CBSE Biology All India Past year paper - 2018, Class 12 | Additional Study Material for NEET PDF Download

 Page 1


  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
CBSE 
 Class XII Biology (Theory) 
Board Paper 2018 All India (Set 3) 
 
Time allowed: 3 hrs Maximum Marks: 70 
 
General Instructions: 
1. There are total 26 questions and five sections in the question paper. 
All questions are compulsory. 
2. Section A contains questions number 1 to 5; very short answer type questions of 
1 mark each. 
3. Section B contains questions number 6 to 10, short-answer type I questions of 2 
marks each. 
4. Section C contains questions number 11 to 22, short answer type II questions of 
3 marks each. 
5. Section D contains question number 23, value based question of 4 marks. 
6. Section E contains questions number 24 to 26, long-answer type questions of 5 
marks each. 
7. There is no overall choice in the question paper; however, an internal choice is 
provided in one question of 2 marks, one question of 3 marks and all the three 
questions of 5 marks. In these questions, an examinee is to attempt any of the 
two given alternatives. 
 
SECTION A 
 
1. How do cytokine barriers provide innate immunity in humans? [1] 
 
2. Write the dual purpose served by deoxyribonucleoside triphosphates in 
polymerisation. [1] 
 
3. Write the names of the following : [1] 
(a) A 15 mya primate that was ape-like 
(b) A 2 mya primate that lived in East African grasslands 
 
4. Mention the chemical change that proinsulin undergoes, to be able to act as 
mature insulin. [1] 
 
5. Name two diseases whose spread can be controlled by the eradication of Aedes 
mosquitoes. [1] 
 
  
Page 2


  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
CBSE 
 Class XII Biology (Theory) 
Board Paper 2018 All India (Set 3) 
 
Time allowed: 3 hrs Maximum Marks: 70 
 
General Instructions: 
1. There are total 26 questions and five sections in the question paper. 
All questions are compulsory. 
2. Section A contains questions number 1 to 5; very short answer type questions of 
1 mark each. 
3. Section B contains questions number 6 to 10, short-answer type I questions of 2 
marks each. 
4. Section C contains questions number 11 to 22, short answer type II questions of 
3 marks each. 
5. Section D contains question number 23, value based question of 4 marks. 
6. Section E contains questions number 24 to 26, long-answer type questions of 5 
marks each. 
7. There is no overall choice in the question paper; however, an internal choice is 
provided in one question of 2 marks, one question of 3 marks and all the three 
questions of 5 marks. In these questions, an examinee is to attempt any of the 
two given alternatives. 
 
SECTION A 
 
1. How do cytokine barriers provide innate immunity in humans? [1] 
 
2. Write the dual purpose served by deoxyribonucleoside triphosphates in 
polymerisation. [1] 
 
3. Write the names of the following : [1] 
(a) A 15 mya primate that was ape-like 
(b) A 2 mya primate that lived in East African grasslands 
 
4. Mention the chemical change that proinsulin undergoes, to be able to act as 
mature insulin. [1] 
 
5. Name two diseases whose spread can be controlled by the eradication of Aedes 
mosquitoes. [1] 
 
  
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
SECTION B 
6. How did a citizen group called Friends of Arcata Marsh, Arcata, California, USA, 
help to improve water quality of the marshland using Integrated Waste Water 
Treatment? Explain in four steps. [2] 
 
7. Your advice is sought to improve the nitrogen content of the soil to be used for 
cultivation of a non-leguminous terrestrial crop. [2] 
(a) Recommend two microbes that can enrich the soil with nitrogen.  
(b) Why do leguminous crops not require such enrichment of the soil? 
 
8. You have obtained a high yielding variety of tomato. Name and explain the 
procedure that ensures retention of the desired characteristics repeatedly in 
large populations of future generations of the tomato crop. [2] 
 
9.   
(a) Name the source plant of heroin drug. How is it obtained from the plant? 
(b) Write the effects of heroin on the human body. [2] 
 
10. With the help of an algebraic equation, how did Hardy-Weinberg explain that in 
a given population the frequency of occurrence of alleles of a gene is supposed 
to remain the same through generations? [2] 
OR 
Although a prokaryotic cell has no defined nucleus, yet DNA is not scattered 
throughout the cell. Explain. 
 
