{"id":40651,"date":"2024-05-03T06:41:44","date_gmt":"2024-05-03T06:41:44","guid":{"rendered":"https:\/\/edukemy.com\/blog\/?p=40651"},"modified":"2024-05-03T06:41:44","modified_gmt":"2024-05-03T06:41:44","slug":"upsc-prelims-topic-wise-questions-biology-genetics-and-evolution","status":"publish","type":"post","link":"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/","title":{"rendered":"UPSC Prelims Topic Wise Questions &#8211; Biology &#8211; Genetics and Evolution"},"content":{"rendered":"\n<figure class=\"wp-block-image size-full is-resized\"><a href=\"https:\/\/edukemy.com\/upsc\/upsc-prelims-test-series?utm_source=Blog&amp;utm_medium=Blog&amp;utm_campaign=Blog-%20PTS\" target=\"_blank\" rel=\"noreferrer noopener\"><img fetchpriority=\"high\" decoding=\"async\" src=\"https:\/\/edukemy.com\/blog\/wp-content\/uploads\/2024\/02\/Prelims-Test-Series-eng-and-hindi-1280\u00d7330.svg\" alt=\"UPSC Prelims Mock Test - ECONOMY 2\" class=\"wp-image-24924\" width=\"779\" height=\"199\"\/><\/a><\/figure>\n\n\n\n<p>Preparing for the UPSC Prelims can be an arduous task, especially when it comes to mastering the intricacies of biology, particularly genetics and evolution. In this realm, understanding the fundamental principles and the intricate nuances of genetic inheritance, mutation, natural selection, and the broader mechanisms of evolution is paramount. The UPSC Prelims Topic Wise Questions in Biology delve deep into these subjects, challenging aspirants to not only grasp theoretical concepts but also to apply them in real-world scenarios. With a blend of theoretical knowledge and practical understanding, aspirants can navigate through these questions, laying a strong foundation for success in the competitive examination.<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_73 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<label for=\"ez-toc-cssicon-toggle-item-69d3e9dc1f0fe\" class=\"ez-toc-cssicon-toggle-label\"><p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-cssicon\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-69d3e9dc1f0fe\"  \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q1_Which_of_the_following_professionals_are_more_likely_to_run_the_risk_of_a_permanent_change_in_their_cells_DNA_1996\" title=\"Q1. Which of the following professional(s) are more likely to run the risk of a permanent change in their cell&#8217;s DNA? (1996)\">Q1. Which of the following professional(s) are more likely to run the risk of a permanent change in their cell&#8217;s DNA? (1996)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_b\" title=\"Ans. (b)\">Ans. (b)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q2_Haemophilia_is_a_genetic_disorder_which_leads_to\" title=\"Q2. Haemophilia is a genetic disorder which leads to\">Q2. Haemophilia is a genetic disorder which leads to<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_d\" title=\"Ans. (d)\">Ans. (d)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q3_Match_List-I_with_List_II_and_select_the_correct_using_the_codes_given_below_the_lists_1998\" title=\"Q3. Match List-I with List II and select the correct using the codes given below the lists: (1998)\">Q3. Match List-I with List II and select the correct using the codes given below the lists: (1998)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_b-2\" title=\"Ans. (b)\">Ans. (b)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q4_Which_one_of_the_following_genetic_diseases_is_sex-linked_1999\" title=\"Q4. Which one of the following genetic diseases is sex-linked? (1999)\">Q4. Which one of the following genetic diseases is sex-linked? (1999)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_a\" title=\"Ans. (a)\">Ans. (a)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q5\" title=\"Q5.\">Q5.