Science (English Medium)
Academic Year: 2018-2019
Date: March 2019
Duration: 2h
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- Section A contains question numbers 1 to 5, very short answer type questions of one mark each.
- Section B contains question number 6 to 12, short answer type-I questions of two marks each.
- Section C contains question number 13 to 24, short answer type-II questions of three marks each.
- Section D contains question number 25 to 27, long answer type questions of five marks each.
Answer the following question.
British geneticist R.C. Punnett developed a graphical representation of a genetic cross called “Punnett Square”. Mention the possible result this representation predicts of the genetic cross carried.
Chapter: [0.04] Principles of Inheritance and Variation
Answer the following question.
State the two principal outcomes of the experiments conducted by Louis Pasteur on the origin of life.
Chapter: [0.06] Evolution
Answer the following question.
Name the layer of the atmosphere that is associated with ‘good ozone’.
Chapter: [0.04] Environmental Issues
Answer the following question.
Mention the term used to describe a population interaction between an orchid growing on a forest tree.
Chapter: [0.11] Organisms and Populations
Answer the following question.
What are ‘flocs’, formed during secondary treatment of sewage?
Chapter: [0.08] Microbes in Human Welfare
Answer the following question.
Write any two places where methanogens can be found.
Chapter: [0.08] Microbes in Human Welfare
Answer the following question.
At what stage does the meiosis occur in an organism exhibiting a haploidic life cycle and mention the fate of the products thus produced?
Chapter: [0.01] Reproduction in Organisms
Answer the following question.
You are conducting artificial hybridization on papaya and potato. Which one of them would require the step of emasculation and why? However, for both, you will use the process of bagging. Justify giving one reason.
Chapter: [0.01] Sexual Reproduction in Flowering Plants
How would the gene flow or genetic drift affect the population in which either of them happens to take place?
Chapter: [0.06] Evolution
Answer the following question.
Differentiate between the roles of B-lymphocytes and T-lymphocytes in generating immune responses.
Chapter: [0.07] Human Health and Diseases
Answer the following question:
The principle of vaccination is based on the property of the "memory" of the immune system. Taking one suitable example, justify the statement.
Chapter: [0.07] Human Health and Diseases
Answer the following question.
Explain the relevance of "Totipotency" and "Somaclones" in raising healthy banana plants from virus-infected banana plants.
Chapter: [0.08] Strategies for Enhancement in Food Production
Answer the following question.
How is a continuous culture system maintained in bioreactors and why?
Chapter: [0.1] Biotechnology and Its Application
Answer the following question.
List any four ways by which GMOs have been useful for enhanced crop output.
Chapter: [0.1] Biotechnology and Its Application
Answer the following question.
Mention four significant services that a healthy forest ecosystem provides.
Chapter: [0.12] Ecosystem
Answer the following question:
Substantiate with the help of one example that in an ecosystem mutualists
(i) tend to co-evolve and
(ii) are also one of the major causes of biodiversity loss.
Chapter: [0.13] Biodiversity and Its Conservation
Answer the following question.
Pollen banks are playing a very important role in promoting plant breeding programs the world over. How are pollens preserved in the pollen banks? Explain. How are such banks benefitting our farmers? Write any two ways.
Chapter: [0.01] Sexual Reproduction in Flowering Plants
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Draw a label diagram.
Draw a labeled diagram to show the interrelationship of four accessory ducts in a human male reproductive system.
Chapter: [0.02] Human Reproduction
Draw a label diagram.
Draw a sectional view of the human ovary showing the different stages of developing follicles, corpus luteum, and ovulation.
Chapter: [0.02] Human Reproduction
Answer the following question.
Compare in any three ways the chromosomal theory of inheritance as proposed by Sutton and Bovery with that of experimental results on pea plant presented by Mendel.
Chapter: [0.04] Principles of Inheritance and Variation
Answer the following question.
Explain linkage and recombination as put forth by T.H. Morgan based on his observations with the Drosophila melanogaster crossing experiment.
Chapter: [0.04] Principles of Inheritance and Variation
Answer the following question.
Write the basis on which Alfred Sturtevant explained gene mapping.
Chapter: [0.04] Principles of Inheritance and Variation
Answer the following question.
Explain the mechanism of DNA replication with the help of a replication fork. What role does the enzyme ONA-ligase play in a DNA replication fork?
Chapter: [0.05] Molecular Basis of Inheritance
Answer the following question.
Construct and label a transcription unit from which the RNA segment given below has been transcribed. Write the complete name of the enzyme that transcribed this RNA.
Chapter: [0.05] Molecular Basis of Inheritance
Answer the following question.
Write two differences between Homo erectus and Homo habilis.
Chapter: [0.06] Evolution
Rearrange the following from early to late geologic periods:
Carboniferous, Silurian, Jurassic.
Chapter: [0.06] Evolution
Answer the following question:
Name the group of bacteria involved in setting milk into curd. Explain the process they carry in doing so. Write another beneficial role of such bacteria.
Chapter: [0.08] Microbes in Human Welfare
Answer the following question:
Beekeeping practice is a good income generating industry. Write the different points to be kept in mind for successful beekeeping. Write the scientific name of the most common Indian species used for the purpose.
