Biochemistry
1 questionsEffect of environment on genes is called?
NEET-PG 2012 - Biochemistry NEET-PG Practice Questions and MCQs
Question 581: Effect of environment on genes is called?
- A. Euthenics
- B. Positive Eugenics
- C. Negative Eugenics
- D. Epigenetics (Correct Answer)
Explanation: ***Epigenetics*** - **Epigenetics** refers to heritable changes in **gene expression** that do not involve alterations to the underlying **DNA sequence**. - These changes are often influenced by **environmental factors**, such as diet, stress, and exposure to toxins, which can affect how genes are turned on or off. *Positive Eugenics* - **Positive eugenics** aims to improve the human population by encouraging the reproduction of individuals deemed to have "desirable" traits. - This concept is ethically controversial and focuses on directed breeding rather than environmental gene influence. *Negative Eugenics* - **Negative eugenics** aims to reduce the prevalence of "undesirable" traits in the human population by discouraging or preventing the reproduction of individuals deemed to possess them. - Like positive eugenics, this is a highly controversial concept focused on limiting reproduction based on perceived genetic quality. *Euthenics* - **Euthenics** is a movement focused on improving human well-being and development by improving living conditions and the environment. - While it acknowledges the impact of the environment, it focuses on societal and lifestyle improvements rather than the direct molecular changes in gene expression.
Community Medicine
3 questionsThe study of human diseases and their impact on society is known as?
Which occupational exposure may cause sterility in females ?
In pediatric growth assessment, what is the typical relationship observed between height and weight in healthy children?
NEET-PG 2012 - Community Medicine NEET-PG Practice Questions and MCQs
Question 581: The study of human diseases and their impact on society is known as?
- A. Public health
- B. Epidemiology (Correct Answer)
- C. Health sociology
- D. Medical anthropology
Explanation: ***Epidemiology*** - **Epidemiology** is defined as the study of the distribution, determinants, patterns, and frequency of health and disease conditions in defined populations, including their **impact on society**. - It is the fundamental science of **public health** that specifically studies how diseases affect populations and society through systematic investigation using statistical and analytical methods. - Epidemiological studies directly examine disease burden, mortality, morbidity, and societal impact, making it the most precise answer for studying diseases and their societal consequences. - Key epidemiological measures (incidence, prevalence, DALYs) quantify the **societal impact** of diseases. *Public health* - **Public health** is the broader applied field that uses epidemiological findings to implement programs, policies, and interventions. - While public health addresses disease impact, it is primarily an **action-oriented discipline** focused on prevention and health promotion, not just the study of diseases. - Public health encompasses multiple disciplines including epidemiology, health education, environmental health, and health policy. *Health sociology* - **Health sociology** (or medical sociology) examines social factors, behaviors, and structures that influence health outcomes and healthcare access. - It focuses on social determinants, health inequalities, and illness behavior from a **sociological perspective**, rather than the scientific study of disease distribution and patterns. *Medical anthropology* - **Medical anthropology** studies health, illness, and healing through a **cultural and ethnographic lens**. - It examines how different cultures understand disease, healing practices, and medical systems, rather than studying disease patterns and their population-level impact.
Question 582: Which occupational exposure may cause sterility in females ?
- A. Lead
- B. Carbon monoxide
- C. Mercury
- D. Agricultural insecticides (Correct Answer)
Explanation: ***Agricultural insecticides*** - Exposure to **organochlorine** and **organophosphate** insecticides can have significant **reproductive toxicity** in females, leading to **infertility** or **sterility**. - These chemicals can disrupt **hormonal balance**, interfere with **ovarian function**, cause **menstrual irregularities**, and lead to **developmental toxicity** in offspring. - Well-documented occupational hazard in agricultural workers with chronic exposure. *Lead* - Lead is a well-established **reproductive toxicant** affecting **both males and females**. - In females, lead causes **menstrual irregularities**, **ovarian dysfunction**, **reduced fertility**, **spontaneous abortions**, and can contribute to sterility. - It disrupts the **hypothalamic-pituitary-ovarian axis** and has direct **gonadotoxic effects**. - While agricultural insecticides are more specifically associated with female sterility in occupational contexts, lead is also a significant reproductive hazard. *Carbon monoxide* - Carbon monoxide poisoning primarily causes **hypoxia** by binding to hemoglobin, forming **carboxyhemoglobin**. - It does not directly cause **sterility** in females; its main reproductive concern relates to **fetal hypoxia** and adverse pregnancy outcomes during exposure. *Mercury* - Mercury exposure, particularly **methylmercury**, is a known **neurotoxin** and can cause **developmental abnormalities**. - While it can affect pregnancy outcomes and cause **menstrual disorders** at high exposures, it is not typically cited as a primary occupational cause of **female sterility** compared to agricultural insecticides.
Question 583: In pediatric growth assessment, what is the typical relationship observed between height and weight in healthy children?