  
Page 3


  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
CBSE 
 Class XII Biology (Theory) 
Board Paper 2018 All India (Set 3) 
 
Time allowed: 3 hrs Maximum Marks: 70 
 
General Instructions: 
1. There are total 26 questions and five sections in the question paper. 
All questions are compulsory. 
2. Section A contains questions number 1 to 5; very short answer type questions of 
1 mark each. 
3. Section B contains questions number 6 to 10, short-answer type I questions of 2 
marks each. 
4. Section C contains questions number 11 to 22, short answer type II questions of 
3 marks each. 
5. Section D contains question number 23, value based question of 4 marks. 
6. Section E contains questions number 24 to 26, long-answer type questions of 5 
marks each. 
7. There is no overall choice in the question paper; however, an internal choice is 
provided in one question of 2 marks, one question of 3 marks and all the three 
questions of 5 marks. In these questions, an examinee is to attempt any of the 
two given alternatives. 
 
SECTION A 
 
1. How do cytokine barriers provide innate immunity in humans? [1] 
 
2. Write the dual purpose served by deoxyribonucleoside triphosphates in 
polymerisation. [1] 
 
3. Write the names of the following : [1] 
(a) A 15 mya primate that was ape-like 
(b) A 2 mya primate that lived in East African grasslands 
 
4. Mention the chemical change that proinsulin undergoes, to be able to act as 
mature insulin. [1] 
 
5. Name two diseases whose spread can be controlled by the eradication of Aedes 
mosquitoes. [1] 
 
  
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
SECTION B 
6. How did a citizen group called Friends of Arcata Marsh, Arcata, California, USA, 
help to improve water quality of the marshland using Integrated Waste Water 
Treatment? Explain in four steps. [2] 
 
7. Your advice is sought to improve the nitrogen content of the soil to be used for 
cultivation of a non-leguminous terrestrial crop. [2] 
(a) Recommend two microbes that can enrich the soil with nitrogen.  
(b) Why do leguminous crops not require such enrichment of the soil? 
 
8. You have obtained a high yielding variety of tomato. Name and explain the 
procedure that ensures retention of the desired characteristics repeatedly in 
large populations of future generations of the tomato crop. [2] 
 
9.   
(a) Name the source plant of heroin drug. How is it obtained from the plant? 
(b) Write the effects of heroin on the human body. [2] 
 
10. With the help of an algebraic equation, how did Hardy-Weinberg explain that in 
a given population the frequency of occurrence of alleles of a gene is supposed 
to remain the same through generations? [2] 
OR 
Although a prokaryotic cell has no defined nucleus, yet DNA is not scattered 
throughout the cell. Explain. 
 
  
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
SECTION C 
11.  
(a) Differentiate between analogous and homologous structures.  
(b) Select and write analogous structures from the list given below: [3] 
(i) Wings of butterfly and birds. 
(ii) Vertebrate heads 
(iii) Tendrils of bougainvillea and cucurbita 
(iv) Tubers of sweet potato and potato 
 
12. How has the use of Agrobacterium as vectors helped in controlling Meloidegyne 
incognitia infestation in tobacco plants? Explain in correct sequence. [3] 
 
13.  
(a) “India has greater ecosystem diversity than Norway”. Do you agree with the 
statement? Give reasons in support of your answer. 
(b) Write the difference between genetic biodiversity and species biodiversity 
that exists at all the levels of biological organization. [3] 
OR 
Explain the effect on the characteristics of a river when urban sewage is 
discharged into it. [3] 
14. Explain the mechanism of ‘sex determination’ in birds. How does it differ from 
that of human beings? [3] 
 
15. Explain out-breeding, out-crossing and cross-breeding practices in animal 
husbandry. [3] 
 
16.   
(a) Organic farmers prefer biological control of diseases and pests to the use of 
chemicals for the same purpose. Justify. 
(b) Give an example of a bacterium, a fungus and an insect that are used as 
biocontrol agents. [3] 
 
17.  
(a) How has the development of bioreactor helped biotechnology? 
(b) Name the most commonly used bioreactor and describe its working. [3] 
 
18. Explain the roles of the following with the help of an example each in 
recombinant DNA technology: [3] 
(a) Restriction Enzymes  
(b) Plasmids 
 
19. Differentiate between parthenocarpy and parthenogenesis. Give one example 
of each. [3] 
 
Page 4


  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
CBSE 
 Class XII Biology (Theory) 
Board Paper 2018 All India (Set 3) 
 
Time allowed: 3 hrs Maximum Marks: 70 
 
General Instructions: 
1. There are total 26 questions and five sections in the question paper. 
All questions are compulsory. 
2. Section A contains questions number 1 to 5; very short answer type questions of 
1 mark each. 
3. Section B contains questions number 6 to 10, short-answer type I questions of 2 
marks each. 
4. Section C contains questions number 11 to 22, short answer type II questions of 
3 marks each. 
5. Section D contains question number 23, value based question of 4 marks. 
6. Section E contains questions number 24 to 26, long-answer type questions of 5 
marks each. 
7. There is no overall choice in the question paper; however, an internal choice is 
provided in one question of 2 marks, one question of 3 marks and all the three 
questions of 5 marks. In these questions, an examinee is to attempt any of the 
two given alternatives. 
 
