Community Medicine
5 questionsWhich of the following is not a source of environmental radiation?
Which of the following statements about the population pyramid of India is incorrect?
Which disease is associated with a propagative cycle?
What is the most common cancer diagnosed in men?
What is the caloric value of the nutritional supplement provided for a two-year-old child under the ICDS scheme?
NEET-PG 2012 - Community Medicine NEET-PG Practice Questions and MCQs
Question 581: 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 582: Which of the following statements about the population pyramid of India is incorrect?
- A. India has narrow apex
- B. Developing countries have bulge in the center
- C. India has narrow base (Correct Answer)
- D. India has broad base
Explanation: ***Correct Answer: India has narrow base*** - A **narrow base** in a population pyramid indicates a **low birth rate** and a small proportion of young people. - This statement is **INCORRECT for India**, as India's population pyramid has a **broad base** due to high birth rates and a large proportion of children and young people. - This is the correct answer because the question asks for the incorrect statement. *Incorrect Option: India has narrow apex* - A **narrow apex** signifies a **smaller proportion of older individuals**, indicating lower life expectancy. - This is TRUE for India's population pyramid, making it an incorrect answer choice. *Incorrect Option: Developing countries have bulge in the center* - A **bulge in the center** represents a larger cohort of working-age adults in developing countries undergoing demographic transition. - This reflects improvements in childhood survival and declining (but still substantial) birth rates. - This is TRUE, making it an incorrect answer choice. *Incorrect Option: India has broad base* - A **broad base** indicates a **high birth rate** and large proportion of young children in the population. - This is TRUE and characteristic of India's population structure, making it an incorrect answer choice.
Question 583: Which disease is associated with a propagative cycle?
- A. None of the options
- B. Plague
- C. Filaria (Correct Answer)
- D. Malaria
Explanation: ***Filaria*** - The **filarial worm** undergoes a **biological transmission cycle** in the mosquito vector where microfilariae develop through larval stages (L1 → L2 → L3) with multiplication. - This represents a **cyclopropagative cycle** (both development and multiplication occur in the vector). - In the context of this question and classical teaching, filaria is considered the standard example of biological transmission with vector multiplication. - The infective L3 larvae multiply from a single microfilaria, and multiple larvae can develop within one mosquito. *Plague* - **Plague** (*Yersinia pestis*) is transmitted by fleas through **mechanical transmission**. - Bacteria multiply in the flea's gut causing blockage (blocking transmission), but this is not considered a true biological cycle. - The pathogen does not undergo developmental stages in the vector. *Malaria* - **Malaria** (*Plasmodium* spp.) undergoes the **sporogonic cycle** in the mosquito, which is also a **cyclopropagative cycle**. - Gametocytes → ookinete → oocyst → sporozoites (development with multiplication). - While biologically similar to filaria, in classical epidemiology teaching, filaria is more commonly cited as the example for propagative transmission. *None of the options* - This option is incorrect as filaria demonstrates biological transmission with multiplication in the vector. - Both filaria and malaria technically undergo cyclopropagative cycles, but filaria is the conventional answer in medical education contexts.
Question 584: What is the most common cancer diagnosed in men?
- A. Bladder cancer
- B. Colorectal cancer
- C. Oral cancer (Correct Answer)
- D. Prostate cancer
Explanation: ***Oral cancer*** - **Oral cancer** is the most common cancer diagnosed in men in India, particularly cancers of the **lip, oral cavity, and oropharynx**. - India accounts for approximately **one-third of the global burden** of oral cancers. - Major risk factors include **tobacco chewing (gutka, pan masala, betel quid), smoking, and alcohol consumption**. - Early detection through **oral examination** and avoiding tobacco products are key preventive measures. *Prostate cancer* - While prostate cancer is the most common cancer in men in **Western populations**, it ranks **much lower in India** (typically 3rd-5th most common). - Incidence is increasing in urban Indian populations due to improved detection and lifestyle changes. *Bladder cancer* - **Bladder cancer** is significant but less common than oral cancer in Indian men. - Risk factors include **smoking** and occupational exposure to chemicals. *Colorectal cancer* - **Colorectal cancer** is increasing in incidence in India but remains less common than oral cancer in men. - Screening with **colonoscopy** is recommended for early detection, especially in those with family history.
Question 585: What is the caloric value of the nutritional supplement provided for a two-year-old child under the ICDS scheme?
