p1 pyq from 86 - genetic Flashcards
1. Pedigree analysis in genetic counselling (2022)
Pedigree analysis in genetic counseling involves mapping a family’s genetic history to identify patterns of inheritance for specific traits or disorders. It helps in understanding the genetic risks, advising on potential health concerns, and making informed decisions regarding reproduction. By analyzing the pedigrees, counselors can identify carriers, predict the likelihood of genetic conditions in future generations, and provide guidance on preventive measures and management strategies. Pedigree charts are crucial for diagnosing inherited conditions and offering tailored genetic advice.
2. Briefly describe the various methods used in the genetic study of man (20 M, 2017)
Methods in genetic studies include pedigree analysis for tracing inheritance patterns, twin studies to differentiate genetic from environmental influences, population genetics to study allele frequencies and evolutionary forces, cytogenetics for chromosomal abnormalities, molecular genetics for DNA sequencing and gene identification, genome-wide association studies (GWAS) to identify genetic variations linked to traits, and epigenetics to explore gene expression regulation. These methods provide comprehensive insights into genetic mechanisms, inheritance, and the role of genetics in health and disease.
3. Twin method in human genetics (10Marks 2013)
The twin method involves studying monozygotic (identical) and dizygotic (fraternal) twins to understand the genetic and environmental influences on traits. Monozygotic twins share all their genes, while dizygotic twins share about 50%. By comparing trait concordance rates between the two types of twins, researchers can estimate heritability. The twin method helps disentangle nature versus nurture debates, providing insights into genetic predispositions and environmental impacts on traits such as intelligence, behavior, and diseases.
4. What do you understand by Immunogenetics? Explain with suitable examples (15Marks 2015)
Immunogenetics studies the genetic basis of immune system function. It explores how genetic variations influence immune responses and susceptibility to diseases. For example, the HLA (Human Leukocyte Antigen) genes play a crucial role in immune recognition and organ transplantation compatibility. Genetic mutations in BRCA1/BRCA2 can affect the immune system’s ability to repair DNA, increasing cancer risk. Immunogenetics helps understand autoimmune diseases, vaccine responses, and the development of personalized medicine.
5. Anthropological relevance of population genetics (20 Marks — 2009)
Population genetics is vital in anthropology for studying genetic variation within and between human populations, shedding light on human evolution, migration patterns, and adaptation. It helps trace ancestry, understand genetic diversity, and identify evolutionary forces like natural selection, genetic drift, and gene flow. Techniques like haplogroup analysis and allele frequency studies reveal insights into population history and structure. Population genetics bridges the gap between genetics and anthropology, providing a genetic perspective on human cultural and biological evolution.
6. Thrifty genotype (20 Marks — 2009)
The “thrifty genotype” hypothesis suggests that certain genetic traits, advantageous in ancient times for efficient energy storage and utilization during food scarcity, predispose modern individuals to metabolic diseases like obesity and diabetes in environments with abundant food. Genes promoting fat storage and insulin resistance were beneficial for survival in hunter-gatherer societies but have become detrimental in sedentary lifestyles with high-calorie diets. Understanding the thrifty genotype aids in addressing metabolic health issues and developing preventive strategies.
7. Pedigree Analysis (2007)
Pedigree analysis involves creating a family tree that traces the inheritance of specific traits or genetic disorders. It helps identify carriers, affected individuals, and inheritance patterns (e.g., autosomal dominant, autosomal recessive, X-linked). This method is crucial in genetic counseling to predict genetic risks, provide diagnostic insights, and guide decisions on genetic testing and family planning. Pedigree charts offer a visual representation of genetic relationships and help assess the likelihood of passing genetic conditions to offspring.
8. Genome Study (2007)
Genome studies involve analyzing the complete set of an organism’s DNA, including all of its genes. Techniques like whole-genome sequencing and genome-wide association studies (GWAS) identify genetic variations linked to diseases, traits, and evolutionary history. Genome studies provide insights into gene function, genetic diversity, and the molecular basis of traits and diseases. They contribute to personalized medicine, evolutionary biology, and understanding the genetic architecture of complex traits, offering a comprehensive view of genetic information.
