CBSE Biology All India Past year paper (Set - 2) - 2015, Class 12 | Additional Study Material for NEET PDF Download

 Page 1


  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
CBSE 
Class XII Biology 
Board Paper – 2015 – All India (Set 2) 
Time: 3 hrs Total 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. List two advantages of the use of unleaded petrol in automobiles as fuel. [1] 
 
2. Retroviruses have no DNA. However, the DNA of the infected host cell does possess viral 
DNA. How is it possible? [1] 
 
3. State the cause of adenosine deaminase enzyme deficiency. [1] 
 
4. What is a cistron? [1] 
 
5. How many chromosomes do drones of honey bee possess? Name the type of cell division 
involved in the production of sperms by them. [1] 
 
  
Page 2


  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
CBSE 
Class XII Biology 
Board Paper – 2015 – All India (Set 2) 
Time: 3 hrs Total 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. List two advantages of the use of unleaded petrol in automobiles as fuel. [1] 
 
2. Retroviruses have no DNA. However, the DNA of the infected host cell does possess viral 
DNA. How is it possible? [1] 
 
3. State the cause of adenosine deaminase enzyme deficiency. [1] 
 
4. What is a cistron? [1] 
 
5. How many chromosomes do drones of honey bee possess? Name the type of cell division 
involved in the production of sperms by them. [1] 
 
  
  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
SECTION B 
 
6. What is mutualism? Mention any two examples where the organisms involved are 
commercially exploited in agriculture. 
OR 
 List any four techniques where the principle of ex situ conservation of biodiversity has been 
employed. [2] 
 
7.   [2] 
(a) Why are the plants raised through micropropagation termed as somaclones? 
(b) Mention two advantages of this technique.  
 
8. Explain the process of secondary treatment given to the primary effluent up to the point it 
shows significant change in the level of biological oxygen demand (BOD) it. [2] 
 
9.    [2] 
(a) Select the analogous structures from the combination given below: 
(i) Forelimbs of whales and bats 
(ii) Eyes of octopus and mammals 
(iii) Tuber of sweet potato and potato 
(iv) Tuber of Bougainvillea and tendrils of Cucurbita 
(b) State the kind of evolution they represent 
 
10. A moss plant is unable to complete its life cycle in a dry environment. State two reasons. [2] 
 
SECTION C 
 
11. A heavily bleeding and bruised road accident victim was brought to a nursing home. The 
doctor immediately gave him an injection to protect him against a deadly disease. 
(a) Write what did the doctor inject into the patient’s body. 
(b) How do you think this injection would protect the patient against the diseases? 
(c) Name the disease against which this injection was given and the kind of immunity it 
provides.    [3] 
 
12. Explain the significance of satellite DNA fingerprinting technique.   [3] 
 
13. What does the following equation represent? Explain. [3] 
       p
2 
+ 2 pq + q
2
 = 1 
 
 
 
 
Page 3


  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
CBSE 
Class XII Biology 
Board Paper – 2015 – All India (Set 2) 
Time: 3 hrs Total 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. List two advantages of the use of unleaded petrol in automobiles as fuel. [1] 
 
2. Retroviruses have no DNA. However, the DNA of the infected host cell does possess viral 
DNA. How is it possible? [1] 
 
3. State the cause of adenosine deaminase enzyme deficiency. [1] 
 
4. What is a cistron? [1] 
 
5. How many chromosomes do drones of honey bee possess? Name the type of cell division 
involved in the production of sperms by them. [1] 
 
  
  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
SECTION B 
 
6. What is mutualism? Mention any two examples where the organisms involved are 
commercially exploited in agriculture. 
OR 
 List any four techniques where the principle of ex situ conservation of biodiversity has been 
employed. [2] 
 
7.   [2] 
(a) Why are the plants raised through micropropagation termed as somaclones? 
(b) Mention two advantages of this technique.  
 
