El Nino effect is leading to increased melting of polar ice caps as well as of other snow caps. Suggest a process by which both these problems can be addressed. As the female partner is having a blockage in the fallopian tube, In vitro fertilization, followed by embryo transfer (ET) will help her conceive. As the female partner is having a blockage in the fallopian tube, In vitro fertilization, followed by embryo transfer (ET) will help her conceive. CBSE Board Exam 2020: The CBSE Class 12 Board exams have commences from February and the Biology exam is scheduled for March 14, 2020. Klinefelter’s Syndrome: This is caused due to the presence of an additional copy of X-chromosome resulting in a karyotype of 47, XXY. ‘Parturition is induced by a complex Neuroendocrine mechanism.’ Justify. Check important questions & answers for CBSE Class 12th Biology Board Exam 2020. In Vallisneria, the female flower reaches the surface of the water by the long stalk and the male flowers or pollen grains are released on to the surface of the water. b) How lane one is different from lane 2, 3 and 4 in the Gel electrophoresis set up? The students who are appearing for CBSE Class 12th Biology Examination can go through the important questions mentioned in this article. bacteria with the plasmid inside the bacteria are cultured on a large scale in an industrial fermenter which then synthesizes its protein. AIDS caused by the Human Immunodeficiency Virus. Carbon monoxide and nitric oxides are changed to carbon dioxide and nitrogen gas respectively. There is an alarming increase in lifestyle diseases in India in addition to the large scale malnutrition. c. The changes that occur when an ovule matures into a seed are: i) Integuments of ovules harden as tough protective seed coats. Carbon monoxide and nitric oxides are changed to carbon dioxide and nitrogen gas respectively. a) Bacteriophages, as it has very high copy numbers of their genome within the bacterial cells whereas some plasmids may have only one or two copies per cell and others may have 15-100 copies per cell. Failure of segregation of chromatids during cell division cycle results in the gain or loss of a chromosome(s) ( aneuploidy). question numbers 1 to 5, multiple choice questions of one mark each. HSC Board Exams are fast approaching and students are getting anxious about how to prepare for their HSC Board Exams. Question 47- “ Indiscriminate human activities have strengthened the greenhouse effect resulting in Global Warming.” Give the relative contribution of various Green House Gases and explain the fate of the energy of sunlight reaching the earth’s surface contributing to Global Warming. Answer: a) Chemical evolution – The first form of life originated from pre-existing non-living organic molecules. with three dominant alleles and three recessive alleles. The students will find these questions helpful while preparing for the upcoming Class 12th Biology Examination 2020. Unleaded petrol is the best fuel for such vehicles. a. Nature’s way of transferring energy fixed by plants to higher trophic levels/conduits for energy transfer. They are carried passively by water currents some of them eventually reach the female flowers and the stigma. CBSE Class 12 Biology Chapter-wise Notes presented by Vidyakul offer students with the summary of the chapters, important points to remember, detailed explanation of important concepts and illustrations for better comprehension and retaining of the chapter content. Important Questions for Class 12 Chapter 10: Microbes in Human Welfare Microbes are tiny structures that are not visible to the naked eye, they are microscopic in nature. It is important that all garbage generated is sorted. In this case, sperms from the male partner will be collected and injected into the ovum of the female partner to form zygote under simulated conditions in the laboratory and embryo with more than 8 blastomeres will be transferred into the uterus IUT – intrauterine transfer, to complete its further development. questions and five sections in the question paper. What is mutation breeding? It will boost the confidence of students to perform better in the NIOS Class XII Exam. Tag: class 12 biology most important questions 2020. Maharashtra Board of Secondary and Higher Secondary Education, Pune has announced class 11th and 12th standard sample model question paper with answer solutions for general and vocational course Arts, Science, and Commerce stream Marathi medium, Hindi medium, English medium students for Theory, Objective, and Multiple choice questions to the academic year of 2021. Question 1- Which cells are responsible for the synthesis of Androgens? A primary spermatocyte completes the first meiotic division leading to the formation of two equal-sized secondary spermatocytes whereas, Primary oocyte divides unequally by the first meiotic division resulting in the formation of a large haploid secondary oocyte and a tiny first polar body. Check important questions and answers for CBSE Class 12 Biology board exam 2020. Answer: a. compulsory. 