<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_d-2\" title=\"Ans. (d)\">Ans. (d)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q6_In_the_context_of_organic_evolution_the_loss_of_limbs_in_snakes_is_explained_by_the_phenomenon_of_2002\" title=\"Q6. In the context of organic evolution, the loss of limbs in snakes is explained by the phenomenon of (2002)\">Q6. In the context of organic evolution, the loss of limbs in snakes is explained by the phenomenon of (2002)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_a-2\" title=\"Ans. (a)\">Ans. (a)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q7_When_one_gene_controls_two_or_more_different_characters_simultaneously_the_phenomenon_is_called_2002\" title=\"Q7. When one gene controls two or more different characters simultaneously, the phenomenon is called (2002)\">Q7. When one gene controls two or more different characters simultaneously, the phenomenon is called (2002)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_b-3\" title=\"Ans. (b)\">Ans. (b)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q9_Among_living_organisms_which_one_of_the_following_is_the_most_responsible_factor_for_bringing_about_the_origin_of_a_new_species_2002\" title=\"Q9. Among living organisms, which one of the following is the most responsible factor for bringing about the origin of a new species? (2002)\">Q9. Among living organisms, which one of the following is the most responsible factor for bringing about the origin of a new species? (2002)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_a-3\" title=\"Ans. (a)\">Ans. (a)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q10_Which_of_the_following_features_of_DNA_makes_it_uniquely_suited_to_store_and_transmit_genetic_information_from_generation_to_generation_2002\" title=\"Q10. Which of the following features of DNA makes it uniquely suited to store and transmit genetic information from generation to generation? (2002)\">Q10. Which of the following features of DNA makes it uniquely suited to store and transmit genetic information from generation to generation? (2002)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_a-4\" title=\"Ans. (a)\">Ans. (a)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-19\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q11_Match_List_I_with_List_II_and_select_the_correct_answer_using_the_codes_given_below_2002\" title=\"Q11. Match List I with List II and select the correct answer using the codes given below (2002)\">Q11. Match List I with List II and select the correct answer using the codes given below (2002)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-20\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_d-3\" title=\"Ans. (d)\">Ans. (d)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-21\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q12_Among_the_following_which_one_is_not_an_ape_2008\" title=\"Q12. Among the following, which one is not an ape? (2008)\">Q12. Among the following, which one is not an ape? (2008)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-22\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_c\" title=\"Ans. (c)\">Ans. (c)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-23\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Q13_Nobel_Prize_winning_scientist_James_D_Watson_is_known_for_his_work_in_which_area_2008\" title=\"Q13. Nobel Prize winning scientist James D Watson is known for his work in which area? (2008)\">Q13. Nobel Prize winning scientist James D Watson is known for his work in which area? (2008)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-24\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Ans_d-4\" title=\"Ans. (d)\">Ans. (d)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-25\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#In_case_you_still_have_your_doubts_contact_us_on_9811333901\" title=\"In case you still have your doubts, contact us on 9811333901.&nbsp;\">In case you still have your doubts, contact us on 9811333901.&nbsp;<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-26\" href=\"https:\/\/edukemy.com\/blog\/upsc-prelims-topic-wise-questions-biology-genetics-and-evolution\/#Visit_our_YouTube_Channel_%E2%80%93_here\" title=\"Visit our YouTube Channel &#8211;&nbsp;here\">Visit our YouTube Channel &#8211;&nbsp;here<\/a><\/li><\/ul><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q1_Which_of_the_following_professionals_are_more_likely_to_run_the_risk_of_a_permanent_change_in_their_cells_DNA_1996\"><\/span>Q1. Which of the following professional(s) are more likely to run the risk of a permanent change in their cell&#8217;s DNA? (1996) <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>1. Researchers