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.
Ophthalmology
4 questionsIrregular pupil is seen in which of the following conditions?
How is dioptric power related to focal length?
What is the definition of the visual axis in relation to the eye?
Which of the following is a known complication of vernal keratoconjunctivitis?
NEET-PG 2012 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 751: Irregular pupil is seen in which of the following conditions?
- A. Glaucoma
- B. Trauma (Correct Answer)
- C. Retinal detachment
- D. Oculomotor palsy
Explanation: ***Trauma*** - **Direct injury to the iris** can cause tears or distortion, leading to an **irregularly shaped pupil** - Results in conditions like **traumatic mydriasis** (dilated pupil) or **iridodialysis** (iris detachment from its root at the ciliary body) - **Sphincter pupillae tears** cause characteristic irregularity with notching or peaked appearance *Glaucoma* - Primarily characterized by **optic nerve damage** due to increased intraocular pressure - In acute angle closure glaucoma, pupil may be **mid-dilated and fixed**, but remains **round**, not irregular - Pupil shape irregularity is not a feature of chronic glaucoma *Retinal detachment* - Involves **separation of the neurosensory retina** from the underlying retinal pigment epithelium - This is a **posterior segment pathology** that does not affect anterior segment structures - **Pupil shape remains regular** despite severe vision loss *Oculomotor palsy* - Affects the **third cranial nerve (CN III)**, leading to ptosis, strabismus, and loss of parasympathetic innervation - Pupil is typically **dilated and fixed** due to unopposed sympathetic action - Pupil remains **round but unresponsive to light**, not irregular in shape
Question 752: 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.
Question 753: What is the definition of the visual axis in relation to the eye?
- A. Line from the object to the fovea (Correct Answer)
- B. Line from the center of the lens to the cornea
- C. Line from the center of the cornea to the center of the lens
- D. None of the options
Explanation: ***Line from the object to the fovea*** - The **visual axis** is the theoretical line connecting the **object of regard** in the external world to the **fovea centralis** (the area of sharpest vision) on the retina. - This axis passes through the **nodal points** of the eye, which are conceptual points within the lens system acting as optical centers. *Line from the center of the lens to the cornea* - This description does not correspond to any standard anatomical or optical axis of the eye. - The **cornea** and **lens** are parts of the eye's refracting system, but a line solely between their centers would not define visual perception. *Line from the center of the cornea to the center of the lens* - This line is generally referred to as the **optical axis**, which is an anatomical reference line. - The optical axis typically passes through the centers of curvature of the refractive surfaces, but it does not necessarily align with the actual line of sight or the path of light from an object to the fovea. *None of the options* - This option is incorrect because the first option accurately defines the visual axis.
Question 754: Which of the following is a known complication of vernal keratoconjunctivitis?
- A. Keratoconus (Correct Answer)
- B. Retinal detachment
- C. Vitreous hemorrhage
- D. Cataract
Explanation: ***Keratoconus*** - **Vernal keratoconjunctivitis (VKC)** is a chronic allergic eye condition associated with persistent eye rubbing, which can lead to thinning and bulging of the cornea, a condition known as **keratoconus**. - Long-term inflammation and mechanical stress from allergic reactions and *eye rubbing* contribute to the corneal structural changes seen in keratoconus. - This is the **most common and well-recognized complication** of VKC. *Cataract* - While cataracts can occur in VKC patients (particularly from **chronic topical steroid use** or severe disease with shield ulcers), they are **less common than keratoconus** as a direct complication. - Keratoconus remains the more characteristic and frequently encountered complication specifically associated with the mechanical trauma of eye rubbing in VKC. *Retinal detachment* - **Retinal detachment** is a condition where the retina separates from its underlying support tissues and is typically associated with trauma, high myopia, or diabetic retinopathy, not VKC. - VKC primarily affects the conjunctiva and cornea, and its inflammatory processes do not directly cause retinal detachment. *Vitreous hemorrhage* - **Vitreous hemorrhage** involves bleeding into the gel-like substance that fills the eye and is commonly caused by conditions like diabetic retinopathy or retinal tears, not VKC. - VKC does not involve the posterior segment of the eye in a way that would lead to vitreous hemorrhage.
Pharmacology
1 questionsWhich antilipidemic drug reduces cholesterol levels by inhibiting cholesterol absorption?
NEET-PG 2012 - Pharmacology NEET-PG Practice Questions and MCQs
Question 751: Which antilipidemic drug reduces cholesterol levels by inhibiting cholesterol absorption?
- A. Ezetimibe (Correct Answer)
- B. Orlistat
- C. Cholestyramine
- D. Statins
Explanation: ***Ezetimibe*** - **Ezetimibe** selectively inhibits the **Niemann-Pick C1-Like 1 (NPC1L1) protein**, which is responsible for plant sterol and cholesterol absorption in the small intestine. - This action leads to a reduction in **LDL-C** levels by decreasing the amount of cholesterol available to the liver. *Orlistat* - **Orlistat** is a **lipase inhibitor** that prevents the absorption of dietary fats by inhibiting gastric and pancreatic lipases. - While it aids in weight loss and can indirectly improve lipid profiles, its primary mechanism is *not* direct inhibition of cholesterol absorption. *Cholestyramine* - **Cholestyramine** is a **bile acid sequestrant** that binds to bile acids in the intestine, preventing their reabsorption. - This increases the excretion of bile acids, prompting the liver to synthesize more bile acids from cholesterol, thereby lowering cholesterol levels, but it does *not* directly inhibit cholesterol absorption. *Statins* - **Statins** (HMG-CoA reductase inhibitors) are considered first-line agents for lowering cholesterol by inhibiting the **rate-limiting step in cholesterol synthesis** in the liver. - Their primary action is to reduce endogenous cholesterol production, not to block cholesterol absorption from the gut.