for blood pressure control.
Question 82: Keeping biological determinants in perspective, consider the following statements: 1. Presence of a normal karyotype is the first requisite for human health 2. Genetic screening can play an important role in prevention of wide spectrum of diseases 3. If an individual is allowed to live in healthy relationship with the environment, the person's genetic potentialities can transform into phenotypic realities Which of the above statements is/are correct?
- A. 2 and 3 only (Correct Answer)
- B. 1 and 2 only
- C. 1, 2 and 3
- D. 1 and 3 only
Explanation: ***Correct: 2 and 3 only*** **Statement 2 - Genetic screening (CORRECT):** - Genetic screening is a powerful tool in preventive medicine - **Newborn screening** identifies conditions like PKU, congenital hypothyroidism, enabling early intervention - **Carrier screening** prevents diseases like thalassemia and sickle cell disease - **Predictive testing** (e.g., BRCA1/2) allows risk-based prevention strategies - Enables **primary and secondary prevention** across a wide spectrum of genetic conditions **Statement 3 - Gene-environment interaction (CORRECT):** - Fundamental principle of **genetics and public health** - An individual's genetic potential requires a **healthy environment** for optimal expression - **Phenotypic realities** emerge from the interplay between genotype and environmental factors - Supports the concept of **positive health** and health promotion - Underscores importance of favorable living conditions, nutrition, and social determinants **Statement 1 - Normal karyotype as first requisite (INCORRECT):** - This is **too absolute** and medically inaccurate - Many chromosomal variations compatible with healthy life (Turner syndrome, Klinefelter syndrome) - Severe diseases can occur despite **normal karyotype** (multifactorial diseases, acquired conditions) - Health is multifactorial - not determined by karyotype alone - Normal karyotype is favorable but not an absolute "first requisite" *Incorrect: 1 and 2 only* - Statement 1 is incorrect, invalidating this option *Incorrect: 1, 2 and 3* - Statements 2 and 3 are correct, but inclusion of incorrect statement 1 makes this option wrong *Incorrect: 1 and 3 only* - Statement 1 is incorrect, invalidating this option
Question 83: Poor hand hygiene of a mess worker in a university college mess led to Hepatitis A cases in the hostel inmates. What type of epidemic will this exposure present with? 1. Propagated 2. Common source-continuous exposure 3. Common source-point exposure Select the correct answer using the code given below:
- A. 1 only
- B. 1 and 3
- C. 2 only (Correct Answer)
- D. 1 and 2
Explanation: ***2 only*** - A mess worker with **ongoing poor hand hygiene** represents a **continuous common source exposure**. The worker continues to handle food over days or weeks with persistent poor hygiene, leading to **repeated contamination** and cases occurring over an extended period rather than clustered around a single incubation period. This produces a plateau-like epidemic curve characteristic of continuous exposure. *1 only* - **Propagated epidemic** occurs through **person-to-person transmission** (e.g., measles, chickenpox), where each case can generate new cases, creating successive waves with progressively larger peaks. Hepatitis A from a food handler is a **common source outbreak**, not propagated, as cases trace back to contaminated food rather than spreading between inmates. *1 and 3* - Option 1 (propagated) is incorrect as explained above. Option 3 (**common source-point exposure**) would apply if there was a **single, brief contamination event** (e.g., one contaminated meal), resulting in cases appearing within one incubation period with a sharp peak. The scenario describes **persistent poor hygiene** suggesting ongoing contamination, not a single point event. *1 and 2* - Option 1 (propagated) is incorrect as this is a common source outbreak from contaminated food, not person-to-person transmission.
Question 84: What is the specificity of sputum microscopy in detection of Pulmonary Tuberculosis (PTB) as per the information given below?