9. Discuss the areas in which the knowledge of human genetics can be applied (2004)
Human genetics knowledge applies to various fields: medicine (diagnosing genetic disorders, developing gene therapies), forensics (DNA profiling for identification), anthropology (studying human evolution and population genetics), agriculture (improving crop and livestock breeds), public health (understanding genetic predispositions to diseases), pharmacogenomics (personalizing drug treatments based on genetic profiles), and genetic counseling (advising on genetic risks and family planning). Genetics also informs ethical, legal, and social issues related to genetic information use.
10. Discuss the role of twins in nature – nurture problems and illustrate your answer with suitable examples (1999)
Twins play a crucial role in studying the nature versus nurture debate by allowing comparisons between monozygotic (identical) and dizygotic (fraternal) twins. For example, studies on twins raised apart can reveal the extent of genetic influence on traits like intelligence, personality, and susceptibility to diseases. Higher concordance rates in monozygotic twins suggest genetic factors, while differences highlight environmental influences. Twin studies help disentangle the complex interactions between genetics and environment in shaping human behavior and development.
11. Define twins. Describe the methods of diagnosis of twins. In what way are twins useful in the study of human genetics? (1998)
Twins are individuals born from the same pregnancy. Monozygotic twins arise from a single fertilized egg splitting into two embryos, sharing identical genetic material. Dizygotic twins result from two separate eggs fertilized by different sperm, sharing about 50% of their genes. Methods for diagnosing twins include ultrasound imaging and chorionicity assessment. Twins are useful in genetic studies by providing natural experiments to separate genetic and environmental influences, allowing researchers to estimate heritability and understand genetic contributions to traits and diseases.
1. What assumptions must be met for a population to be in genetic equilibrium? Explain the importance of genetic equilibrium. (15M, 2023)
For a population to be in genetic equilibrium, the Hardy-Weinberg assumptions must be met: 1) large population size (no genetic drift), 2) no mutation, 3) no migration (no gene flow), 4) random mating, and 5) no natural selection. Genetic equilibrium is important as it provides a baseline to detect evolutionary forces at work, such as selection, drift, or gene flow. It serves as a null model to measure deviations, which indicate the presence of evolutionary processes shaping genetic variation in populations.
2. Balanced and transient genetic polymorphism. (10M, 2022)
Balanced genetic polymorphism refers to the stable coexistence of multiple alleles at a locus due to selective advantages, such as in heterozygote advantage (e.g., sickle cell trait). Transient genetic polymorphism is temporary, where allele frequencies change over time and one allele eventually becomes fixed or lost. An example is the transient presence of a beneficial mutation spreading through a population until it becomes fixed. Balanced polymorphisms maintain genetic diversity, whereas transient polymorphisms reflect ongoing evolutionary changes.
3. Discuss the role of evolutionary forces in creating human diversity. (20M, 2022)
Evolutionary forces shaping human diversity include: 1) Mutation, introducing new genetic variations. 2) Natural selection, favoring advantageous traits, leading to adaptation. 3) Genetic drift, causing random changes in allele frequencies, especially in small populations. 4) Gene flow, mixing genetic material between populations through migration. 5) Non-random mating, influencing allele distribution. These forces interact, producing the genetic variation and adaptability seen in human populations, contributing to diverse phenotypes and genetic traits.
4. Genetic drift. (10M, 2020)
Genetic drift is the random fluctuation of allele frequencies in a population, more pronounced in small populations. It leads to the loss or fixation of alleles, reducing genetic variation and potentially impacting population fitness. Drift can result from events like bottlenecks (drastic population size reduction) or founder effects (new population established by a small number of individuals). Unlike natural selection, genetic drift is random and does not necessarily favor advantageous traits.
5. How do marriage rules impact the gene pool of populations? (15M, 2020)
Marriage rules, such as endogamy (marrying within a group) and exogamy (marrying outside the group), significantly affect gene pools. Endogamy increases genetic homogeneity and the likelihood of inherited disorders due to increased homozygosity. Exogamy promotes genetic diversity by introducing new alleles. Rules like consanguinity (marriage between relatives) can lead to higher frequencies of recessive genetic disorders. Social practices influence allele distribution, shaping population genetic structure and health.
