Community Medicine
5 questionsWhich of the following is not a source of environmental radiation?
What is the recommended amount of bleaching powder necessary to disinfect stools contaminated with cholera?
Which of the following is not considered an occupational cancer?
At what level is Kit B (basic emergency obstetric care supplies/ASHA kit/immunization supplies) provided in the healthcare system?
What is the statistical term for the value that occurs most frequently in a data set?
NEET-PG 2012 - Community Medicine NEET-PG Practice Questions and MCQs
Question 751: Which of the following is not a source of environmental radiation?
- A. Uranium
- B. Radon
- C. CO (Correct Answer)
- D. Radium
Explanation: ***CO*** - **Carbon monoxide (CO)** is a toxic gas produced by incomplete combustion, but it is **not radioactive** and thus not a source of environmental radiation. - Its danger comes from its ability to bind to **hemoglobin**, preventing oxygen transport, not from emitting radiation. *Radium* - **Radium** is a highly **radioactive element** found naturally in the environment as a decay product of uranium and thorium. - It emits **alpha and gamma radiation**, contributing significantly to natural background radiation. *Uranium* - **Uranium** is a naturally occurring **radioactive element** found in rocks, soil, and water. - It decays through a series of steps, emitting **alpha, beta, and gamma radiation**, and is a primary source of environmental background radiation. *Radon* - **Radon** is a **radioactive gas** that is formed from the decay of uranium in soil and rocks. - It is a significant source of **indoor environmental radiation exposure** and a known cause of lung cancer.
Question 752: What is the recommended amount of bleaching powder necessary to disinfect stools contaminated with cholera?
- A. 50 gm/liter (Correct Answer)
- B. 75 gm/liter
- C. 90 gm/liter
- D. 100 gm/liter
Explanation: ***50 gm/liter*** - For effective disinfection of stools contaminated with cholera, a concentration of **50 gm of bleaching powder per liter** of stool is recommended to ensure the destruction of **Vibrio cholerae**. - This concentration typically provides a sufficient amount of available **chlorine** to inactivate the bacteria within a reasonable contact time. *75 gm/liter* - While this concentration would certainly disinfect, it is **higher than necessary** for routine cholera stool disinfection and leads to inefficient resource use. - Using excess bleaching powder can also create a **stronger odor** and possibly increase the risk of skin or respiratory irritation. *90 gm/liter* - This concentration is **excessive** and not the standard recommendation for cholera stool disinfection. - Higher concentrations contribute to **waste of resources** and do not offer significantly improved efficacy over the recommended dose for this specific application. *100 gm/liter* - This concentration is significantly **higher than required** for effective disinfection of cholera-contaminated stools. - Using such a high amount is **economically inefficient** and offers no additional benefit in terms of disinfection for this specific pathogen and application.
Question 753: Which of the following is not considered an occupational cancer?
- A. Lung
- B. Breast (Correct Answer)
- C. Liver
- D. Bladder
Explanation: ***Breast*** - Breast cancer has a **limited association** with occupational exposure compared to other cancers [1], mainly influenced by genetic and hormonal factors. - While some studies suggest minor correlations, the **impact of environment** and occupation is considerably less significant for breast cancer. *Bladder* - Strongly linked to **aromatic amines** from dyes and rubber manufacturing [2], as well as exposures to **chemical irritants**. - The **occupational risk** is well-documented, particularly among workers in the chemical industry [1]. *Liver* - Associated with **chemical exposures** such as aflatoxins and certain industrial solvents, particularly in the manufacturing and agriculture sectors. - Significant occupational hazards, like **vinyl chloride**, have demonstrated a clear link to liver cancer [2]. *Lung* - Closely tied to **asbestos** [1][3], **smoke**, and other pollutants, highlighting the role of industrial environments in increasing risk. - **Occupational exposure** remains a major contributor to lung cancer rates, particularly in mining and construction [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, p. 286. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 217-218. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 221-222.
Question 754: At what level is Kit B (basic emergency obstetric care supplies/ASHA kit/immunization supplies) provided in the healthcare system?
