Chemistry: CBSE Sample Question Paper (2019-20) | Chemistry for Grade 12 PDF Download

 Page 1


1	
	
Sample Question paper 
CLASS- XII 
BIO-TECHNOLOGY (045) 
SESSION 2019-20 
 
Time allowed: 3 hours                                                                               Maximum Marks: 70 
General Instructions: 
(i)    The question paper comprises four Sections – A, B, C and D. Attempt all the  Sections. 
(ii)   All questions are compulsory. 
(iii) There is no overall choice. However, an internal choice has been provided in five 
questions   of one mark, three questions of two marks, three questions of  three marks 
and three questions of five marks. You have to attempt only one of the choices in such 
questions. Questions paper contains four sections A, B, C and D. 
(iv) Question numbers 1 to 7 are very short answer questions carrying 1 mark each. 
Question numbers 8 to 12 are multiple choice questions carrying 1 mark each 
(v)   Question numbers 13 to 19 are short answer questions, carrying 2 marks each. 
(vi)  Question numbers 20 to 26 are also short answer questions, carrying 3 marks each. 
(vii) Question numbers 27 to 30 are long answer questions, carrying 5 marks each. 
(viii) Use of calculators is not permitted. However, you may use log tables, if necessary. 
 
 
 
 
SECTION A 
	
 
 
1 Name any two scientists involved in designing the first recombinant DNA 
molecule. 
 
1 
2 Write any two properties which can be improved  through protein engineering  
 
  
1 
3 Transgenic plants have been developed to survive in saline habitat. Which 
technique might have been used to develop such plants? 
 
 
 
1 
4 Which vector was used in the first cloning experiment involving mammalian cell? 
OR 
How does a modification enzyme protect its own DNA from digestion? 
	
 
1 
5 What was the strategy behind Human Genome Project? 
 
1 
6. An enriched medium containing salts, glucose, proteins and vitamins was made 
and a commercially available animal cell line was introduced. However, the cells 
began dying. What could be the reason behind it? 
OR 
 
1 
Page 2


1	
	
Sample Question paper 
CLASS- XII 
BIO-TECHNOLOGY (045) 
SESSION 2019-20 
 
Time allowed: 3 hours                                                                               Maximum Marks: 70 
General Instructions: 
(i)    The question paper comprises four Sections – A, B, C and D. Attempt all the  Sections. 
(ii)   All questions are compulsory. 
(iii) There is no overall choice. However, an internal choice has been provided in five 
questions   of one mark, three questions of two marks, three questions of  three marks 
and three questions of five marks. You have to attempt only one of the choices in such 
questions. Questions paper contains four sections A, B, C and D. 
(iv) Question numbers 1 to 7 are very short answer questions carrying 1 mark each. 
Question numbers 8 to 12 are multiple choice questions carrying 1 mark each 
(v)   Question numbers 13 to 19 are short answer questions, carrying 2 marks each. 
(vi)  Question numbers 20 to 26 are also short answer questions, carrying 3 marks each. 
(vii) Question numbers 27 to 30 are long answer questions, carrying 5 marks each. 
(viii) Use of calculators is not permitted. However, you may use log tables, if necessary. 
 
 
 
 
SECTION A 
	
 
 
1 Name any two scientists involved in designing the first recombinant DNA 
molecule. 
 
1 
2 Write any two properties which can be improved  through protein engineering  
 
  
1 
3 Transgenic plants have been developed to survive in saline habitat. Which 
technique might have been used to develop such plants? 
 
 
 
1 
4 Which vector was used in the first cloning experiment involving mammalian cell? 
OR 
How does a modification enzyme protect its own DNA from digestion? 
	
 
1 
5 What was the strategy behind Human Genome Project? 
 
1 
6. An enriched medium containing salts, glucose, proteins and vitamins was made 
and a commercially available animal cell line was introduced. However, the cells 
began dying. What could be the reason behind it? 
OR 
 
1 
2	
	
What   is A in the flow chart? 
 
 
 
7.  Margaret Dayhoff observed that protein sequences undergo variation according 
to certain patterns. Write any one such pattern. 
OR 
What is the underlying principle of “Molecular evolution”? 
 