- A. Negative Correlation
- B. No Correlation
- C. Inverse Relationship
- D. Positive Correlation (Correct Answer)
Explanation: ***Positive Correlation*** - In healthy children, as **height increases**, **weight generally also increases** in a predictable pattern, demonstrating a **positive correlation** between these two variables. - This is a fundamental aspect of normal pediatric growth, where both height and weight increase together as children develop. - The **correlation coefficient** between height and weight in healthy children is typically **strong and positive** (r > 0.7). *Negative Correlation* - A **negative correlation** would imply that as height increases, weight decreases, which contradicts normal growth patterns in healthy children. - This relationship might be observed in certain pathological conditions (e.g., severe malnutrition with stunting) but is not characteristic of normal development. *No Correlation* - Stating **no correlation** would mean that changes in height have no predictable linear relationship with changes in weight, which contradicts well-established growth data. - Height and weight are both key anthropometric indicators that are inherently linked during normal growth. *Inverse Relationship* - An **inverse relationship** is synonymous with a negative correlation, suggesting that as one variable increases, the other decreases. - This is incorrect for normal pediatric growth, where height and weight generally trend upwards together throughout childhood.
Microbiology
1 questionsThe idiotype of an antibody is determined by -
NEET-PG 2012 - Microbiology NEET-PG Practice Questions and MCQs
Question 581: The idiotype of an antibody is determined by -
- A. Fc region
- B. Hinge region
- C. Carboxy end
- D. Amino end (Correct Answer)
Explanation: ***Amino end*** - The **idiotypic class** of an antibody is determined by the unique amino acid sequences within the **variable regions** of both the heavy and light chains, located at the **amino-terminal end** of the antibody. - These variable regions form the **antigen-binding sites**, giving each antibody its specific binding capabilities and thus its idiotype. *Fc region* - The **Fc (fragment crystallizable) region** is the tail region of an antibody that interacts with cell surface receptors and other immune system molecules. - It determines the **isotype (class)** of the antibody (e.g., IgG, IgM) and mediates effector functions but does not define the idiotype. *Hinge region* - The **hinge region** is a flexible segment in the middle of the heavy chains of IgG, IgA, and IgD antibodies. - It allows flexibility between the antigen-binding (Fab) arms, facilitating bivalent binding, but does not determine the idiotype. *Carboxy end* - The **carboxy end** (C-terminus) of the heavy and light chains typically corresponds to the constant regions of the antibody. - While it contributes to the antibody's overall structure and effector functions (especially the Fc region), it does not contain the unique sequences that define the **idiotype**.
Ophthalmology
4 questionsWhich type of congenital cataract is commonly associated with significant visual defects?
Which type of cataract is specifically associated with decreased reading ability?
What is the primary mechanism of pathogenesis in acute angle closure glaucoma?
What condition is characterized by cherry red spot at the macula with retinal whitening?
NEET-PG 2012 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 581: Which type of congenital cataract is commonly associated with significant visual defects?
- A. Punctate Cataract
- B. Blue dot cataract
- C. Fusiform cataract
- D. Nuclear cataract (Correct Answer)
Explanation: ***Nuclear cataract*** - It involves the **nucleus** of the lens, which is the central and most visually critical part. - This type of cataract can cause **significant visual impairment** due to its central location and density, impacting early visual development. *Punctate Cataract* - These are **small, dot-like opacities** that are usually clinically insignificant and do not typically cause significant visual defects. - They are often **peripheral** or very fine, thus not obstructing the central visual axis. *Blue dot cataract* - Also known as **cerulean cataract**, this type consists of small, bluish opacities in the lens cortex. - While congenital, it often has **minimal impact on vision** and is frequently observed incidentally. *Fusiform cataract* - This cataract forms in the shape of a **spindle or needle**, usually along the visual axis. - While it can sometimes cause minor visual compromise, its impact is generally **less severe** compared to a dense nuclear cataract.
Question 582: Which type of cataract is specifically associated with decreased reading ability?
- A. Blue dot cataract
- B. Nuclear cataract (Correct Answer)
- C. Fusiform cataract
- D. Punctate cataract
Explanation: ***Nuclear cataract*** - **Nuclear cataracts** cause progressive hardening and yellowing of the lens nucleus with increased refractive index - This produces a **myopic shift** that initially causes **"second sight"** (temporary improvement in near vision) - However, as the cataract progresses, the increasing opacity leads to **overall visual decline affecting both distance and near vision**, including reading ability - Among the given options, nuclear cataract is the most common age-related cataract that significantly impairs vision including reading *Blue dot cataract* - **Blue dot cataracts** (cerulean cataracts) are small, bluish peripheral opacities, usually congenital and stationary - They rarely cause significant visual impairment and do not affect reading ability *Fusiform cataract* - **Fusiform cataracts** are congenital spindle-shaped opacities along the visual axis - While they can affect vision if dense, they are rare and not typically associated with progressive reading difficulty *Punctate cataract* - **Punctate cataracts** are small, scattered dot-like opacities in the lens - They are often congenital or age-related and cause minimal visual disturbance - Not specifically associated with decreased reading ability
Question 583: What is the primary mechanism of pathogenesis in acute angle closure glaucoma?