- A. 94 %
- B. 10 %
- C. 90 % (Correct Answer)
- D. 36 %
Explanation: ***90 %*** - Specificity is calculated as the number of **true negatives** divided by the sum of true negatives and **false positives**. - From the table: True Negatives = 180 (PTB Absent, Sputum Negative) and False Positives = 20 (PTB Absent, Sputum Positive). - Specificity = (180 / (180 + 20)) × 100 = (180 / 200) × 100 = **90%**. - This represents the ability of the test to correctly identify those **without the disease**. *36 %* - This value does not correspond to any standard diagnostic test metric such as sensitivity, specificity, positive predictive value, or negative predictive value based on the provided data. - It might be a miscalculation or a different ratio not typically used in this context. *94 %* - This value does not match any standard calculation from the given 2×2 table. - It may represent a misinterpretation of the data or an incorrect calculation. *10 %* - This value represents the **false positive rate** (1 - specificity). - Calculated as: False Positives / Total without disease = 20 / 200 = 10%. - It is the complement of specificity, not specificity itself.
Question 85: In a cohort of 500 women attending antenatal clinic, 70 % had ultrasonography (USG). This cohort was followed up at delivery. Of the women who had USG, 70 delivered low birth weight (LBW) babies; whereas of the women, who did not undergo USG, 50 delivered LBW babies. The incidence of LBW babies among women who had USG is:
- A. 25 %
- B. 10 %
- C. 20 % (Correct Answer)
- D. 15 %
Explanation: ***20 %*** - Total women are 500, and 70% had USG, which equals 350 women. - Of these 350 women, 70 delivered **low birth weight (LBW)** babies. Therefore, the incidence is (70/350) * 100% = **20%**. *25 %* - This option would imply a higher number of LBW babies among those who had USG than the actual data. - It does not align with the calculation based on the given figures (70 LBW babies out of 350 women who had USG). *10 %* - This option represents a lower incidence and does not correspond to the calculation of (70/350) * 100%. - This value might be obtained if the total number of women with USG was incorrectly assumed to be 700. *15 %* - This option is incorrect as it does not match the calculated incidence of LBW babies among women who underwent USG. - This would mean only 52.5 LBW babies were born, which contradicts the information given that 70 delivered LBW babies.
Question 86: Which one of the following is NOT a function of Epidemiology?
- A. Searching for the causes and risk factors
- B. Identifying syndromes
- C. To study historically the rise and fall of disease in the population
- D. Making a clinical diagnosis (Correct Answer)
Explanation: ***Making a clinical diagnosis*** - **Epidemiology** focuses on **population-level health patterns** and determinants of disease, not individual patient diagnosis. - Making a **clinical diagnosis** is the role of a healthcare provider based on a patient's symptoms, physical examination, and diagnostic tests. *Searching for the causes and risk factors* - A primary function of epidemiology is to **identify potential causes** and **risk factors** for diseases within populations. - This involves investigating associations between **exposures** and **health outcomes**. *Identifying syndromes* - Epidemiologists help identify new or unrecognized **patterns of disease** presentation that may constitute a **syndrome**. - This involves observing **clusters of symptoms** or conditions in a population. *To study historically the rise and fall of disease in the population* - **Historical epidemiology** tracks changes in disease incidence, prevalence, and mortality over time. - This function helps understand disease trends and the **impact of public health interventions**.
Question 87: Which one of the following is NOT a contagious disease?
- A. Malaria (Correct Answer)
- B. Trachoma
- C. Leprosy
- D. Scabies
Explanation: ***Malaria*** - Malaria is caused by **Plasmodium parasites** transmitted through the bite of infected Anopheles mosquitoes. It is not spread directly from person to person. - Transmission requires a **vector** (mosquito), making it a non-contagious infectious disease. *Trachoma* - Trachoma is a contagious bacterial infection caused by **Chlamydia trachomatis**, spread through direct contact with eye and nose discharge of an infected person. - It can also be transmitted via **fomites** like contaminated towels or clothing, or through eye-seeking flies. *Leprosy* - Leprosy, caused by **Mycobacterium leprae**, is a chronic infectious disease that is considered contagious, although with low infectivity. - It is primarily transmitted through **nasal droplets** during close and prolonged contact with an untreated infected person. *Scabies* - Scabies is a contagious skin infestation caused by the **mite Sarcoptes scabiei**, which burrows into the outer layer of the skin. - It is easily spread through **direct, prolonged skin-to-skin contact** with an infected person.