6. Differentiate between transient and balanced genetic polymorphisms. Illustrate your answer with suitable examples from human populations. (15M, 2019)
Transient polymorphism involves temporary allele frequency changes until one allele becomes fixed or lost (e.g., a new advantageous mutation spreading). Balanced polymorphism maintains multiple alleles at stable frequencies due to selective advantages (e.g., sickle cell trait, where heterozygotes have malaria resistance). Transient polymorphisms reflect ongoing evolutionary changes, while balanced polymorphisms sustain genetic diversity within populations.
7. Implications of mutation in evolution. (10M, 2019)
Mutations introduce new genetic variations, serving as the raw material for evolution. Beneficial mutations can be favored by natural selection, leading to adaptation. Harmful mutations may be eliminated, while neutral mutations can accumulate as genetic drift. Mutations drive evolutionary change by providing diversity for selection to act upon, influencing species’ ability to adapt to changing environments and potentially leading to the emergence of new species.
8. Hardy-Weinberg Law. (10M, 2017)
The Hardy-Weinberg Law states that allele and genotype frequencies in a large, randomly mating population remain constant from generation to generation in the absence of evolutionary forces (mutation, selection, gene flow, genetic drift). It is expressed as (p^2 + 2pq + q^2 = 1), where (p) and (q) are allele frequencies. This principle serves as a null model to study genetic variations and deviations, indicating evolutionary influences.
9. Define Genetic polymorphism. Give details of its types with suitable examples. (15M, 2015)
Genetic polymorphism refers to the existence of two or more alleles at a locus in a population. Types include balanced polymorphism (e.g., sickle cell trait with malaria resistance) and transient polymorphism (e.g., new beneficial mutations spreading). Polymorphisms contribute to genetic diversity and adaptation, influencing traits like blood type (ABO system) and disease susceptibility.
10. Discuss the factors affecting gene frequencies among human populations. (20M, 2014)
Factors include: 1) Mutation - introduces new alleles. 2) Natural selection - favors advantageous alleles. 3) Genetic drift - causes random allele frequency changes, especially in small populations. 4) Gene flow - introduces alleles from other populations. 5) Non-random mating - affects allele distribution. 6) Population size - larger populations buffer against drift. 7) Cultural practices - influence mating patterns and gene flow. These factors interact, shaping genetic diversity and evolution in human populations.
11. What do you understand by ‘Genetic Load’ in a population? How is it measured and what are the important factors that can influence it? (15M, 2013)
Genetic load is the presence of deleterious alleles in a population, reducing average fitness. It is measured by comparing the fitness of a population with an ideal, mutation-free population. Factors influencing genetic load include mutation rate, selection pressure, genetic drift, and gene flow. High genetic load can lead to increased susceptibility to diseases and reduced overall health, impacting population survival and adaptation.
12. What are the genetic effects of Consanguinity? Give examples? (20M, 2012)
Consanguinity (marriage between relatives) increases homozygosity, leading to higher chances of recessive genetic disorders. Examples include higher rates of cystic fibrosis, Tay-Sachs disease, and sickle cell anemia in populations with prevalent consanguineous marriages. It also increases the likelihood of inherited metabolic disorders and congenital anomalies. While consanguinity can perpetuate genetic diseases, it can also maintain beneficial traits in small, isolated populations.
13. Genetic Polymorphism (15M, 2011)
Genetic polymorphism is the occurrence of multiple alleles at a locus within a population. It includes balanced polymorphism, where alleles are maintained by selective advantages (e.g., sickle cell trait), and transient polymorphism, where allele frequencies change over time (e.g., new beneficial mutations). Polymorphisms contribute to genetic diversity, influencing traits like blood type and disease resistance, and play a crucial role in adaptation and evolution.
14. Conditions necessary for the operation of Hardy-Weinberg Law. (15M, 2011)
Conditions for Hardy-Weinberg equilibrium include: 1) large population size (no genetic drift), 2) no mutation, 3) no migration (no gene flow), 4) random mating, and 5) no natural selection. These conditions ensure allele and genotype frequencies remain constant across generations, providing a baseline to detect evolutionary influences. Deviations from equilibrium indicate the action of evolutionary forces such as selection, mutation, or gene flow.