- A. Increased secretion of aqueous humor
- B. Outflow obstruction due to anatomical factors (Correct Answer)
- C. Increased absorption of aqueous humor
- D. Decreased ciliary body function
Explanation: ***Outflow obstruction due to anatomical factors*** - **Acute angle-closure glaucoma (AACG)** occurs due to a sudden blockage of the **trabecular meshwork**, which is the primary drainage pathway for aqueous humor. - This blockage is caused by anatomical predispositions, such as a **narrow anterior chamber angle**, relatively large lens, and **pupillary block** leading to iris bombé with peripheral iris bowing forward. - The iridocorneal angle closure prevents aqueous humor drainage, causing **rapid IOP elevation**. *Increased secretion of aqueous humor* - While increased aqueous humor production can contribute to elevated intraocular pressure, it is **not the primary mechanism** in acute angle-closure glaucoma. - This mechanism is more relevant in **open-angle glaucoma** or conditions with ciliary body overactivity. - AACG's hallmark is **outflow obstruction**, not increased production. *Decreased ciliary body function* - Decreased ciliary body function would **reduce aqueous humor production**, leading to **hypotony** (low IOP), not elevated pressure. - This is the opposite of what occurs in AACG, where IOP rises dramatically due to impaired drainage. - Ciliary body dysfunction is seen in conditions like **uveitis** or post-surgical complications. *Increased absorption of aqueous humor* - **Increased absorption** of aqueous humor would **reduce intraocular pressure**, which is the opposite of what occurs in acute angle-closure glaucoma. - The disease is characterized by a **rapid and severe rise in intraocular pressure** due to impaired outflow, not enhanced absorption. - Normal aqueous absorption occurs via trabecular and uveoscleral pathways, both of which are blocked in AACG.
Question 584: What condition is characterized by cherry red spot at the macula with retinal whitening?
- A. CRVO
- B. CRAO (Correct Answer)
- C. Diabetic retinopathy
- D. Syphilitic retinopathy
Explanation: ***CRAO*** - **Central retinal artery occlusion (CRAO)** is characterized by **sudden, profound, painless monocular vision loss**. - The classic funduscopic finding is a **cherry-red spot at the macula** with diffuse **retinal whitening** due to ischemia. *CRVO* - **Central retinal vein occlusion (CRVO)** presents with **painless vision loss** but typically shows **hemorrhages**, **dilated tortuous veins**, and **cotton wool spots** on funduscopic exam. - It does not usually cause retinal whitening or a cherry-red spot. *Diabetic retinopathy* - **Diabetic retinopathy** is characterized by **microaneurysms**, **hemorrhages**, **hard exudates**, and **cotton wool spots**, and can lead to neovascularization. - It does not present with acute retinal whitening or a cherry-red spot in the macula. *Syphilitic retinopathy* - **Syphilitic retinopathy** can cause a variety of presentations, including **retinal vasculitis**, **chorioretinitis**, and **optic neuritis**. - It does not typically manifest as a cherry-red spot with diffuse retinal whitening at the macula.
Psychiatry
1 questionsIn the context of understanding patient behavior and therapeutic relationships, what is the definition of social psychology?
NEET-PG 2012 - Psychiatry NEET-PG Practice Questions and MCQs
Question 581: In the context of understanding patient behavior and therapeutic relationships, what is the definition of social psychology?
- A. The study of human relationships and behavior in social contexts
- B. The examination of cultural influences on behavior
- C. A field that does not exist
- D. The study of how individuals think, feel, and behave in social situations (Correct Answer)
Explanation: ***The study of how individuals think, feel, and behave in social situations*** - **Social psychology** focuses on understanding how individual thoughts, feelings, and behaviors are influenced by the actual, imagined, or implied presence of others. - This field examines topics like **social perception**, **attitude formation**, and **interpersonal relationships**, which are crucial for understanding therapeutic interactions. *The study of human relationships and behavior in social contexts* - While this option is close, it is a broader and less precise definition. Social psychology specifically focuses on the **individual's psychological processes** within social contexts. - This definition could also encompass fields like **sociology**, which studies groups and societies rather than the individual experience. *The examination of cultural influences on behavior* - This describes **cultural psychology** or **cross-cultural psychology**, which explicitly investigates the impact of culture on psychological processes. - While culture is a social context, social psychology's scope is broader, encompassing all forms of social influence, not just cultural ones. *A field that does not exist* - This statement is incorrect; **social psychology is a well-established and active field** within psychology. - It has a rich history and continues to contribute significantly to our understanding of human behavior and interactions.