Science (English Medium)
Academic Year: 2021-2022
Date & Time: 30th May 2022, 10:30 am
Duration: 2h
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General Instructions :
- This question paper contains 13 questions that are compulsory.
- The question paper has three sections. Sections A, B, and C.
- Section - A has 6 questions of 2 marks each.
- Section - B has 6 questions of 3 marks each
- Section - C has a case-based question of 5 marks.
- There is no overall choice. However, internal choices have been provided in some questions. A student has to attempt only one of the alternatives in such questions.
- Wherever necessary, neat and properly labelled diagrams should be drawn.
Many members of genus Glomus form a mycorrhizal association with plants. Elaborate how is this association beneficial to the plants.
Chapter: [0.08] Microbes in Human Welfare
Can we use slurry of human excreta instead of cowdung slurry to produce biogas in a typical biogas plant? Support your answer giving reasons.
Chapter: [0.08] Microbes in Human Welfare
State the mode of action of cocaine on the human body. Write the scientific name of the source plant it is obtained from.
Chapter: [0.07] Human Health and Diseases
Enumerate four most common warning signs of drug and alcohol abuse amongst the youth.
Chapter: [0.07] Human Health and Diseases
Study the given diagram of the Sewage Treatment Plant (S.T.P.) and answer the question that follows:
- Which one of the two 'S.T.P.' (A) or (B) will be more effective in treating the human excreta in municipal waste?
- Write the steps followed in carrying the treatment of the sewage in step (Z), once the BOD of sewage is reduced significantly till it is passed on to the "anaerobic sludge digesters".
Chapter: [0.08] Microbes in Human Welfare
Write the best method to measure the population density of a single Banyan tree in comparison to Partlzenium weeds in a forest by an ecologist. Explain and justify your answer.
Chapter: [0.11] Organisms and Populations
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What would be the best method to measure the total population density of the number of fishes in river and why?
Chapter: [0.11] Organisms and Populations
Many people experience allergic symptoms of sneezing or wheezing on exposure to certain substances in the environment. Give two examples of such substances. Which type of antibodies are produced by the body in response to these substances? Mention the role of mast cells in this kind of allergic response.
Chapter: [0.07] Human Health and Diseases
Why do doctors have to carry many tests for selecting a person to be a suitable donor for someone who is going for an organ transplant and not take the organ from just any body? Explain giving reason.
Chapter: [0.07] Human Health and Diseases
Name the drug a patient who has undergone a successful organ transplant, has to take all his/her life.
Chapter: [0.08] Microbes in Human Welfare
A cell-free method of amplifying DNA first developed in the mid 1980's revolutionised the field of biotechnology, Name the method and explain the basic steps of the technique involved.
Chapter: [0.1] Biotechnology and Its Application
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Given below is an equation describing the Species-Area relationship between species richness and area for a wide variety of taxa as angiosperm plants, birds, bats etc. S = CAz
- Give a graphical representation of the given equation showing Species-Area relationship.
- What does 'S' represent in the given equation?
- What is the value of 'Z' (regression coefficient) for frugivorous birds and mammals in the tropical forests of different continents?
Chapter: [0.13] Biodiversity and Its Conservation
Given below is a 'pie chart' representing the global biodiversity:
Proportionate number of species of major taxa.
- Identify (X) and (Y) in the given 'pie chart'.
- "Extinction of species across taxa are not random." Which group amongst the vertebrates is more vulnerable to extinction?
- Give one example of each of the recent extinctions of species in Russia, Mauritius and Australia.
Chapter: [0.13] Biodiversity and Its Conservation
Non viral and non vector methods are sometimes used to transfer genes or alien DNA into a plant cell. Explain one such method used in genetic engineering.
Chapter: [0.09] Biotechnology - Principles and Processes
Enlist two criteria that are used to identify a region for maximum protection as 'Biodiversity hotspots'.
Chapter: [0.13] Biodiversity and Its Conservation
Name any two biodiversity hot spots in India.
Chapter: [0.13] Biodiversity and Its Conservation
Cloning of genes, play a very significant role in genetic engineering, helping the transfer of desirable foreign genes into different hosts. The scientists, to make this process easier and effective are creating engineered vectors in such a way that they help easy linking of foreign DNA and selection of recombinants from non-recombinants. 'pBR322' is one such engineered vectors developed by scientists. A diagram of an engineered vector pBR322 is given below:
- Name the host for this cloning vector.
- Identify 'Rop' and 'Ori' in the diagram from 'U', 'V', 'W', 'X', 'Y' and 'Z'. Write their functions.
- Draw the fragments that will be formed by the action of 'Z' (marked in the diagram) on the specific site of the DNA segment given below:
5' --- GTACGAATCCTGA --- 3'
3' --- CATGCTTAGGACT --- 3'
Chapter: [0.09] Biotechnology - Principles and Processes
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RNA interference (RNAi) holds great potential as a therapeutic agent for the treatment of human diseases and as biocontrol agents in controlling pests in the field agriculture. An experiment was carried to study the use of 'RNAi' for the potential treatment of disorders of cholesterol metabolism. Some people possess genetic mutations with elevated levels of ApoB gene which predisposes them to coronary artery diseases. Lowering the amount ApoB can reduce the number of lipoproteins and lower the blood cholesterol. Tracy Zimmerman and her colleagues used RNAi in 2006 to reduce the level of ApoB in non human primates Cynomolgus monkeys. One group of monkeys were given RNAi treatment (small interfering RNAs, SiRNAs) (doses 1 mg/kg, SiRNAs), second group of monkeys were given RNAi treatment (doses 2.5 mg/kg, SiRNAs) and third group of monkeys were injected with saline. |
The results of the study are depicted in the graph below:
- How does the treatment with 2.5 mg/kg bring an effect on cholesterol metabolism when compared from 24 hours and 144 hours?
- Write any two natural sources from where dsRNA molecule could be obtained for silencing the specific mRNA.
- How is RNAi used in controlling the infection on the roots of tobacco plants by the nematode Meloidogyne incognitia?
Chapter: [0.1] Biotechnology and Its Application
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