15. What is Balanced Genetic Polymorphism? How is it maintained in a population? (30M, 2010)
Balanced genetic polymorphism refers to the stable coexistence of multiple alleles at a locus, maintained by selective advantages. Examples include heterozygote advantage (e.g., sickle cell trait) and frequency-dependent selection (e.g., host-parasite interactions). These mechanisms ensure that no single allele becomes fixed, preserving genetic diversity. Balanced polymorphisms are crucial for population adaptability and resilience, providing a genetic reservoir for evolving environmental conditions.
16. What is genetic load’ and what factors influence it? (30 Marks — 2009)
Genetic load is the reduction in population fitness due to the presence of deleterious alleles. It is influenced by mutation rates, selection pressures, inbreeding, genetic drift, and gene flow. High mutation rates introduce more deleterious alleles. Selection pressure can eliminate harmful alleles, while inbreeding increases homozygosity, revealing deleterious recessive alleles. Genetic drift randomly changes allele frequencies, potentially increasing genetic load in small populations. Gene flow can introduce new alleles, altering genetic load.
17. Inbreeding (S.N - 2008)
Inbreeding is the mating of individuals closely related genetically, increasing homozygosity and the likelihood of recessive genetic disorders. It can lead to inbreeding depression, characterized by reduced fitness and increased prevalence of genetic diseases. Inbreeding is common in isolated populations and can have significant evolutionary and health implications.
18. What do you understand by Hardy-Weinberg equilibrium? Discuss the factors that produce and redistribute variations. (L.Q - 2008)
Hardy-Weinberg equilibrium describes a population where allele and genotype frequencies remain constant across generations, assuming no evolutionary forces. Factors producing and redistributing variations include mutations (introducing new alleles), natural selection (favoring advantageous traits), genetic drift (random changes in small populations), gene flow (exchange of alleles between populations), and non-random mating (affecting allele distribution). These factors disrupt equilibrium, leading to genetic diversity and evolution.
19. Problems of Inbreeding (S. N - 2005)
Inbreeding problems include increased homozygosity, revealing recessive genetic disorders, leading to inbreeding depression (reduced fitness). It can result in higher incidences of congenital anomalies, genetic diseases, and decreased fertility. Inbreeding reduces genetic diversity, limiting adaptive potential and increasing vulnerability to environmental changes. Management of inbreeding is crucial for maintaining population health and genetic diversity.
20. Genetic polymorphism and selection (S.N - 2003)
Genetic polymorphism refers to the presence of multiple alleles at a locus within a population, contributing to genetic diversity. Selection acts on these polymorphisms, maintaining advantageous alleles (balanced polymorphism) or favoring certain alleles over others (directional selection). Examples include sickle cell trait and its relation to malaria resistance. Selection shapes genetic variation, influencing population adaptability and evolution.
21. Describe the major causes of change in gene frequency of a population (L.Q - 2003)
Major causes include: 1) Mutation - introduces new alleles. 2) Natural selection - favors advantageous alleles. 3) Genetic drift - random changes, especially in small populations. 4) Gene flow - exchange of alleles between populations. 5) Non-random mating - affects allele distribution. These factors interact, shaping genetic diversity and evolution, altering gene frequencies and population structure.
22. What are the statistical methods used in Physical Anthropology? (L.Q - 2001)
Statistical methods include: 1) Descriptive statistics (mean, median, mode, standard deviation) to summarize data. 2) Inferential statistics (t-tests, chi-square tests) to draw conclusions about populations from samples. 3) Regression analysis to examine relationships between variables. 4) Factor analysis to identify underlying factors. 5) Cluster analysis for grouping similar individuals. These methods help analyze anthropometric data, genetic variation, and evolutionary patterns.
23. Mutation (S.N - 1998)
Mutation is a change in the DNA sequence, creating genetic diversity. It can be beneficial, neutral, or deleterious. Mutations occur spontaneously or due to environmental factors (radiation, chemicals). They provide raw material for evolution, introducing new alleles for natural selection to act upon. Mutations impact genetic variability and adaptability of populations, influencing evolutionary processes.
24. Discuss the concept of Mendelian Population’ and its application in the study of anthropogenetic variations in India. (L.Q - 1997)
A Mendelian population is a group of interbreeding individuals sharing a common gene pool. It follows Mendelian inheritance principles. In India, studying Mendelian populations helps understand genetic diversity, disease prevalence, and evolutionary history. Applications include examining caste-based genetic variations, understanding the impact of endogamy, and tracing ancestry. It aids in public health strategies and understanding human genetic diversity in complex social structures.