Chapter: [0.08] Strategies for Enhancement in Food Production
Match the microbes listed under Column-A with the products mentioned under Column-B.
| Column -A | Column -B | ||
| (H) | Peniciffium notatum | (i) | Statin |
| (I) | Trichoderma polysporum | (ii) | ethanol |
| (J) | Monascus purpures | (iii) | antibiotic |
| (K) | Saccharomyces cerevisia | (iv) | Cyclosporin-A |
Chapter: [0.08] Microbes in Human Welfare [0.08] Microbes in Human Welfare
Answer the following question:
Why does 'Swiss Cheese' develop large holes?
Chapter: [0.08] Microbes in Human Welfare
Answer the following question:
Describe the formation of recombinant DNA by the action of EcoRI.
Chapter: [0.09] Biotechnology - Principles and Processes
Answer the following question:
Describe the process of amplification of the "gene of interest" using the PCR technique.
Chapter: [0.09] Biotechnology - Principles and Processes
Answer the following question.
Two children, A and B aged 4 and 5 years respectively visited a hospital with a similar genetic disorder. The girl A was provided enzyme-replacement therapy and was advised to revisit periodically for further treatment. The girl, B was, however, given a therapy that did not require revisit for further treatment.
Name the ailments the two girls were suffering from?
Chapter: [0.04] Principles of Inheritance and Variation
Answer the following question.
Two children, A and B aged 4 and 5 years respectively visited a hospital with a similar genetic disorder. The girl A was provided enzyme-replacement therapy and was advised to revisit periodically for further treatment. The girl, B was, however, given a therapy that did not require revisit for further treatment.
Why did the treatment provided to girl A required repeated visits?
Chapter: [0.04] Principles of Inheritance and Variation
Answer the following question.
Two children, A and B aged 4 and 5 years respectively visited a hospital with a similar genetic disorder. The girl A was provided enzyme-replacement therapy and was advised to revisit periodically for further treatment. The girl, B was, however, given a therapy that did not require revisit for further treatment.
How was the girl B cured permanently?
Chapter: [0.04] Principles of Inheritance and Variation
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List six advantages of the "ex-situ' approach to conservation of biodiversity.
Chapter: [0.13] Biodiversity and Its Conservation
Answer the following question:
While on a visit to a pond in the city-neighborhood, the visitors were delighted to find a large expanse of water covered with colorful algal mass.
As a student of biology, do you agree with their delight? Give reasons in support of your answer.
Chapter: [0.04] Environmental Issues
Answer the following question:
While on a visit to a pond in the city-neighborhood, the visitors were delighted to find a large expanse of water covered with colorful algal mass.
Explain the cause of such algal growth.
Chapter: [0.04] Environmental Issues
Explain one application of the following:
Amniocentesis
Chapter: [0.03] Reproductive Health [0.03] Reproductive Health [0.03] Reproductive Health
Explain one application of the following:
Lactational amenorrhea
Chapter: [0.03] Reproductive Health
Explain one application of the following:
ZIFT
Chapter: [0.03] Reproductive Health
Prepare a poster for the school program depicting the objectives of:
"Reproductive and Child Health Care Programme".
Chapter: [0.03] Reproductive Health [0.03] Reproductive Health [0.03] Reproductive Health
Answer the following question.
Explain any two ways by which apomictic seed can develop.
Chapter: [0.01] Sexual Reproduction in Flowering Plants
Answer the following question.
List one advantage and one disadvantage of an apomictic crop.
Chapter: [0.1] Biotechnology and Its Application
Answer the following question:
Why do farmers find the production of hybrid seeds costly?
Chapter: [0.1] Biotechnology and Its Application
Answer the following question.
Differentiate between incomplete dominance and co-dominance. Substantiate your answer with one example of each.
Chapter: [0.04] Principles of Inheritance and Variation [0.04] Principles of Inheritance and Variation
Write the contributions of the following scientists in deciphering the genetic code.
George Gamow; Hargobind Khorana; Marshall Nirenberg; Severo Ochoa
Chapter: [0.05] Molecular Basis of Inheritance [0.05] Molecular Basis of Inheritance [0.05] Molecular Basis of Inheritance
Answer the following question.
State the importance of a Genetic code in protein biosynthesis.
Chapter: [0.05] Molecular Basis of Inheritance [0.05] Molecular Basis of Inheritance [0.05] Molecular Basis of Inheritance
Answer the following question.
What is "population" according to you as a biology student?
Chapter: [0.11] Organisms and Populations
Answer the following question.
"The size of a population for any species is not a static parameter." Justify the statement with specific reference to fluctuations in the population density of a region in a given period of time.
Chapter: [0.11] Organisms and Populations
Answer the following question.
What is hydrarch succession?
Chapter: [0.12] Ecosystem
Answer the following question.
Compare the pioneer species and climax communities of hydrarch and xerarch succession respectively.
Chapter: [0.12] Ecosystem
Answer the following question.
List the factors upon which the type of invading pioneer species depends on secondary hydrarch succession. Why is the rate of this succession faster than that of primary succession?
Chapter: [0.12] Ecosystem
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