CBSE Class 12 Biology 2022 question paper (57/3)
Maximum marks 35 · Time 2 hours · 3 sets
Try each question first, then open its model answer. Where the paper offers a choice, both questions are shown with OR between them.
Section A
2 marks each
- Q.12 marksA boy developed some allergic reactions when he straight entered into his air conditioned room after a game of football outside his house. Write any two symptoms that could be noticed in such condition. How does our body combat such conditions ?
- Q.2 (a)2 marks(i) Write the Scientific name of the plant from where natural cannabinoids are obtained. (ii) Mention the parts of the plant that are used for extracting the drug. (iii) How does the drug affect human body ?
OR
Q.2 (b)2 marksEpithelial lining of our intestine is considered as secondary lymphoid organ. Justify the statement.- Q.32 marksFarmers are often suggested to use the following organisms in their crop land so as to improve the soil fertility. (i) Rhizobium (ii) Anabaena Explain.
- Q.42 marksOrganic farmer use Trichoderma and Baculovirus as biological control agents. Explain.
- Q.52 marksMammals are capable of maintaining homeostasis. But, very few smaller animals can survive in polar regions. Give reasons.
- Q.6 (a)2 marksObserve the schematic representation given above and answer the following questions : (i) Identify A and B. (ii) Calculate the growth rate of bacteria in a curd sample, where 1 million bacteria increased to two million, within a period of one hour.
OR
Q.6 (b)2 marksIdentify the type of pyramid given above. Write the identifying feature on the basis of which you identified it.
Section B
3 marks each
- Q.73 marks(a) Write the complete name of the diagnostic test for AIDS. Explain the principle it works on. (b) Name the type of genetic material present in AIDS causing pathogen.
- Q.83 marksA patient complains of suffering from constipation, stomach ache, stool with blood clots and excess mucous. The physician diagnosed it as amoebiasis, after stool test. (a) Write the scientific name of the microbe identified in the stool sample. (b) How do you think, the patient must have contracted it ? (c) Write your suggestions to the patient to avoid infection in future.
- Q.93 marksWhat are cry-proteins ? With the help of a suitable example, explain how it acts as a biological pesticide.
- Q.103 marks(a) Write the inference drawn by Alexander von Humboldt after his extensive explorations of South Americal jungle. (b) Study the graph given below : As per Alexander von Humboldt, what do the symbols S, A, Z and C in the graph stand for, in respect of a species and area relationship ?
- Q.11 (a)3 marksExplain the concept of "co-extinction" by taking two examples.
OR
Q.11 (b)3 marks"Forests provide intangible benefits to us." Explain by taking three different areas, how.- Q.123 marks(a) Given below is the stepwise schematic representation of the process of electrophoresis. Identify the 'alphabets' representing (i) Anode end (ii) smallest/lightest DNA strand in the matrix (iii) Agarose gel (b) What is elution ? State the importance of elution in this process.
Section C
- Enzyme Taq polymerase, is extracted from a eubacterial microorganism Thermus aquaticus from Yellowstone National Park in Montana, USA and isolated by Chien et al. (1976). Taq polymerase successfully replaced the DNA polymerase from E.coli that was being used in PCR earlier and this shift revolutionised the PCR technique.Q.13 (a) (i)2 marksTaq polymerase after its discovery replaced E.coli DNA polymerase in PCR technique. Explain giving reasons why was the need felt for the change ?
- Q.13 (a) (ii)2 marksWhat is a primer and its importance in PCR ?
- Q.13 (a) (iii)1 markWrite the importance of PCR as a diagnostic tool.
OR
Biotechnology revolves around the "gene of interest", with an objective to open various avenues for human welfare in health, medicine, pharma, agriculture etc. using different techniques, tools and processes. One of the breakthroughs of biotechnology in medicine is the gene therapy.Q.13 (b)5 marks(i) Name the human disease for which the gene therapy was used for the first time. (ii) Explain the steps of gene therapy carried to cure the disease using the lymphocytes of the patient. Why is this therapy not a permanent cure of the disease ? (iii) Write the possible permanent cure of the disease by the gene therapy that is in progress.
Section A
2 marks each
- Q.1 (a)2 marksObserve the schematic representation given above and answer the following questions : (i) Identify A and B. (ii) Calculate the growth rate of bacteria in a curd sample, where 1 million bacteria increased to two million, within a period of one hour.
OR
Q.1 (b)2 marksIdentify the type of pyramid given above. Write the identifying feature on the basis of which you identified it.- Q.22 marksA boy developed some allergic reactions when he straight entered into his air conditioned room after a game of football outside his house. Write any two symptoms that could be noticed in such condition. How does our body combat such conditions ?
- Q.3 (a)2 marks(i) Write the Scientific name of the plant from where natural cannabinoids are obtained. (ii) Mention the parts of the plant that are used for extracting the drug. (iii) How does the drug affect human body ?
OR
Q.3 (b)2 marksEpithelial lining of our intestine is considered as secondary lymphoid organ. Justify the statement.- Q.42 marksWhat are flocs ? State their role in biological treatment of sewage.
- Q.52 marksHow are 'in-situ' and 'ex-situ' approaches of biodiversity conservations different from each other ?
- Q.62 marksFarmers are often suggested to use the following organisms in their crop land so as to improve the soil fertility. (i) Rhizobium (ii) Anabaena Explain.
Section B
3 marks each
- Q.73 marksRestriction endonucleases are used in genetic engineering to form recombinant DNA. Explain only with the help of a flow chart the steps carried in the formation of a recombinant DNA.
- Q.83 marks(a) Write the inference drawn by Alexander von Humboldt after his extensive explorations of South Americal jungle. (b) Study the graph given below : As per Alexander von Humboldt, what do the symbols S, A, Z and C in the graph stand for, in respect of a species and area relationship ?