8. Explain the process of secondary treatment given to the primary effluent up to the point it 
shows significant change in the level of biological oxygen demand (BOD) it. [2] 
 
9.    [2] 
(a) Select the analogous structures from the combination given below: 
(i) Forelimbs of whales and bats 
(ii) Eyes of octopus and mammals 
(iii) Tuber of sweet potato and potato 
(iv) Tuber of Bougainvillea and tendrils of Cucurbita 
(b) State the kind of evolution they represent 
 
10. A moss plant is unable to complete its life cycle in a dry environment. State two reasons. [2] 
 
SECTION C 
 
11. A heavily bleeding and bruised road accident victim was brought to a nursing home. The 
doctor immediately gave him an injection to protect him against a deadly disease. 
(a) Write what did the doctor inject into the patient’s body. 
(b) How do you think this injection would protect the patient against the diseases? 
(c) Name the disease against which this injection was given and the kind of immunity it 
provides.    [3] 
 
12. Explain the significance of satellite DNA fingerprinting technique.   [3] 
 
13. What does the following equation represent? Explain. [3] 
       p
2 
+ 2 pq + q
2
 = 1 
 
 
 
 
  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
14. Two independent monohybrid crosses were carried out involving a tall pa plant with a 
dwarf pea plant. In the first cross, the offspring population has equal number of tall and 
dwarf plants, whereas in the second cross it was different. Work out the crosses and 
explain giving reasons for the difference in the offspring population.   [3] 
 
15. State what is apomixis comment on its significance? How can it be commercially used? [3] 
 
16. State the medicinal value and the bioactive molecules produced by Streptococcus, Monascus 
and Trichoderma. [3] 
OR 
What are methanogens? How do they help to generate biogas? 
 
17. Describe any three potential applications of genetically modified plants. [3] 
 
18. How did an American company, Eli Lilly use the knowledge of r-DNA technology to produce 
human insulin? [3] 
 
19. Explain co-evolution with reference to parasites and their hosts. Mention any four special 
adaptive evolved in parasites for their parasite mode of life [3] 
 
20. Rearrange the following in the correct sequence to accomplish an important 
biotechnological reaction: [3] 
(a) In vitro synthesis of copies of DNA of interest 
(b) Chemically synthesised oligonucleotides 
(c) Enzyme DNA-polymerase 
(d) Complementary region of DNA 
(e) Genomic DNA template 
(f) Nucleotides provided 
(g) Primers 
(h) Thermostable DNA-polymerase (from Thermus aquaticus) 
(i) Denaturation of ds-DNA 
 
21. With the help of a flow-chart exhibit the events of eutrophication. [3] 
 
22. Enumerate any six essentials of good, effective dairy farm management practices. [3] 
 
 
 
 
 
 
 
Page 4


  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
CBSE 
Class XII Biology 
Board Paper – 2015 – All India (Set 2) 
Time: 3 hrs Total 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. List two advantages of the use of unleaded petrol in automobiles as fuel. [1] 
 
2. Retroviruses have no DNA. However, the DNA of the infected host cell does possess viral 
DNA. How is it possible? [1] 
 
3. State the cause of adenosine deaminase enzyme deficiency. [1] 
 
4. What is a cistron? [1] 
 
5. How many chromosomes do drones of honey bee possess? Name the type of cell division 
involved in the production of sperms by them. [1] 
 
  
  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
SECTION B 
 
6. What is mutualism? Mention any two examples where the organisms involved are 
commercially exploited in agriculture. 
OR 
 List any four techniques where the principle of ex situ conservation of biodiversity has been 
employed. [2] 
 
7.   [2] 
(a) Why are the plants raised through micropropagation termed as somaclones? 
(b) Mention two advantages of this technique.  
 