using carbon-14 isotope <\/p>\n\n\n\n<p>2. X-ray technician <\/p>\n\n\n\n<p>3. Coal miner <\/p>\n\n\n\n<p>4. Dyer and painter <\/p>\n\n\n\n<p>Select the correct answer using the codes given below <\/p>\n\n\n\n<p>(a) Only 2 <\/p>\n\n\n\n<p>(b) 1, 2 and 3 <\/p>\n\n\n\n<p>(c) 1, 2 and 4 <\/p>\n\n\n\n<p>(d) 1, 3 and 4 <\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_b\"><\/span>Ans. (b)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>The Carbon-14 isotope, X-ray technicians, and coal miners are all susceptible to a potential permanent alteration in their DNA. X-rays possess the capacity to harm cells and tissues, potentially inducing mutations. Excessive exposure to X-rays can result in cellular damage and increase the risk of cancer. Researchers utilizing C-14 isotopes and coal miners, even when exposed to lower concentrations of radiation over time, face the prospect of DNA mutations.<\/p>\n\n\n\n<p>Conversely, dyers and painters are not subject to the same risk of permanent DNA alteration. Paints and dyes typically do not contain mutagens, thus reducing the likelihood of cellular mutations in these professions.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q2_Haemophilia_is_a_genetic_disorder_which_leads_to\"><\/span>Q2. Haemophilia is a genetic disorder which leads to <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>(a) decrease in haemoglobin level <\/p>\n\n\n\n<p>(b) rheumatic heart disease <\/p>\n\n\n\n<p>(c) decrease in WBC <\/p>\n\n\n\n<p>(d) non-clotting of blood <\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_d\"><\/span>Ans. (d)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Hemophilia, a genetic disorder, disrupts the blood clotting process, leading to prolonged bleeding. This condition is caused by a recessive gene on the X chromosome, meaning it manifests when the dominant gene is absent. Consequently, it primarily affects males who inherit the gene from carrier females. The disorder impacts a key protein crucial for clotting, causing even minor injuries to result in persistent bleeding in affected individuals.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q3_Match_List-I_with_List_II_and_select_the_correct_using_the_codes_given_below_the_lists_1998\"><\/span>Q3. Match List-I with List II and select the correct using the codes given below the lists: (1998) <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>List I &#8211; List II <\/p>\n\n\n\n<p>A. Theory of mutation &#8211; 1. Beadle and Tatum<\/p>\n\n\n\n<p>B. Theory of evolution &#8211; 2. Jacob and Monod<\/p>\n\n\n\n<p>C. One gene one enzyme hypothesis &#8211; 3. Darwin <\/p>\n\n\n\n<p>D. Operon concept &#8211; 4. de vries <\/p>\n\n\n\n<p>Codes <\/p>\n\n\n\n<p>ABCD <\/p>\n\n\n\n<p>(a) 3 4 1 2 <\/p>\n\n\n\n<p>(b)4 3 1 2 <\/p>\n\n\n\n<p>(c) 4 3 2 1<\/p>\n\n\n\n<p>(d) 3 4 2 1<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_b-2\"><\/span>Ans. (b)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>The accurate pairing is as follows: A-4, B-3, C-1, D-2. The theory of mutation was hypothesized by Hugo de Vries in 1901. Darwin proposed the theory of evolution in the 19th century. Beadle and Tatum formulated the one gene one enzyme hypothesis following their experiments on Neurospora crassa. The concept of operon was introduced by Jacob and Monod.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q4_Which_one_of_the_following_genetic_diseases_is_sex-linked_1999\"><\/span>Q4. Which one of the following genetic diseases is sex-linked? (1999) <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>(a) Royal haemophilia <\/p>\n\n\n\n<p>(b) Tay-Sachs disease <\/p>\n\n\n\n<p>(c) Cystic fibrosis <\/p>\n\n\n\n<p>(d) Hypertension<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_a\"><\/span>Ans. (a) <span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Royal hemophilia, also known as the &#8220;Royal disease,&#8221; is a sex-linked condition that has been notably prevalent among European royal families. It traces its spread back to Queen Victoria&#8217;s descendants (1819-1901). This condition, characterized by impaired blood clotting, is a recessive trait linked to the X chromosome. In contrast, Tay-Sachs disease, an autosomal recessive disorder, is located on non-sex chromosomes.