SECTION A 
 
1. How do cytokine barriers provide innate immunity in humans? [1] 
 
2. Write the dual purpose served by deoxyribonucleoside triphosphates in 
polymerisation. [1] 
 
3. Write the names of the following : [1] 
(a) A 15 mya primate that was ape-like 
(b) A 2 mya primate that lived in East African grasslands 
 
4. Mention the chemical change that proinsulin undergoes, to be able to act as 
mature insulin. [1] 
 
5. Name two diseases whose spread can be controlled by the eradication of Aedes 
mosquitoes. [1] 
 
  
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
SECTION B 
6. How did a citizen group called Friends of Arcata Marsh, Arcata, California, USA, 
help to improve water quality of the marshland using Integrated Waste Water 
Treatment? Explain in four steps. [2] 
 
7. Your advice is sought to improve the nitrogen content of the soil to be used for 
cultivation of a non-leguminous terrestrial crop. [2] 
(a) Recommend two microbes that can enrich the soil with nitrogen.  
(b) Why do leguminous crops not require such enrichment of the soil? 
 
8. You have obtained a high yielding variety of tomato. Name and explain the 
procedure that ensures retention of the desired characteristics repeatedly in 
large populations of future generations of the tomato crop. [2] 
 
9.   
(a) Name the source plant of heroin drug. How is it obtained from the plant? 
(b) Write the effects of heroin on the human body. [2] 
 
10. With the help of an algebraic equation, how did Hardy-Weinberg explain that in 
a given population the frequency of occurrence of alleles of a gene is supposed 
to remain the same through generations? [2] 
OR 
Although a prokaryotic cell has no defined nucleus, yet DNA is not scattered 
throughout the cell. Explain. 
 
  
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
SECTION C 
11.  
(a) Differentiate between analogous and homologous structures.  
(b) Select and write analogous structures from the list given below: [3] 
(i) Wings of butterfly and birds. 
(ii) Vertebrate heads 
(iii) Tendrils of bougainvillea and cucurbita 
(iv) Tubers of sweet potato and potato 
 
12. How has the use of Agrobacterium as vectors helped in controlling Meloidegyne 
incognitia infestation in tobacco plants? Explain in correct sequence. [3] 
 
13.  
(a) “India has greater ecosystem diversity than Norway”. Do you agree with the 
statement? Give reasons in support of your answer. 
(b) Write the difference between genetic biodiversity and species biodiversity 
that exists at all the levels of biological organization. [3] 
OR 
Explain the effect on the characteristics of a river when urban sewage is 
discharged into it. [3] 
14. Explain the mechanism of ‘sex determination’ in birds. How does it differ from 
that of human beings? [3] 
 
15. Explain out-breeding, out-crossing and cross-breeding practices in animal 
husbandry. [3] 
 
16.   
(a) Organic farmers prefer biological control of diseases and pests to the use of 
chemicals for the same purpose. Justify. 
(b) Give an example of a bacterium, a fungus and an insect that are used as 
biocontrol agents. [3] 
 
17.  
(a) How has the development of bioreactor helped biotechnology? 
(b) Name the most commonly used bioreactor and describe its working. [3] 
 
18. Explain the roles of the following with the help of an example each in 
recombinant DNA technology: [3] 
(a) Restriction Enzymes  
(b) Plasmids 
 
19. Differentiate between parthenocarpy and parthenogenesis. Give one example 
of each. [3] 
 
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
20. Medically it is advised to all young mothers that breastfeeding is the best for 
their newborn babies. Do you agree? Give reasons in support of your answer.[3] 
 
21. Draw a diagram of a mature human sperm. Label any three parts and write 
their functions. [3] 
 
22.  
(a) Expand VNTR and describe its role in DNA fingerprinting 
(b) List any two applications of DNA fingerprinting technique. [3] 
 
  
Page 5


  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
CBSE 
 Class XII Biology (Theory) 
Board Paper 2018 All India (Set 3) 
 
Time allowed: 3 hrs Maximum Marks: 70 
 
General Instructions: 
1. There are total 26 questions and five sections in the question paper. 
All questions are compulsory. 
2. Section A contains questions number 1 to 5; very short answer type questions of 
1 mark each. 
3. Section B contains questions number 6 to 10, short-answer type I questions of 2 
marks each. 
4. Section C contains questions number 11 to 22, short answer type II questions of 
3 marks each. 
5. Section D contains question number 23, value based question of 4 marks. 
6. Section E contains questions number 24 to 26, long-answer type questions of 5 
marks each. 
7. There is no overall choice in the question paper; however, an internal choice is 
provided in one question of 2 marks, one question of 3 marks and all the three 
questions of 5 marks. In these questions, an examinee is to attempt any of the 
two given alternatives. 
 