25. Discuss the concepts of balanced polymorphism & relaxed selection with special reference to malaria-dependent polymorphism in Man. (S.N -1994)
Balanced polymorphism maintains multiple alleles at stable frequencies due to selective advantages, such as heterozygote advantage (e.g., sickle cell trait confers malaria resistance). Relaxed selection occurs when selective pressures are reduced, allowing deleterious alleles to persist. Malaria-dependent polymorphism, like sickle cell trait, exemplifies balanced polymorphism where heterozygotes have survival advantages in malaria-endemic regions. These concepts illustrate how genetic diversity is maintained under specific environmental pressures.
26. Inbreeding and cross breeding (S.N -1993)
Inbreeding involves mating between genetically related individuals, increasing homozygosity and the risk of recessive genetic disorders. Crossbreeding involves mating between genetically unrelated individuals, increasing heterozygosity and genetic diversity. Crossbreeding can improve fitness and reduce genetic diseases. In contrast, inbreeding can lead to inbreeding depression and reduced population health. Both practices have significant implications for genetic management and population sustainability.
27. Is inbreeding different from consanguinity? Give an account of inbreeding studies in India and comment on their social relevance. (L.Q - 1987)
Inbreeding refers to mating between genetically related individuals, while consanguinity specifically denotes mating between close relatives (e.g., cousins). Inbreeding studies in India show increased prevalence of genetic disorders in communities practicing consanguineous marriages. Social relevance includes understanding health implications, managing genetic diseases, and informing public health policies. Addressing consanguinity-related issues can improve population health and genetic diversity.
28. Discuss role of genetic drift, mutation and migration as the causes of variation. (L.Q -1985)
Genetic drift causes random allele frequency changes, more pronounced in small populations, leading to reduced genetic diversity. Mutation introduces new alleles, providing raw material for evolution and increasing genetic variation. Migration (gene flow) introduces alleles from other populations, increasing genetic diversity and reducing differences between populations. These forces interact, shaping genetic variation, population structure, and evolutionary trajectories.
1. Describe the causes of structural abnormalities of chromosomes with suitable examples. 15M—2023
Structural abnormalities of chromosomes occur due to deletions (e.g., Cri-du-chat syndrome caused by a deletion on chromosome 5), duplications (e.g., Charcot-Marie-Tooth disease type 1A due to a duplication on chromosome 17), inversions (e.g., inversion of chromosome 9), and translocations (e.g., chronic myelogenous leukemia caused by a translocation between chromosomes 9 and 22). These abnormalities can result from errors during DNA replication, repair, or meiosis.
2. Genetic imprinting in human diseases. 10M—2022
Genetic imprinting involves the differential expression of genes depending on their parent of origin. Diseases like Prader-Willi syndrome and Angelman syndrome result from imprinting defects on chromosome 15. In Prader-Willi syndrome, the paternal allele is lost or mutated, while in Angelman syndrome, the maternal allele is affected. Imprinting disorders highlight the importance of epigenetic regulation in human health.
3. “Chromosomal aberrations can play havoc with the human body and mind.” Explain with suitable examples. (15 Marks, 2021)
Chromosomal aberrations such as Down syndrome (trisomy 21) cause intellectual disability, developmental delays, and physical abnormalities. Turner syndrome (45,X) leads to short stature, infertility, and cardiovascular issues. Klinefelter syndrome (47,XXY) results in hypogonadism, infertility, and learning difficulties. These examples illustrate how chromosomal anomalies disrupt normal development and function, impacting both the body and mind.
4. How many numerical aberrations in sex chromosomes lead to genetic disorders? 15 M (2020)
Numerical aberrations in sex chromosomes include Turner syndrome (45,X), Klinefelter syndrome (47,XXY), Triple X syndrome (47,XXX), and XYY syndrome (47,XYY). Turner syndrome causes short stature and infertility, Klinefelter syndrome leads to hypogonadism and learning difficulties, Triple X syndrome generally results in mild symptoms, and XYY syndrome can cause tall stature and learning disabilities. These disorders result from errors in meiotic division.