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q5\"><\/span>Q5. <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Assertion (A) In human beings, the female plays a major role in determining the sex of the offspring. <\/p>\n\n\n\n<p>Reason (R) Women have two &#8216;X&#8217;-chromosomes. (2000) <\/p>\n\n\n\n<p>Codes <\/p>\n\n\n\n<p>(a) Both A and R are true and R is the correct explanation of A <\/p>\n\n\n\n<p>(b) Both A and R are true, but R is not a correct explanation of A <\/p>\n\n\n\n<p>(c) A is true, but R is false <\/p>\n\n\n\n<p>(d) A is false, but R is true <\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_d-2\"><\/span>Ans. (d)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Assertion: Exp. A is false, but R is true. The assertion can be corrected as follows: In human beings, males play the major role in determining the sex of the offspring because they carry both X and Y chromosomes, whereas females carry two X chromosomes. Therefore, it is the sperm, whether carrying an X or Y chromosome, that fuses with the egg and determines the sex of the fetus.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q6_In_the_context_of_organic_evolution_the_loss_of_limbs_in_snakes_is_explained_by_the_phenomenon_of_2002\"><\/span>Q6. In the context of organic evolution, the loss of limbs in snakes is explained by the phenomenon of (2002)<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>(a) use and disuse of organs<\/p>\n\n\n\n<p>(b) adaptation to living in burrows <\/p>\n\n\n\n<p>(c) natural selection <\/p>\n\n\n\n<p>(d) inheritance of acquired characters <\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_a-2\"><\/span>Ans. (a)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>In the realm of organic evolution, the absence of limbs in snakes is elucidated by the principle of organ use and disuse. Lamarck posited that in evolution, body parts utilized more frequently tend to strengthen and improve, whereas those underutilized or unused tend to diminish over time. Hence, the loss of limbs in snakes exemplifies the concept of organ use and disuse.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q7_When_one_gene_controls_two_or_more_different_characters_simultaneously_the_phenomenon_is_called_2002\"><\/span>Q7. When one gene controls two or more different characters simultaneously, the phenomenon is called (2002) <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>(a) apomixis <\/p>\n\n\n\n<p>(b) pleiotropy <\/p>\n\n\n\n<p>(c) polyploidy <\/p>\n\n\n\n<p>(d) polyteny <\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_b-3\"><\/span>Ans. (b)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Pleiotropy occurs when a single gene governs multiple distinct traits concurrently. This phenomenon, exemplified by conditions like Tay-Sachs disease, demonstrates how one genetic element can impact various characteristics simultaneously.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q9_Among_living_organisms_which_one_of_the_following_is_the_most_responsible_factor_for_bringing_about_the_origin_of_a_new_species_2002\"><\/span>Q9. Among living organisms, which one of the following is the most responsible factor for bringing about the origin of a new species? (2002) <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>(a) Isolation <\/p>\n\n\n\n<p>(c) Natural selection <\/p>\n\n\n\n<p>(b) Mutation <\/p>\n\n\n\n<p>(d) Sexual reproduction <\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_a-3\"><\/span>Ans. (a)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>The primary catalyst for the emergence of new species is isolation. Speciation, the process through which new and distinct species evolve, entails the division of a single evolutionary lineage into multiple genetically independent ones. There are two principal forms of speciation:<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>Allopatric speciation arises from geographical isolation, leading to the subsequent divergence of separated populations due to factors like genetic drift or natural selection.<\/li><li>Sympatric speciation occurs through ecological isolation, where populations diverge within the same geographic area, often driven by rapid chromosomal changes like polyploidy.