SAMPLE QUESTION PAPER (2021-22)
BIOLOGY (044)
TERM II
CLASS 12
Time: 2 Hrs Max. Marks: 40
GENERAL INSTRUCTIONS
i. All questions are compulsory.
ii. The question paper has three sections and 13 questions. All questions are compulsory.
iii. Mark distribution:
a. Section–A has 6 questions of 2 marks each
b. Section–B has 6 questions of 3 marks each
c. Section–C has a case-based question of 5 marks.
iv. 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.
v. Wherever necessary, neat and properly labelled diagrams should be drawn.
SECTION A
Attempt all questions: –
Q.1 Some diseases require an intermediate host which often acts as a vector of a parasite to reach its definitive host, where it will become mature. One such host is Aedes mosquito. Name two diseases which can be controlled by the eradication of this mosquito.
Q.2. How is designation of certain areas as hotspots a step towards biodiversity conservation? Name any two hotspots in India.
OR
Identify the areas labelled I, II, III and IV in the pie chart given below representing the biodiversity of plants showing their proportionate number of species of major taxa.
Q.3. Out of the given three age pyramids, which pyramid reflects the growth status of human population? Explain.
Q.4. Identify the plant shown in the figure below and mention the useful as well as the harmful drug obtained from it.
OR
During winter, pneumonia and common cold are very prevalent. But these two diseases are different from each other in etiology. Write down one such difference between them.
Q.5. Organic farmers prefer biological control of disease and pests to the use of chemicals for the same purpose. Justify.
Q.6. A disease is a disorder that affects the health by affecting an organism’s body, organs, tissues or cells. These are grouped into communicable and non-communicable diseases. Give differences between them with example
SECTION B
Q.7. In a habitat with unlimited resources, which type of population growth can be observed? Support your answer with a graphical representation.
Q.8. Why DNA cannot pass through the cell membrane? Explain a method by which bacterial cell made competent to take up recombinant DNA from the medium.
Q. 9. Name the source organism of the gene cry IAc and its target pest. Why do the toxic insecticidal proteins only kill the insect and not the bacteria itself?
Q.10 (a) Since the origin of life on earth, there were five episodes of mass extinction o species. How is the ‘sixth extinction’ presently in progress, different from the previous episodes?
(b) There can be various factors responsible for ‘sixth extinction’. Write down the main factor.
(c) List any four points that can help to overcome this disaster.
Q.11 (a) The image shown below is of an anaerobic sludge digester. Explain in what way, it is important in sewage treatment.
(b) What would happen if a large volume of untreated sewage is discharged into a river?
OR
It is generally observed that the children who had suffered from chickenpox in their childhood may not contract the same disease in their adulthood. Explain giving reasons the basis of such an immunity in an individual. Name this kind of immunity.
Q.12 The image depict the fungal hyphae of members of the genus-Glomus.
(a) Name the type of association that this fungi exhibit with higher plants.
(b) How does the application of this fungal-Glomus to the agricultural farm increase the farm output?
SECTION C
Q.13 The image below depicts a recombinant technology product made by American Eli Lilly company in 1983. It is one of the examples of use of recombinant therapeutics for humans. This is famous as it does not induce any unwanted immunological response as in case of similar products isolated from non-humans sources.
(a) Name the source from which it was extracted earlier. Why is this no more in use by diabetic people?
(b) Explain the process of its synthesis by Eli Lilly company. Name the technique used by the company.
(c) How is this recombinant therapeutic produced by Eli Lilly different from the one produced by non-human sources?
OR
In recombinant technology, the desired genes for administration is/are selected, followed by selecting a perfect vector into which the desired gene is to be integrated and rDNA formed.
These recombinant cells are then multiplied in large vessels called bioreactor, under optimum conditions for growth of the product.
(a) What are all the optimum conditions provided by bioreactor?
(b) What happens in a continuous culture system?
(c) Name the components of a bioreactor and also write names of two types of bioreactor?