The CBSE class 12th Biology exam is quite tough, but if you have the list of important questions, you can attempt it with more confidence as you would have prepared it earlier. 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 CBSE Class 12th Biology Examination will be held on March 14, 2020. Question 36- When the gene product is required in large amounts, so transformed bacteria with the plasmid inside the bacteria are cultured on a large scale in an industrial fermenter which then synthesizes its protein. d. Alien species are highly invasive and are a threat to indigenous species. b. Question 10- What is the scientific name of the source organism through which the first antibiotic was produced? Examples- wildlife sanctuaries, national parks, biosphere reserves, sacred groves. June 1, 2020 June 18, 2020 Adarsh Barnwal 8 Comments on Class 12 Biology Important Question with Answer 2020 (adsbygoogle = window.adsbygoogle || []).push({}); Central Board of Secondary Education c. List the changes that occur when an ovule matures into a seed. Draw a labelled diagram of L.S of a pistil showing the passage of growing of. In this, Meristem apical or axillary is excised. CBSE Class 12 Biology Chapter-wise Notes PDF. Such individuals are sterile. June 1, 2020 June 18, 2020 Adarsh Barnwal 8 Comments on Class 12 Biology Important Question with Answer 2020 (adsbygoogle = window.adsbygoogle || []).push({}); Central Board of Secondary Education (CBSE), this year made some important changes in Read More… Recent Posts. Criteria for determining biodiversity hot spots are: Hotspots In India - the Western Ghats, Himalaya (Indo-Burma/Sunderland to be accepted). We can do our bit by carrying a cloth or other natural fibre carry-bags when we go for shopping and by refusing to take the polythene bags from shopkeepers. Here we have provided NCERT Exemplar Problems Solutions along with NCERT Exemplar Problems Class 12.. Answer: Keeping beehives in crop fields during the flowering period increases pollination efficiency and improves the yield– crop yield and honey yield. Answer: From the dihybrid cross, law of independent assortment can be derived which states that, when two pairs of traits are combined in a hybrid, segregation of one pair of characters is independent of the other pair of characters. Therefore, the specialized computer-based programme was developed. Question 21- Why does the lac operon shut down sometime after the addition of lactose in the medium where E.coli was growing? Free Download CBSE Class 12 Biology Important Questions in PDF format. Choose the correct reasons for Rheumatoid arthritis for the following: More antibodies are produced in the body. b. Rhizobium bacteria present in the root nodules of leguminous plants form a symbiotic association and fixes atmospheric nitrogen into organic forms, which is used by the plant as nutrient. Here we have given NCERT Class 12 Biology Important Questions Chapterwise State Board. Question 37- Observe the diagram and answer: a. We are increasing the use of non-biodegradable products. What is the technique through which Gene expression can be controlled with the help of an RNA molecule? The biodegradable materials can be put into deep pits in the ground and be left for the natural breakdown. Free-living bacteria in the soil Azospirillum and Azotobacter can fix atmospheric nitrogen thus enriching the nitrogen content of the soil. Categories . CBSE has given more weight to the school-based/internal assessment. Some microbes can be extremely beneficial while some others can be fatal enough. b) Name the first transgenic cow developed and state the improvement in the quality of the product produced by it. This is one of the theoretical subjects in the Class 12, loved by many students because of its concepts. Turner’s Syndrome: The affected individual shows the following characters- Females are sterile as ovaries are rudimentary and the lack of other sexual characters. Down’s Syndrome: The cause is the presence of an additional copy of chromosome number 21 (trisomy of 21). It is an asexually reproduced mass of cells, that is capable of developing into a new organism. 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 … b) How lane one is different from lane 2, 3 and 4 in the Gel electrophoresis set up? Top. Section A contains Answer: a. These questions are based on NCERT textbooks and can be expected in the upcoming CBSE Class 12th Biology … Answer: In some species, the diploid egg cell is formed without reduction division and develops into the embryo without fertilization. Question 46- a. Section D contains Question from very important topics are covered by NCERT Exemplar Class 12.. You also get idea about the type of questions and method to answer in your class 12th examination. Answer: As the male partner is suffering from low sperm count, Intracytoplasmic sperm injection technique should be used to directly inject sperm into the ovum. State the Mendelian principle which can be derived from a dihybrid cross and not from monohybrid cross. How will he be benefitted? Check important questions & answers for CBSE Class 12th Biology Board Exam 2020. Answer: Clouds and gases reflect one-fourth of incoming solar radiation/absorb some of it/but almost half of incoming solar radiation falls on Earth’s surface heating it/while a small is reflected backs/Earth’s surface re-emits heat in the form of infrared radiation/but part of this does not escape into space as atmospheric gases absorb a major fraction of it. Microbes can be used to decrease the use of chemical fertilizers. 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. Protein-enriched beans – broad, lablab, French and garden peas. b. a) While cloning vectors, which of the two will be preferred by biotechnologists - bacteriophages or plasmids. We can do our bit by carrying a cloth or other natural fibre carry-bags when we go for shopping and by refusing to take the polythene bags from shopkeepers. 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This triggers the release of oxytocin from the maternal pituitary. b) The given agarose gel electrophoresis shows the migration of undigested DNA fragments in lane 1 and digested set of DNA fragments in lane 2 to 4. c) The separated DNA fragments can be visualized only after staining the DNA with a compound known as ethidium bromide followed by exposure to UV radiation. Those who are going to appear in the upcoming NIOS Board 12th Exam 2020 are advised to download NIOS Previous Year Question Papers with Solutions 2020 for Class 12th to know the exam pattern and difficulty level of exam. Once an insect ingests the inactive toxin, it is converted into an active form. psychological barriers are the acid in the stomach and saliva in the mouth. HSC Board Exams are fast approaching and students are getting anxious about how to prepare for their HSC Board Exams. Describe one example each of chromosomal disorder along with the symptoms involving an autosome and a sex chromosome. 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