5. Meritnation|Feb 19th, 2016 05:01pm. These MCQ's are extremely critical for all CBSE students to score better marks. abilities among students, produce better results and improve the AIDS caused by the Human Immunodeficiency Virus. State the Mendelian principle which can be derived from a dihybrid cross and not from monohybrid cross. Our experts have pointed out these questions after the analysis of previous years' papers, latest syllabus & sample paper. all the short and long answer … b. psychological barriers are the acid in the stomach and saliva in the mouth. This website uses cookie or similar technologies, to enhance your browsing experience and provide personalised recommendations. Measures that could be taken are: We can support the government’s initiative across the country by reducing the use of plastics and the use of eco-friendly packaging. Inbreeding is necessary if we want to evolve a pure line in any animal. The unit begins with the 8th chapter of NCERT biology class 12th textbook “Human Health and Diseases,” and the important topics for CBSE board exam 2020 are:- Pathogen Causing Human Diseases, Basic Concepts of Immunology, Cancer, HIV & AIDS, Adolescence- Drug and Alcohol Abuse and can constitute questions of 1, 2, 3, or 5 marks in the … Answer: The thymus provides micro-environments for the development and maturation of T lymphocytes. NCERT Solutions 2020-21 for other subjects Physics, Chemistry, Maths are also available to download. Vaccines prevent microbial infections by initiating production of antibodies against these antigens to neutralise the pathogenic agents during later actual infection. Klinefelter’s Syndrome: The affected individual is a male with the development of breast, i.e., Gynecomastia. Answer: After the addition of lactose, a complete breakdown of lactose to glucose and galactose takes place. with three dominant alleles and three recessive alleles. It leaves only the nonbiodegradable to be disposed of, the quantity of which should be minimized. 0. Answer: (a) To maintain the cells in their physiologically most active log/exponential phase. Top. Which cells are responsible for the synthesis of Androgens? “ Indiscriminate human activities have strengthened the greenhouse effect resulting in Global Warming.” Give the relative contribution of various Green House Gases and explain the fate of the energy of sunlight reaching the earth’s surface contributing to Global Warming. b. Parturition is a process where vigorous contraction of the uterus at the end of pregnancy causes expulsion/delivery of the foetus. Subject wise and topic wise. A biotechnologist wanted to create a colony of E.coli possessing the plasmid pBR322, sensitive to Tetracycline. Describe one example each of chromosomal disorder along with the symptoms involving an autosome and a sex chromosome. sufficient to score 80%+ by just doing these questions. Firstly, know the breakdown of the chapters/units. b) Vitamin Enriched - Vitamin A Enriched Carrots, Spinach, Pumpkin. Ex-situ Conservation –Threatened animals and plants are taken out from their natural habitat and placed in a setting where they can be protected and given care Examples - in botanical gardens, zoological gardens, seed, pollen, gene banks. The third unit of NCERT biology class 12th textbook is “Biology and Human Welfare,” and has a weightage of 14 marks, including three chapters. The Board will conduct the CBSE Class 12 Biology paper on March 14. It is an asexually reproduced mass of cells, that is capable of developing into a new organism. If you are looking for the important question of AHSEC class 12 Biology 2020. Give an example of a crop and the disease to which resistance was induced by mutation. Latest CBSE Sample Papers for Class 12 Biology 2019-2020 in PDF form free download. Answer: a) Each primary spermatocyte will undergo meiosis-I and meiosis-2 which will result in 4 spermatozoa 300 million/4=75 million, b) Since replication has occurred by this stage 46x2 = 92 chromatids, c) Meiosis –I is completed by this time 92/2 =46 chromatids. Choose the correct reasons for Rheumatoid arthritis for the following: More antibodies are produced in the body. a. Palm is broad with characteristic palm crease. This chapter contains all type of questions i.e. The genotype with all dominant alleles (AABBCC) will be darkest skin colour and with recessive alleles will be light test skin colour (aabbcc). d) Predict the consequences when both the template and the coding strands of a DNA segment participate in the transcription process? L.S of a chromosome ( s ) ( Aneuploidy ) year question papers & Solutions mp... Oswaal & Super 20 free PDF download Online was found dead off coast. 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