- A. 500 Calories
- B. 300 Calories (Correct Answer)
- C. 200 Calories
- D. 400 Calories
Explanation: ***300 Calories*** - Under the **ICDS scheme guidelines in effect in 2012**, children aged 6 months to 6 years were provided a nutritional supplement of **300 kcal per day** along with 8-10g protein. - This supplement aimed to bridge the **nutritional gap** and prevent malnutrition in growing children. - **Note:** ICDS guidelines were subsequently revised (around 2017-2018), and current norms now specify **500 kcal** for the same age group. However, for this 2012 exam question, 300 kcal was the correct answer. *200 Calories* - This caloric value was **insufficient** even under the 2012 ICDS guidelines for meeting the daily supplemental nutritional requirements of a two-year-old child. - Providing only 200 calories would not adequately address the **energy demands** for growth and development in this age group. *400 Calories* - This specific caloric value was **not part of the standard ICDS supplementation schedule** in 2012. - The scheme specified clear categories: 300 kcal for normal children and 500 kcal for severely malnourished children, with no intermediate 400 kcal category. *500 Calories* - Under the **2012 ICDS guidelines**, this caloric value was reserved for **severely malnourished children** aged 6 months to 6 years (Grade III and IV malnutrition). - For a two-year-old with standard or moderate nutritional needs, the supplementation target was **300 kcal**, not 500 kcal. - **Current guidelines** (post-2017) now specify 500 kcal as the standard for all children 6 months to 6 years, but this was not the case in 2012.
Obstetrics and Gynecology
1 questionsWhich contraceptive method has the lowest pregnancy failure rate (typical use)?
NEET-PG 2012 - Obstetrics and Gynecology NEET-PG Practice Questions and MCQs
Question 581: Which contraceptive method has the lowest pregnancy failure rate (typical use)?
- A. Diaphragm
- B. Condom
- C. Intrauterine Contraceptive Device (IUCD) (Correct Answer)
- D. Oral Contraceptive Pills (OCP)
Explanation: ***Intrauterine Contraceptive Device (IUCD)*** - **IUCDs** are highly effective, with a **pregnancy failure rate of less than 1%** in typical use due to their long-acting and reversible nature, requiring no daily action from the user. - They are **fit-and-forget methods**, eliminating user error inherent in other forms of contraception, leading to very low typical use failure rates. *Diaphragm* - The **diaphragm** has a significantly higher typical use failure rate (around 12-16%) because its effectiveness depends on **correct placement** and consistent use with spermicide before each intercourse. - It is a **user-dependent method**, making its efficacy susceptible to improper use or non-use during sexual activity. *Condom* - **Condoms** have a typical use failure rate of about 13-18%, largely due to **incorrect use**, breakage, or slippage. - Their effectiveness relies heavily on **consistent and proper application** with every act of intercourse. *Oral Contraceptive Pills (OCP)* - **Oral Contraceptive Pills (OCPs)** have a typical use failure rate of approximately 7-9%, primarily because effectiveness is dependent on **daily adherence** at roughly the same time. - **Missed pills** are a common reason for failure, significantly increasing the risk of pregnancy compared to methods that do not require daily action.
Ophthalmology
3 questionsWhat is the most common cause of anterior uveitis?
What is the first clinical sign observed in a patient with anterior uveitis?
Among the following organisms, which is the most common cause of postoperative endophthalmitis following corneal transplantation?
NEET-PG 2012 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 581: What is the most common cause of anterior uveitis?
- A. CMV
- B. Toxoplasma
- C. Idiopathic (Correct Answer)
- D. Ankylosing spondylitis
Explanation: ***Idiopathic*** - In a significant proportion of cases of **anterior uveitis**, a specific cause cannot be identified, leading to a diagnosis of idiopathic uveitis. - This highlights the multifactorial nature of the condition, where various triggers or underlying predispositions may not always be evident. *CMV* - **Cytomegalovirus (CMV)** typically causes a **posterior uveitis** or **retinitis**, especially in immunocompromised individuals. - While CMV can rarely cause anterior uveitis, it is not the most common cause. *Toxoplasma* - **Toxoplasmosis** is a frequent cause of **posterior uveitis** or **chorioretinitis**, characterized by focal necrotic lesions in the retina. - It is not a common cause of isolated anterior uveitis, although anterior chamber inflammation can occur secondary to posterior disease. *Ankylosing spondylitis* - **Ankylosing spondylitis** is a well-known systemic condition associated with **acute anterior uveitis**. - However, while a significant association exists, it is not the single most common cause when considering all cases of anterior uveitis, many of which remain idiopathic.
Question 582: What is the first clinical sign observed in a patient with anterior uveitis?