- A. PHC
- B. CHC
- C. FRU level
- D. Sub-center (Correct Answer)
Explanation: ***Sub-center*** - **Kit B** is designed for use at the **Sub-center level** within the Indian healthcare system, specifically for **ASHA workers** and other grassroots healthcare providers. - It contains essential supplies for **basic emergency obstetric care**, as well as items for **immunization** and other primary healthcare needs in the community. *PHC* - **Primary Healthcare Centers (PHCs)** are a higher level of care compared to sub-centers and typically have more extensive facilities and a wider range of services. - While PHCs do offer obstetric care and immunization, **Kit B** itself is primarily intended for the more peripheral sub-center operations. *CHC* - **Community Healthcare Centers (CHCs)** serve as referral units for 4-5 PHCs and provide specialist services, including basic surgical and obstetric care. - The level of care and supplies at a CHC is far more comprehensive than what is contained in **Kit B**, which targets basic community-level interventions. *FRU level* - **First Referral Units (FRUs)** are typically equipped to handle all obstetric emergencies, including Caesarean sections and blood transfusions. - The scope of services at an FRU is significantly advanced, requiring a much broader inventory of medical supplies and equipment than what is found in **Kit B**.
Question 755: What is the statistical term for the value that occurs most frequently in a data set?
- A. Median
- B. Mode (Correct Answer)
- C. Standard deviation
- D. Mean
Explanation: ***Mode*** - The **mode** is the value that appears most often in a set of data. - It represents the **most frequent observation** within a dataset. *Median* - The **median** is the middle value in a dataset when the values are arranged in ascending or descending order. - It is a measure of **central tendency** that is less affected by outliers than the mean. *Standard deviation* - **Standard deviation** measures the amount of variation or dispersion of a set of values. - A low standard deviation indicates that the data points tend to be **close to the mean**. *Mean* - The **mean** is the arithmetic average of a dataset, obtained by summing all values and dividing by the number of values. - It is a common measure of **central tendency** but can be influenced by extreme values.
Microbiology
1 questionsWhat is the correct sequence of the sexual cycle in malaria?
NEET-PG 2012 - Microbiology NEET-PG Practice Questions and MCQs
Question 751: What is the correct sequence of the sexual cycle in malaria?
- A. Sporozoites to gametocytes
- B. Gametocytes to gametes
- C. Gametocytes to sporozoites (Correct Answer)
- D. Gametes to zygote
Explanation: ***Gametocytes to sporozoites*** - The sexual cycle begins when a mosquito ingests **gametocytes** during a blood meal. - These gametocytes develop into **gametes**, which fuse to form a **zygote**. The zygote matures into an **oocyst** and then releases **sporozoites**, which migrate to the mosquito's salivary glands, ready to infect a new human host. *Gametocytes to gametes* - This is an initial step within the sexual cycle where gametocytes differentiate into **male and female gametes**, respectively. - However, it's not the complete *sequence* of the sexual cycle, as it omits subsequent crucial stages like fertilization and sporozoite formation. *Sporozoites to gametocytes* - **Sporozoites** are injected into a human host and initiate the asexual cycle by infecting liver cells, then red blood cells. - **Gametocytes** are formed later during the asexual cycle in the human host, ready to be picked up by another mosquito; this sequence describes part of the human infection, not the sexual cycle in the mosquito. *Gametes to zygote* - This step represents **fertilization**, where male and female gametes fuse, forming a **zygote** in the mosquito gut. - While essential, it is only one part of the overall sexual cycle and doesn't encompass the full transformation from gametocytes to infective sporozoites.
Ophthalmology
1 questionsHow is dioptric power related to focal length?
NEET-PG 2012 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 751: How is dioptric power related to focal length?
- A. Directly to square of focal length
- B. Inversely to focal length (Correct Answer)
- C. Directly to focal length
- D. Inversely to square of focal length
Explanation: ***Inversely to focal length*** - Dioptric power, measured in **diopters**, is defined as the **reciprocal of the focal length** when the focal length is expressed in meters. - This inverse relationship means that a shorter focal length corresponds to a higher dioptric power, indicating stronger light-bending ability. *Directly to square of focal length* - The relationship between dioptric power and focal length is **linear** (inverse), not squared. - There is no direct proportional relationship with the square of the focal length in optical power calculations. *Directly to focal length* - Dioptric power is **inversely proportional** to focal length, not directly proportional. - As focal length increases, the power of the lens to converge or diverge light decreases. *Inversely to square of focal length* - Dioptric power is inversely proportional to the **focal length itself**, not its square. - The square of the focal length is not typically used in defining the dioptric power of a lens.