<\/li><\/ol>\n\n\n\n<p>While factors like mutation, natural selection, and sexual reproduction contribute to species variation, isolation stands out as the most crucial factor in initiating the formation of new species among the provided options.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q10_Which_of_the_following_features_of_DNA_makes_it_uniquely_suited_to_store_and_transmit_genetic_information_from_generation_to_generation_2002\"><\/span>Q10. Which of the following features of DNA makes it uniquely suited to store and transmit genetic information from generation to generation? (2002) <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>(a) Complementrity of the two strands <\/p>\n\n\n\n<p>(b) Double helix <\/p>\n\n\n\n<p>(c) Number of base-pairs per turn <\/p>\n\n\n\n<p>(d) Sugar-phosphate backbone<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_a-4\"><\/span>Ans. (a)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>The distinctive attribute of DNA, enabling it to efficiently store and pass on genetic information across generations, lies in the complementary nature of its two strands. To safeguard against degradation by cytoplasmic enzymes, DNA possesses the remarkable ability of replication, ensuring the faithful production of carbon copies. This process is vital for the seamless transfer of genetic material from parent cells to their offspring and perpetuates the transmission of information from one generation to the next.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q11_Match_List_I_with_List_II_and_select_the_correct_answer_using_the_codes_given_below_2002\"><\/span>Q11. Match List I with List II and select the correct answer using the codes given below (2002) <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>List I (Achievement in Genetics) List II (Scientists) <\/p>\n\n\n\n<p>A. Discovery of transduction and conjugation in bacteria 1. Khorana <\/p>\n\n\n\n<p>B. Establishing the sex-linked inheritance 2. Komberg<\/p>\n\n\n\n<p>C. Isolation of DNA polymerase from Ecoli 3. Lederberg <\/p>\n\n\n\n<p>D Establishing the complete genetic code 4. Morgan <\/p>\n\n\n\n<p>5. Ochoa <\/p>\n\n\n\n<p>Codes <\/p>\n\n\n\n<p>ABCD <\/p>\n\n\n\n<p>(a) 4 3 2 1 <\/p>\n\n\n\n<p>(b) 3 4 2 5 <\/p>\n\n\n\n<p>(c) 4 3 1 5<\/p>\n\n\n\n<p>(d) 3 4 2 1 <\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_d-3\"><\/span>Ans. (d) <span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>The accurate pairings are: A-3, B-4, C-2, D-1. Lederberg (1952) unveiled the discoveries of transduction and conjugation in bacteria, while T.H. Morgan popularized theories on sex-linked inheritance around 1808. Arthur Kornberg isolated DNA polymerase from E. coli, and Har Gobind Khorana elucidated the complete genetic code, a set of three-letter nucleotide combinations, earning him the Nobel Prize in 1968.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q12_Among_the_following_which_one_is_not_an_ape_2008\"><\/span>Q12. Among the following, which one is not an ape? (2008)<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>(a) Gibbon <\/p>\n\n\n\n<p>(b) Gorilla <\/p>\n\n\n\n<p>(c) Langur <\/p>\n\n\n\n<p>(d) Orangutan<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_c\"><\/span>Ans. (c) <span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Among these options, langurs are not classified as apes. Grey langurs, a collective of Old World monkeys, constitute the entire genus Semnopithecus.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Q13_Nobel_Prize_winning_scientist_James_D_Watson_is_known_for_his_work_in_which_area_2008\"><\/span>Q13. Nobel Prize winning scientist James D Watson is known for his work in which area? (2008) <span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>(a) Metallurgy <\/p>\n\n\n\n<p>(b) Meteorology <\/p>\n\n\n\n<p>(c) Environmental protection <\/p>\n\n\n\n<p>(d) Genetics <\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Ans_d-4\"><\/span>Ans. (d)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Renowned Nobel laureate James D. Watson made indelible contributions to the field of genetics, particularly renowned for his groundbreaking discovery of the DNA molecule, symbolized by its initials. Together with his collaborator Francis Crick, they unveiled the elegant double helix model, a revelation that echoed globally. This seminal work revolutionized the study of biology and the genetics of DNA molecules, laying the groundwork for modern biotechnology practices such as recombinant DNA techniques. In acknowledgment of their pioneering achievement, Watson and Crick were jointly awarded the 1962 Nobel Prize in Physiology and Medicine, alongside Maurice Wilkins.