SECTION A 
 
1. How do cytokine barriers provide innate immunity in humans? [1] 
 
2. Write the dual purpose served by deoxyribonucleoside triphosphates in 
polymerisation. [1] 
 
3. Write the names of the following : [1] 
(a) A 15 mya primate that was ape-like 
(b) A 2 mya primate that lived in East African grasslands 
 
4. Mention the chemical change that proinsulin undergoes, to be able to act as 
mature insulin. [1] 
 
5. Name two diseases whose spread can be controlled by the eradication of Aedes 
mosquitoes. [1] 
 
  
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
SECTION B 
6. How did a citizen group called Friends of Arcata Marsh, Arcata, California, USA, 
help to improve water quality of the marshland using Integrated Waste Water 
Treatment? Explain in four steps. [2] 
 
7. Your advice is sought to improve the nitrogen content of the soil to be used for 
cultivation of a non-leguminous terrestrial crop. [2] 
(a) Recommend two microbes that can enrich the soil with nitrogen.  
(b) Why do leguminous crops not require such enrichment of the soil? 
 
8. You have obtained a high yielding variety of tomato. Name and explain the 
procedure that ensures retention of the desired characteristics repeatedly in 
large populations of future generations of the tomato crop. [2] 
 
9.   
(a) Name the source plant of heroin drug. How is it obtained from the plant? 
(b) Write the effects of heroin on the human body. [2] 
 
10. With the help of an algebraic equation, how did Hardy-Weinberg explain that in 
a given population the frequency of occurrence of alleles of a gene is supposed 
to remain the same through generations? [2] 
OR 
Although a prokaryotic cell has no defined nucleus, yet DNA is not scattered 
throughout the cell. Explain. 
 
  
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
SECTION C 
11.  
(a) Differentiate between analogous and homologous structures.  
(b) Select and write analogous structures from the list given below: [3] 
(i) Wings of butterfly and birds. 
(ii) Vertebrate heads 
(iii) Tendrils of bougainvillea and cucurbita 
(iv) Tubers of sweet potato and potato 
 
12. How has the use of Agrobacterium as vectors helped in controlling Meloidegyne 
incognitia infestation in tobacco plants? Explain in correct sequence. [3] 
 
13.  
(a) “India has greater ecosystem diversity than Norway”. Do you agree with the 
statement? Give reasons in support of your answer. 
(b) Write the difference between genetic biodiversity and species biodiversity 
that exists at all the levels of biological organization. [3] 
OR 
Explain the effect on the characteristics of a river when urban sewage is 
discharged into it. [3] 
14. Explain the mechanism of ‘sex determination’ in birds. How does it differ from 
that of human beings? [3] 
 
15. Explain out-breeding, out-crossing and cross-breeding practices in animal 
husbandry. [3] 
 
16.   
(a) Organic farmers prefer biological control of diseases and pests to the use of 
chemicals for the same purpose. Justify. 
(b) Give an example of a bacterium, a fungus and an insect that are used as 
biocontrol agents. [3] 
 
17.  
(a) How has the development of bioreactor helped biotechnology? 
(b) Name the most commonly used bioreactor and describe its working. [3] 
 
18. Explain the roles of the following with the help of an example each in 
recombinant DNA technology: [3] 
(a) Restriction Enzymes  
(b) Plasmids 
 
19. Differentiate between parthenocarpy and parthenogenesis. Give one example 
of each. [3] 
 
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
20. Medically it is advised to all young mothers that breastfeeding is the best for 
their newborn babies. Do you agree? Give reasons in support of your answer.[3] 
 
21. Draw a diagram of a mature human sperm. Label any three parts and write 
their functions. [3] 
 
22.  
(a) Expand VNTR and describe its role in DNA fingerprinting 
(b) List any two applications of DNA fingerprinting technique. [3] 
 
  
  
 
CBSE XII  |  Biology 
Board Paper 2018 – All India – Set 3 
 
       
SECTION D 
23. Looking at the deteriorating air quality because of air pollution in many cities 
of the country, the citizens are very much worried and concerned about their 
health. The doctors have declared health emergency in the cities where the air 
quality is very severely poor. [4] 
(a) Mention any two major causes of air pollution.  
(b) Write any two harmful effects of air pollution to plants and humans. 
(c) As a captain of your school Eco-club, suggest any two programmes you 
would plan to organise in the school so as to bring awareness among the 
students on how to check air pollution in and around the school.