5. Describe the mechanism for structural anomalies of autosomes with diagrams. 20 marks (2018)
Structural anomalies of autosomes include deletions (loss of a chromosome segment), duplications (extra copy of a chromosome segment), inversions (reversal of a chromosome segment), and translocations (exchange of segments between chromosomes). Diagrams illustrating these mechanisms can show the normal and abnormal chromosome structures, highlighting the regions affected and potential genetic outcomes.
6. Explain the significance of screening and counselling for genetic disorders. (2016)
Screening and counseling for genetic disorders help identify at-risk individuals and provide information on disease risk, prevention, and management. Early detection through screening (e.g., newborn screening for metabolic disorders) can lead to timely interventions. Genetic counseling aids in understanding inheritance patterns, making informed reproductive choices, and managing genetic conditions. These practices improve health outcomes and reduce the burden of genetic diseases.
7. Down’s syndrome (10Marks 2015)
Down syndrome, or trisomy 21, is caused by an extra copy of chromosome 21. It leads to intellectual disability, characteristic facial features, and developmental delays. Individuals may also have congenital heart defects, respiratory and hearing problems, and a higher risk of certain medical conditions like thyroid disorders and leukemia. Early intervention and supportive care can improve quality of life.
8. Discuss chromosomal aberrations in man illustrating with examples. (15Marks 2015)
Chromosomal aberrations include numerical anomalies like Down syndrome (trisomy 21) and structural anomalies like Cri-du-chat syndrome (deletion on chromosome 5). Turner syndrome (45,X) and Klinefelter syndrome (47,XXY) are sex chromosome anomalies. These aberrations cause a range of physical, developmental, and intellectual disabilities, illustrating the critical role of chromosomal integrity in human health.
9. Describe Turner and Klinefelter Syndromes (15Marks 2014)
Turner syndrome (45,X) affects females, causing short stature, webbed neck, and infertility. Klinefelter syndrome (47,XXY) affects males, resulting in tall stature, hypogonadism, and learning difficulties. Both syndromes result from sex chromosome abnormalities, with Turner syndrome involving the loss of an X chromosome and Klinefelter syndrome involving an extra X chromosome.
10. Genetic Counselling (10Marks 2014) (12Marks 2012)
Genetic counseling provides information and support to individuals and families affected by genetic disorders. It involves assessing the risk of inherited conditions, explaining inheritance patterns, discussing testing options, and helping clients make informed decisions. Counselors address emotional and psychological impacts, guide preventive measures, and assist in managing genetic conditions.
11. Discuss the chromosomal aberrations and manifestations of Klinefelter and Turner syndromes (20Marks 2013)
Klinefelter syndrome (47,XXY) involves an extra X chromosome in males, causing hypogonadism, infertility, and learning difficulties. Turner syndrome (45,X) involves the loss of an X chromosome in females, leading to short stature, webbed neck, and infertility. Both syndromes result from sex chromosome abnormalities, impacting physical development, reproductive health, and cognitive function.
12. Chromosomal deletions and numerical fluctuations may lead to gross abnormalities in man. Discuss with the help of suitable example. (30 Marks — 2010)
Chromosomal deletions, like in Cri-du-chat syndrome (deletion on chromosome 5), cause intellectual disability and physical abnormalities. Numerical fluctuations, like in Down syndrome (trisomy 21), lead to intellectual disability and characteristic physical features. These aberrations disrupt normal development, causing significant health and developmental issues. Early diagnosis and intervention are crucial for management.
13. Discuss different types of sex chromosomal aberrations. (L.Q -2007)
Sex chromosomal aberrations include Turner syndrome (45,X), Klinefelter syndrome (47,XXY), Triple X syndrome (47,XXX), and XYY syndrome (47,XYY). Turner syndrome causes short stature and infertility in females. Klinefelter syndrome results in hypogonadism and learning difficulties in males. Triple X syndrome and XYY syndrome generally cause milder symptoms, such as tall stature and learning disabilities. These aberrations arise from errors in meiotic division.
14. What is Genetic Counselling? Discuss its relevance in the present day context. (L.Q - 2006)
Genetic counseling involves assessing the risk of inherited disorders, explaining inheritance patterns, and providing information and support to affected individuals and families. It helps in making informed reproductive choices, understanding genetic risks, and managing genetic conditions. In the present day, with advancements in genetic testing and personalized medicine, genetic counseling is crucial for preventing and managing genetic disorders, improving health outcomes, and addressing ethical, legal, and social implications of genetic information.