Microbiology
2 questionsWhich of the following represent the properties of an ideal disinfectant? 1. It is broad spectrum 2. It is fast acting 3. It is non-toxic Select the correct answer using the code given below:
During the EARLY phase of a primary immune response, which of the following best describes the relationship between peak IgM and IgG antibody levels?
UPSC-CMS 2020 - Microbiology UPSC-CMS Practice Questions and MCQs
Question 81: Which of the following represent the properties of an ideal disinfectant? 1. It is broad spectrum 2. It is fast acting 3. It is non-toxic Select the correct answer using the code given below:
- A. 1 and 3 only
- B. 1, 2 and 3 (Correct Answer)
- C. 2 and 3 only
- D. 1 and 2 only
Explanation: ***Correct Answer: 1, 2 and 3*** An **ideal disinfectant** should possess all three properties: - **Broad spectrum activity** - It should effectively kill or inactivate a wide range of microorganisms, including bacteria, viruses, fungi, and spores - **Fast-acting** - It should achieve rapid antimicrobial effect after application, which is crucial in clinical settings to prevent pathogen spread and minimize exposure time - **Non-toxic** - It should be safe for humans and animals when used as directed, minimizing adverse effects on users, patients, and the environment Additional desirable properties include stability, solubility in water, non-corrosive nature, pleasant odor, and cost-effectiveness. *Incorrect: 1 and 3 only* - While broad spectrum and non-toxic nature are crucial, **fast action** is also an essential property for an ideal disinfectant to ensure rapid microbial elimination - A disinfectant that is not fast-acting would be less practical in situations requiring quick decontamination *Incorrect: 2 and 3 only* - A disinfectant that is fast-acting and non-toxic is insufficient without **broad-spectrum activity** - Without broad-spectrum activity, it may fail to eliminate certain pathogens, limiting its overall utility in infection control *Incorrect: 1 and 2 only* - Although broad spectrum and fast-acting properties are important, an ideal disinfectant must also be **non-toxic** - Toxicity would severely limit its application, especially in healthcare settings where human contact is frequent
Question 82: During the EARLY phase of a primary immune response, which of the following best describes the relationship between peak IgM and IgG antibody levels?
- A. 50 times more
- B. 100 times more (Correct Answer)
- C. 25 times more
- D. 10 times more
Explanation: ***100 times more*** - In the **early phase of a primary immune response**, **IgM** is the first antibody produced and reaches peak levels when **IgG** levels are still very low. - During this early period (approximately days 5-10), the **IgM concentration** can be significantly higher than IgG, with some references citing ratios up to 100-fold. - **Important note:** As the primary response matures, **IgG levels rise and eventually exceed IgM levels** through class switching. This question specifically addresses the early peak comparison. *50 times more* - While IgM does predominate early in the primary response, the 50-fold ratio underestimates the typical difference during the **early peak phase** when IgG production has just begun. - The most commonly cited ratio for early primary response is closer to 100-fold. *25 times more* - This ratio **underestimates** the relative abundance of **IgM** compared to **IgG** during the early peak of a primary immune response. - **IgG** levels are typically very low or just beginning to rise in the early stages, while IgM has reached peak levels. *10 times more* - This significantly **underestimates** the difference in antibody levels during the early primary immune response. - The rapid and robust initial production of **IgM** with delayed IgG production creates a much larger differential in the early phase. **Clinical Note:** In a **secondary immune response**, the pattern reverses dramatically—IgG is produced rapidly and in much higher quantities than IgM (often 100-1000 times more) due to memory B cell activation.