Pharmacology
3 questionsSide effects of thiazide diuretics include all of the following except?
Which antibiotic is Actinomycosis sensitive to?
Which enzyme is irreversibly inhibited by aspirin?
NEET-PG 2012 - Pharmacology NEET-PG Practice Questions and MCQs
Question 751: Side effects of thiazide diuretics include all of the following except?
- A. Hypokalemia
- B. Erectile dysfunction
- C. Hyponatremia
- D. Hypocalcemia (Correct Answer)
Explanation: ***Hypocalcemia*** - Thiazide diuretics are known to cause **hypercalcemia** (increased calcium reabsorption), NOT hypocalcemia, due to their action on the distal convoluted tubule. - This property makes them useful in treating conditions like **idiopathic hypercalciuria** and **calcium-containing kidney stones**. - The mechanism involves enhanced passive calcium reabsorption in the proximal tubule and active reabsorption in the distal tubule. *Hyponatremia* - Thiazide diuretics impair the kidney's ability to dilute urine and reabsorb sodium in the distal tubule, leading to **increased sodium excretion** and potential hyponatremia. - This effect is more pronounced in **elderly patients** and those with increased free water intake. - Hyponatremia is one of the most common electrolyte disturbances with thiazides. *Hypokalemia* - Thiazides increase the delivery of sodium and water to the collecting duct, leading to increased activity of the **renin-angiotensin-aldosterone system** and enhanced potassium secretion. - This results in **potassium wasting** and hypokalemia, which may require potassium supplementation or combination with potassium-sparing diuretics. *Erectile dysfunction* - Thiazide diuretics can cause **erectile dysfunction** through mechanisms including effects on vascular smooth muscle, reduced blood flow, and possible hormonal effects. - This is a common side effect reported in male patients using these medications for hypertension and may affect compliance.
Question 752: Which antibiotic is Actinomycosis sensitive to?
- A. Streptomycin
- B. Nystatin
- C. Doxycycline
- D. Penicillin (Correct Answer)
Explanation: ***Penicillin*** - **Penicillin** is the **antibiotic of choice** for treating Actinomycosis due to the organism's high sensitivity. - Treatment typically involves a **long course** of high-dose penicillin for several months. *Streptomycin* - **Streptomycin** is an **aminoglycoside antibiotic** primarily used for **tuberculosis** and some gram-negative bacterial infections. - It is **not effective** against Actinomyces species. *Nystatin* - **Nystatin** is an **antifungal medication** used to treat **yeast infections**, particularly Candida. - It has **no antibacterial activity** and thus no role in treating Actinomycosis. *Doxycycline* - While **doxycycline** can be used as an **alternative** in patients allergic to penicillin, it is **not the primary choice**. - Its effectiveness is generally less pronounced than penicillin, and it's reserved for second-line treatment.
Question 753: Which enzyme is irreversibly inhibited by aspirin?
- A. Lipooxygenase
- B. Cyclooxygenase (Correct Answer)
- C. Thromboxane synthase
- D. Phospholipase
Explanation: ***Cyclooxygenase*** - **Aspirin** irreversibly inhibits **cyclooxygenase (COX-1 and COX-2)** by acetylating a serine residue in the enzyme's active site. - This irreversible inhibition prevents the production of **prostaglandins, thromboxane**, and **prostacyclin**, thereby reducing inflammation, pain, fever, and platelet aggregation. *Lipooxygenase* - **Lipooxygenase** is involved in the synthesis of **leukotrienes**, which are mediators of inflammation and allergic responses. - Aspirin does not directly inhibit lipooxygenase; rather, it primarily targets the COX pathway. *Thromboxane synthase* - **Thromboxane synthase** is an enzyme downstream of COX, responsible for converting prostaglandin H2 into **thromboxane A2**. - While aspirin's effect on platelet aggregation is due to reduced thromboxane A2 synthesis via COX inhibition, it does not directly inhibit thromboxane synthase itself. *Phospholipase* - **Phospholipase A2** is responsible for releasing **arachidonic acid** from cell membrane phospholipids, which is the initial step in both the cyclooxygenase and lipooxygenase pathways. - Aspirin does not directly inhibit phospholipase A2; its action occurs later in the cascade.