8. Explain the process of secondary treatment given to the primary effluent up to the point it 
shows significant change in the level of biological oxygen demand (BOD) it. [2] 
 
9.    [2] 
(a) Select the analogous structures from the combination given below: 
(i) Forelimbs of whales and bats 
(ii) Eyes of octopus and mammals 
(iii) Tuber of sweet potato and potato 
(iv) Tuber of Bougainvillea and tendrils of Cucurbita 
(b) State the kind of evolution they represent 
 
10. A moss plant is unable to complete its life cycle in a dry environment. State two reasons. [2] 
 
SECTION C 
 
11. A heavily bleeding and bruised road accident victim was brought to a nursing home. The 
doctor immediately gave him an injection to protect him against a deadly disease. 
(a) Write what did the doctor inject into the patient’s body. 
(b) How do you think this injection would protect the patient against the diseases? 
(c) Name the disease against which this injection was given and the kind of immunity it 
provides.    [3] 
 
12. Explain the significance of satellite DNA fingerprinting technique.   [3] 
 
13. What does the following equation represent? Explain. [3] 
       p
2 
+ 2 pq + q
2
 = 1 
 
 
 
 
  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
14. Two independent monohybrid crosses were carried out involving a tall pa plant with a 
dwarf pea plant. In the first cross, the offspring population has equal number of tall and 
dwarf plants, whereas in the second cross it was different. Work out the crosses and 
explain giving reasons for the difference in the offspring population.   [3] 
 
15. State what is apomixis comment on its significance? How can it be commercially used? [3] 
 
16. State the medicinal value and the bioactive molecules produced by Streptococcus, Monascus 
and Trichoderma. [3] 
OR 
What are methanogens? How do they help to generate biogas? 
 
17. Describe any three potential applications of genetically modified plants. [3] 
 
18. How did an American company, Eli Lilly use the knowledge of r-DNA technology to produce 
human insulin? [3] 
 
19. Explain co-evolution with reference to parasites and their hosts. Mention any four special 
adaptive evolved in parasites for their parasite mode of life [3] 
 
20. Rearrange the following in the correct sequence to accomplish an important 
biotechnological reaction: [3] 
(a) In vitro synthesis of copies of DNA of interest 
(b) Chemically synthesised oligonucleotides 
(c) Enzyme DNA-polymerase 
(d) Complementary region of DNA 
(e) Genomic DNA template 
(f) Nucleotides provided 
(g) Primers 
(h) Thermostable DNA-polymerase (from Thermus aquaticus) 
(i) Denaturation of ds-DNA 
 
21. With the help of a flow-chart exhibit the events of eutrophication. [3] 
 
22. Enumerate any six essentials of good, effective dairy farm management practices. [3] 
 
 
 
 
 
 
 
  
 
CBSE XII  |  Biology 
Board Paper – 2015 – All India – Set 2 
 
     
 
SECTION D 
 
23. Your school has been selected by the Department of Education to organise and host and 
interschool seminar on ‘’Reproductive Health – Problems and Practices.’’ However, many 
parents are reluctant to permit their wards to attend it. Their argument is that the topic is 
‘’too embarrassing’’ 
 Put fourth four arguments with appropriate reasons and explanation to justify the topic to 
be very essential and timely [4] 
 
SECTION E 
 
24.   
(a) List the different attributes that a population has and not an individual organism. 
(b) What is population density? Explain any three different ways the population density 
can be measured, with the help of an example each. 
OR 
‘’It is often said that the pyramid of energy is always upright. On the other hand, the   
pyramid of biomass can be both upright and inverted.’’ Explain with the help of     examples 
of sketches. [4] 
 
25.   
(a) Plan an experiment and prepare a flow chart of the steps that you would follow to 
ensure that the seeds are formed only from the desired sets of pollen grains. Name the 
type of experiment that you carried out. 
(b) Write the importance of such experiments. [4] 
OR 
Describe the roles of pituitary and ovarian hormones during the menstrual cycle in a 
human female. 
 
26.   
(a) Why are colour-blindness and thalassaemia categorised as Mendelian disorders? Write 
the symptoms of these diseases seen in people suffering from them. 
(b) About 8% of human male population suffers from colour-blindness, whereas only about 
0.4% of human female population suffers from this disease. Write an explanation to 
show how it is possible. [4] 
OR 
Explain the process of transcription in prokaryotes. How is the process different in 
eukaryotes?