15. Klinefelter Syndrome (S.N - 2003)
Klinefelter syndrome (47,XXY) is a sex chromosome disorder in males, caused by an extra X chromosome. It results in hypogonadism, infertility, tall stature, and learning difficulties. Affected individuals may have reduced muscle mass, breast development, and less body hair. Early diagnosis and hormonal treatment can improve quality of life and mitigate some symptoms.
16. Genetic counselling (S.N - 2002)
Genetic counseling provides risk assessment, information, and support to individuals and families with genetic disorders. It helps understand inheritance patterns, discusses testing options, and aids in making informed decisions about health and reproduction. Counselors address emotional and psychological impacts, guide preventive measures, and assist in managing genetic conditions, enhancing patient care and outcomes.
17. Discuss the relevance of human DNA profiling and Gene Mapping in the prevention and cure of diseases. (L.Q -2001)
Human DNA profiling and gene mapping are crucial for identifying genetic predispositions to diseases, enabling early diagnosis and personalized treatment plans. DNA profiling helps in forensic investigations and paternity testing. Gene mapping locates genes associated with diseases, guiding targeted therapies and drug development. These technologies enhance disease prevention, improve patient care, and advance medical research.
18. Genetic Counselling (S.N - 1998)
Genetic counseling involves assessing genetic risks, providing information, and supporting individuals and families affected by genetic disorders. It helps in making informed reproductive choices, understanding genetic conditions, and managing health risks. Counselors address emotional and psychological impacts, guide preventive measures, and assist in navigating genetic information, enhancing patient care and decision-making.
19. Gene therapy (S.N - 1995)
Gene therapy involves introducing, removing, or altering genetic material within a person’s cells to treat or prevent diseases. It can correct defective genes responsible for disease development, offering potential cures for genetic disorders like cystic fibrosis, hemophilia, and certain cancers. Gene therapy holds promise for personalized medicine, providing targeted and effective treatments, but also poses ethical and technical challenges.
20. Discuss genetic and clinical aspects of the anomalies of sex chromosomes in man with Special reference to the associated mosaic constitutions (L.Q - 1995)
Anomalies of sex chromosomes include Turner syndrome (45,X) and Klinefelter syndrome (47,XXY). Mosaicism, where some cells have different chromosome numbers (e.g., 45,X/46,XX in Turner syndrome), can lead to varied clinical presentations. Turner syndrome causes short stature, infertility, and cardiovascular issues, while Klinefelter
1. Race and Ethnicity. 10M-2023
Race refers to the categorization of humans based on physical characteristics such as skin color, hair texture, and facial features. Ethnicity relates to cultural factors, including nationality, culture, language, and ancestry. While race is often seen as a biological concept, ethnicity encompasses social and cultural identities. Understanding both concepts is crucial for addressing issues of identity, diversity, and social inequality.
2. Is race a valid and biologically meaningful concept? (10 Marks, 2021)
Race is not considered a valid biological concept as genetic differences among human populations are minimal and do not correspond to traditional racial classifications. Human genetic diversity is continuous and does not fit into discrete categories. Modern anthropology and genetics emphasize that race is a social construct with no scientific basis, reflecting historical and sociopolitical contexts rather than biological reality.
3. Racism and Eugenics. 10 M (2020)
Racism is the belief that certain races are superior or inferior to others, leading to discrimination and prejudice. Eugenics is a pseudoscientific movement aimed at improving the genetic quality of the human population by selective breeding. Both racism and eugenics have been discredited scientifically but have had devastating social and ethical consequences, including the justification of atrocities like the Holocaust and systemic discrimination.
4. With reference to the somatoscopic and morphometric characteristics commonly used for racial classification, make critical comments as to whether ‘Race’ is a valid concept. 20 marks (2019)
Somatoscopic (observational) and morphometric (measurement-based) characteristics, such as skin color, skull shape, and body measurements, have historically been used to classify races. However, these characteristics show continuous variation and significant overlap among populations. Genetic research has shown that most human variation occurs within populations rather than between them. Thus, racial classifications based on these characteristics are scientifically invalid and reflect social constructs rather than biological realities.