- A. Presence of aqueous flare (Correct Answer)
- B. Presence of hypopyon
- C. Presence of miosis
- D. Presence of keratic precipitates
Explanation: ***Presence of aqueous flare*** - **Aqueous flare** is considered the **earliest clinical sign** of anterior uveitis, representing increased protein content in the anterior chamber due to breakdown of the **blood-aqueous barrier**. - It is detected as a visible "haze" when a **slit lamp beam** passes through the anterior chamber, similar to observing dust particles in a light beam. *Presence of hypopyon* - **Hypopyon** is a more severe sign, indicating a **layer of white blood cells** in the anterior chamber, representing a more advanced inflammatory process. - While it can occur in severe anterior uveitis, it is not typically the **first or earliest** clinical manifestation. *Presence of miosis* - **Miosis** (pupillary constriction) can be present in anterior uveitis due to **iris inflammation** and irritation of the sphincter muscle. - However, it is an indirect sign and typically occurs *after* the initial signs of inflammation in the aqueous humor, such as flare. *Presence of keratic precipitates* - **Keratic precipitates (KPs)** are deposits of inflammatory cells on the **endothelium of the cornea**. - These deposits are a result of sustained inflammation and typically appear *after* the initial inflammatory changes in the aqueous humor, such as flare, have already occurred.
Question 583: Among the following organisms, which is the most common cause of postoperative endophthalmitis following corneal transplantation?
- A. Streptococcus
- B. Pseudomonas
- C. Propionibacterium acnes
- D. Staph epidermidis (Correct Answer)
Explanation: ***Staph epidermidis*** - **Coagulase-negative Staphylococcus** (CoNS), including *S. epidermidis*, is the most frequent cause of **postoperative endophthalmitis** after both cataract surgery and corneal transplantation due to its presence on the normal ocular flora. - These organisms can form **biofilms on intraocular lenses** or transplanted corneal tissue, making eradication difficult. *Streptococcus* - While *Streptococcus* species can cause endophthalmitis, they are associated with a **more virulent and rapid onset** of severe inflammation and are not the most common causative agents of postoperative endophthalmitis compared to *S. epidermidis*. - They tend to cause more aggressive infections with often **poorer visual outcomes**. *Propionibacterium acnes* - *Propionibacterium acnes* can cause a **late-onset, indolent form of endophthalmitis**, typically months or even years after surgery. - While it is a recognized cause, it is far **less common** than *Staphylococcus epidermidis* in immediate or early postoperative cases. *Pseudomonas* - **Pseudomonas aeruginosa** is an aggressive and rapid-onset pathogen often associated with **severe keratitis** or **post-traumatic endophthalmitis**. - Although it can cause postoperative endophthalmitis, it is **much less common** than coagulase-negative staphylococci due to its infrequency on normal conjunctival flora.
Physiology
1 questionsWhat is the characteristic of the second Purkinje image in relation to eye movement?
NEET-PG 2012 - Physiology NEET-PG Practice Questions and MCQs
Question 581: What is the characteristic of the second Purkinje image in relation to eye movement?
- A. Inverted and moves in same direction
- B. Inverted and moves in opposite direction
- C. Erect and moves in same direction (Correct Answer)
- D. Erect and moves in opposite direction
Explanation: ***Erect and moves in same direction*** - The second Purkinje image (P2) is formed by reflection from the **posterior surface of the cornea**. - This surface acts as a convex mirror, producing a **virtual, erect, and diminished image**. - The image moves in the **same direction** as the eye movement, characteristic of reflections from the first three Purkinje images (P1, P2, P3). - P2 is clinically used in keratometry and assessment of corneal curvature. *Erect and moves in opposite direction* - While the image orientation (erect) would apply to P2, the direction of movement is incorrect. - Only the **fourth Purkinje image (P4)**, formed by the **posterior lens surface**, moves in the opposite direction to eye movement. - P4 is the only inverted Purkinje image due to reflection from the concave posterior lens surface. *Inverted and moves in same direction* - The second Purkinje image is **erect, not inverted**. - All Purkinje images are erect except P4, which is inverted due to reflection from the concave posterior lens surface. - This combination (inverted + same direction) does not correspond to any Purkinje image. *Inverted and moves in opposite direction* - This describes the **fourth Purkinje image (P4)**, not the second. - P4 is formed by reflection from the **posterior surface of the lens** (concave surface), which produces an inverted image. - The second Purkinje image (P2) is always erect, being formed by the posterior corneal surface.