- Q.93 marks(a) Given below is the stepwise schematic representation of the process of electrophoresis. Identify the 'alphabets' representing (i) Anode end (ii) smallest/lightest DNA strand in the matrix (iii) Agarose gel (b) What is elution ? State the importance of elution in this process.
- Q.103 marks(a) Explain the property of contact inhibition and its effect on normal human cells and cancerous cells. (b) Why are biological modifiers like -interferon required for cancer treatment ? How do they act to treat the disease ?
- Q.113 marksWhat are cry-proteins ? With the help of a suitable example, explain how it acts as a biological pesticide.
- Q.12 (a)3 marksExplain the concept of "co-extinction" by taking two examples.
OR
Q.12 (b)3 marks"Forests provide intangible benefits to us." Explain by taking three different areas, how.
Section C
- Enzyme Taq polymerase, is extracted from a eubacterial microorganism Thermus aquaticus from Yellowstone National Park in Montana, USA and isolated by Chien et al. (1976). Taq polymerase successfully replaced the DNA polymerase from E.coli that was being used in PCR earlier and this shift revolutionised the PCR technique.Q.13 (a) (i)2 marksTaq polymerase after its discovery replaced E.coli DNA polymerase in PCR technique. Explain giving reasons why was the need felt for the change ?
- Q.13 (a) (ii)2 marksWhat is a primer and its importance in PCR ?
- Q.13 (a) (iii)1 markWrite the importance of PCR as a diagnostic tool.
OR
Biotechnology revolves around the "gene of interest", with an objective to open various avenues for human welfare in health, medicine, pharma, agriculture etc. using different techniques, tools and processes. One of the breakthroughs of biotechnology in medicine is the gene therapy.Q.13 (b)5 marks(i) Name the human disease for which the gene therapy was used for the first time. (ii) Explain the steps of gene therapy carried to cure the disease using the lymphocytes of the patient. Why is this therapy not a permanent cure of the disease ? (iii) Write the possible permanent cure of the disease by the gene therapy that is in progress.
Section A
2 marks each
- Q.12 marksName the diseases and their mode of transmission in human by (i) common round worm and (ii) filarial worm.
- Q.2 (a)2 marks(i) Write the Scientific name of the plant from where natural cannabinoids are obtained. (ii) Mention the parts of the plant that are used for extracting the drug. (iii) How does the drug affect human body ?
OR
Q.2 (b)2 marksEpithelial lining of our intestine is considered as secondary lymphoid organ. Justify the statement.- Q.32 marksA boy developed some allergic reactions when he straight entered into his air conditioned room after a game of football outside his house. Write any two symptoms that could be noticed in such condition. How does our body combat such conditions ?
- Q.42 marksFarmers are often suggested to use the following organisms in their crop land so as to improve the soil fertility. (i) Rhizobium (ii) Anabaena Explain.
- Q.5 (a)2 marksObserve the schematic representation given above and answer the following questions : (i) Identify A and B. (ii) Calculate the growth rate of bacteria in a curd sample, where 1 million bacteria increased to two million, within a period of one hour.
OR
Q.5 (b)2 marksIdentify the type of pyramid given above. Write the identifying feature on the basis of which you identified it.- Q.62 marksExplain the role of 'B' and 'T' lymphocytes in providing immunity to humans.
Section B
3 marks each
- Q.73 marksPlasmodium enters the human body through the bite of infected female Anopheles. Trace its life cycle till the onset of malaria in human.
- Q.83 marks(a) Write the complete name of the diagnostic test for AIDS. Explain the principle it works on. (b) Name the type of genetic material present in AIDS causing pathogen.
- Q.93 marks(a) Given below is the stepwise schematic representation of the process of electrophoresis. Identify the 'alphabets' representing (i) Anode end (ii) smallest/lightest DNA strand in the matrix (iii) Agarose gel (b) What is elution ? State the importance of elution in this process.
- Q.10 (a)3 marksExplain the concept of "co-extinction" by taking two examples.
OR
Q.10 (b)3 marks"Forests provide intangible benefits to us." Explain by taking three different areas, how.- Q.113 marksWhat are cry-proteins ? With the help of a suitable example, explain how it acts as a biological pesticide.
- Q.123 marks(a) "For ethical reasons, biodiversity must be conserved." Do you agree ? Write your views in support of your answer. (b) Write the characteristic features of a specific area on the basis of which it is designated as a "hot spot". Write any one major threat to these areas.
Section C
- Enzyme Taq polymerase, is extracted from a eubacterial microorganism Thermus aquaticus from Yellowstone National Park in Montana, USA and isolated by Chien et al. (1976). Taq polymerase successfully replaced the DNA polymerase from E.coli that was being used in PCR earlier and this shift revolutionised the PCR technique.Q.13 (a) (i)2 marksTaq polymerase after its discovery replaced E.coli DNA polymerase in PCR technique. Explain giving reasons why was the need felt for the change ?
- Q.13 (a) (ii)2 marksWhat is a primer and its importance in PCR ?
- Q.13 (a) (iii)1 markWrite the importance of PCR as a diagnostic tool.
OR
Biotechnology revolves around the "gene of interest", with an objective to open various avenues for human welfare in health, medicine, pharma, agriculture etc. using different techniques, tools and processes. One of the breakthroughs of biotechnology in medicine is the gene therapy.Q.13 (b)5 marks(i) Name the human disease for which the gene therapy was used for the first time. (ii) Explain the steps of gene therapy carried to cure the disease using the lymphocytes of the patient. Why is this therapy not a permanent cure of the disease ? (iii) Write the possible permanent cure of the disease by the gene therapy that is in progress.