5. Race is a Myth. Justify its Present day Relevance. 10 M (2018)
The idea of race as a biologically distinct category is a myth, as genetic variation within so-called racial groups is greater than between them. Despite its lack of scientific validity, race remains relevant today due to its profound social, cultural, and political impacts. Racial categories continue to influence identity, social interactions, and access to resources and opportunities. Addressing racial issues is essential for promoting social justice and equality.
6. Concept of race. 10 M (2017)
The concept of race historically referred to groups of people with shared physical traits and assumed common ancestry. Modern anthropology and genetics, however, view race as a social construct with no biological basis. Genetic diversity within human populations does not align with traditional racial categories. Instead, race is understood as a product of social, political, and historical contexts, shaping identities and experiences.
7. Explain the role of heredity and environment in the formation of races. 15 M (2016)
Heredity and environment both influence human variation. Heredity determines genetic traits passed from parents to offspring, while the environment shapes these traits through factors like climate, diet, and cultural practices. Over time, populations adapt to their environments, resulting in physical and genetic differences. However, these variations are gradual and do not support the rigid racial classifications historically used. Instead, they illustrate the dynamic interplay between genetics and environment in human diversity.
8. Differentiate between Race and Racism. What are three major races of the world? Give important biological criteria used frequently for such a classification. (15Marks 2013)
Race refers to the categorization of humans based on perceived physical differences, while racism is the belief in the superiority of one race over others, leading to discrimination. The three major races historically classified are Caucasoid, Mongoloid, and Negroid. Biological criteria for these classifications included skin color, hair type, and facial features. However, these classifications are outdated and scientifically invalid, as genetic research shows more variation within these groups than between them.
9. Discuss race crossing in humans with suitable examples (20Marks 2012)
Race crossing refers to the mixing of individuals from different racial backgrounds through intermarriage or reproduction. Examples include the mixed-race populations in Latin America (e.g., Mestizos of European and Native American ancestry) and the United States (e.g., African American communities with diverse ancestries). Genetic studies show that race crossing increases genetic diversity and challenges the validity of strict racial classifications, demonstrating the fluidity and interconnectedness of human populations.
10. Is Race a valid concept? Critically assess the relevance of racial classification in the Indian Context. (30 Marks — 2010)
Race is not a valid biological concept, as genetic research reveals more variation within populations than between them. In the Indian context, traditional racial classifications (e.g., Aryan, Dravidian) are based on outdated anthropological theories and do not reflect genetic realities. India’s diverse population results from complex historical migrations and cultural exchanges. Modern genetics emphasizes the fluidity of human variation, making rigid racial classifications irrelevant. Instead, social and cultural identities should be recognized and respected.
11. Racial Criteria (S.N-2006)
Racial criteria historically included physical characteristics such as skin color, hair type, facial features, and body measurements. These criteria were used to classify humans into distinct racial groups. However, modern anthropology and genetics have debunked the validity of these criteria, showing that human variation is continuous and does not align with discrete racial categories. Racial classifications are now understood as social constructs rather than biological realities.
12. Race & Racism (S.N - 2004)
Race is a social construct used to categorize humans based on perceived physical differences. Racism is the belief in the superiority of one race over others, leading to discrimination and prejudice. While race lacks scientific validity, racism has profound social and political impacts, perpetuating inequality and injustice. Addressing racism requires recognizing the social nature of race and promoting equality and diversity.
13. What is ‘race? Enumerate and discuss the factors responsible for the formation of races. (S.N 1998)
Race is a social construct used to categorize humans based on perceived physical differences. Factors historically thought to form races include geographic isolation, natural selection, genetic drift, and cultural practices. However, modern genetics reveals that human variation is continuous and not aligned with these racial categories. Environmental and cultural adaptations shape human diversity, challenging the validity of race as a biological concept.
14. Controversies of race (S.N - 1996)
The concept of race is controversial due to its lack of scientific validity and its use to justify discrimination and inequality. Genetic research shows that human variation does not fit into discrete racial categories, undermining the biological basis of race. Social and political implications of race, such as systemic racism and historical injustices, further complicate the concept. Addressing these controversies requires recognizing race as a social construct and promoting equality and diversity.