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><a href=\"https:\/\/edukemy.com\/upsc\/upsc-essay?utm_source=Blog&amp;utm_medium=Banner&amp;utm_campaign=Essay\" target=\"_blank\" rel=\"noreferrer noopener\"><img decoding=\"async\" data-src=\"https:\/\/edukemy.com\/blog\/wp-content\/uploads\/2024\/06\/UPSC-Essay-Course-1280\u00d7300-1-3.svg\" alt=\"\" class=\"wp-image-42688 lazyload\" width=\"781\" height=\"182\" src=\"data:image\/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==\" style=\"--smush-placeholder-width: 781px; --smush-placeholder-aspect-ratio: 781\/182;\" \/><\/a><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"In_case_you_still_have_your_doubts_contact_us_on_9811333901\"><\/span><strong>In case you still have your doubts, contact us on 9811333901.<\/strong>&nbsp;<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>For UPSC Prelims Resources,&nbsp;<a href=\"https:\/\/edukemy.com\/upsc-cse-prelims-resource-centre\" target=\"_blank\" rel=\"noreferrer noopener\">Click here<\/a><\/p>\n\n\n\n<p>For Daily Updates and Study Material:<\/p>\n\n\n\n<p>Join our Telegram Channel &#8211;&nbsp;<a href=\"https:\/\/t.me\/WithEdukemy4IAS\" target=\"_blank\" rel=\"noreferrer noopener\">Edukemy for IAS<\/a><\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>1. Learn through Videos &#8211;&nbsp;<a href=\"https:\/\/bit.ly\/3vOD8sU\" target=\"_blank\" rel=\"noreferrer noopener\">here<\/a><\/li><li>2. Be Exam Ready by Practicing Daily MCQs &#8211;&nbsp;<a href=\"https:\/\/bit.ly\/3Q9z2nF\" target=\"_blank\" rel=\"noreferrer noopener\">here<\/a><\/li><li>3. Daily Newsletter &#8211; Get all your Current Affairs Covered &#8211;&nbsp;<a href=\"https:\/\/bit.ly\/3bE2y5J\" target=\"_blank\" rel=\"noreferrer noopener\">here<\/a><\/li><li>4. Mains Answer Writing Practice &#8211;&nbsp;<a href=\"https:\/\/bit.ly\/3mZuVxl\" target=\"_blank\" rel=\"noreferrer noopener\">here<\/a><\/li><\/ul>\n\n\n\n<h4 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Visit_our_YouTube_Channel_%E2%80%93_here\"><\/span>Visit our YouTube Channel &#8211;&nbsp;<a href=\"https:\/\/www.youtube.com\/@EduKemyforIAS\">here<\/a><span class=\"ez-toc-section-end\"><\/span><\/h4>\n","protected":false},"excerpt":{"rendered":"<p>Preparing for the UPSC Prelims can be an arduous task, especially when it comes to mastering the intricacies of biology, particularly genetics and evolution. <\/p>\n","protected":false},"author":21,"featured_media":40653,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_eb_attr":"","om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"_lmt_disableupdate":"","_lmt_disable":"","footnotes":""},"categories":[3078],"tags":[232,231,179,3246,140],"class_list":["post-40651","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-upsc-prelims-topic-wise-question","tag-upsc","tag-upsc-prelims","tag-upsc-prelims-strategy","tag-upsc-prelims-topic-wise-questions","tag-upsc_preparation_strategy"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/posts\/40651","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/users\/21"}],"replies":[{"embeddable":true,"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/comments?post=40651"}],"version-history":[{"count":1,"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/posts\/40651\/revisions"}],"predecessor-version":[{"id":40660,"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/posts\/40651\/revisions\/40660"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/media\/40653"}],"wp:attachment":[{"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/media?parent=40651"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/categories?post=40651"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/edukemy.com\/blog\/wp-json\/wp\/v2\/tags?post=40651"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}