1 
8.  Crystallisation is not required due to the advent of which of the following new 
technique. 
a) X-ray crystallography 
b) NMR 
c) Sanger’s method of protein sequencing  
 d) Edman’s method of protein sequencing 
 
1 
9.  Optimum pH for plant tissue culture medium is- 
a) 7.5                    c) 8 
b) 5.7                    d) 8.5 
 
1 
10. The single letter codes for Tyrosine and Asparagine are 
a) N and Y 
b) A and T 
c) T and A 
d) Y and N 
 
1 
11. The disease due to the deficiency of an enzyme Adenosine Deaminase (ADA) is 
a) SCID 
b) Thallasemia 
c) Haemophilia  
d) Mad cow disease 
 
1 
12 Question numbers 12(i) to 12(iv) are based on the following text on 
characterization of Cell Lines:  
In order to analyze the growth characteristics of a particular cell type or cell line, 
a growth curve can be established from which one can obtain a population 
doubling time, a lag time, and a saturation density. A growth curve generally will 
show the cell population's lag phase, that is, the time it takes for the cells to 
recover from subculture, attach, and spread; the log phase, in which the cell 
 
Page 3


1	
	
Sample Question paper 
CLASS- XII 
BIO-TECHNOLOGY (045) 
SESSION 2019-20 
 
Time allowed: 3 hours                                                                               Maximum Marks: 70 
General Instructions: 
(i)    The question paper comprises four Sections – A, B, C and D. Attempt all the  Sections. 
(ii)   All questions are compulsory. 
(iii) There is no overall choice. However, an internal choice has been provided in five 
questions   of one mark, three questions of two marks, three questions of  three marks 
and three questions of five marks. You have to attempt only one of the choices in such 
questions. Questions paper contains four sections A, B, C and D. 
(iv) Question numbers 1 to 7 are very short answer questions carrying 1 mark each. 
Question numbers 8 to 12 are multiple choice questions carrying 1 mark each 
(v)   Question numbers 13 to 19 are short answer questions, carrying 2 marks each. 
(vi)  Question numbers 20 to 26 are also short answer questions, carrying 3 marks each. 
(vii) Question numbers 27 to 30 are long answer questions, carrying 5 marks each. 
(viii) Use of calculators is not permitted. However, you may use log tables, if necessary. 
 
 
 
 
SECTION A 
	
 
 
1 Name any two scientists involved in designing the first recombinant DNA 
molecule. 
 
1 
2 Write any two properties which can be improved  through protein engineering  
 
  
1 
3 Transgenic plants have been developed to survive in saline habitat. Which 
technique might have been used to develop such plants? 
 
 
 
1 
4 Which vector was used in the first cloning experiment involving mammalian cell? 
OR 
How does a modification enzyme protect its own DNA from digestion? 
	
 
1 
5 What was the strategy behind Human Genome Project? 
 
1 
6. An enriched medium containing salts, glucose, proteins and vitamins was made 
and a commercially available animal cell line was introduced. However, the cells 
began dying. What could be the reason behind it? 
OR 
 
1 
2	
	
What   is A in the flow chart? 
 
 
 
7.  Margaret Dayhoff observed that protein sequences undergo variation according 
to certain patterns. Write any one such pattern. 
OR 
What is the underlying principle of “Molecular evolution”? 
 
1 
8.  Crystallisation is not required due to the advent of which of the following new 
technique. 
a) X-ray crystallography 
b) NMR 
c) Sanger’s method of protein sequencing  
 d) Edman’s method of protein sequencing 
 
1 
9.  Optimum pH for plant tissue culture medium is- 
a) 7.5                    c) 8 
b) 5.7                    d) 8.5 
 
1 
10. The single letter codes for Tyrosine and Asparagine are 
a) N and Y 
b) A and T 
c) T and A 
d) Y and N 
 
1 
11. The disease due to the deficiency of an enzyme Adenosine Deaminase (ADA) is 
a) SCID 
b) Thallasemia 
c) Haemophilia  
d) Mad cow disease 
 
1 
12 Question numbers 12(i) to 12(iv) are based on the following text on 
characterization of Cell Lines:  
In order to analyze the growth characteristics of a particular cell type or cell line, 
a growth curve can be established from which one can obtain a population 
doubling time, a lag time, and a saturation density. A growth curve generally will 
show the cell population's lag phase, that is, the time it takes for the cells to 
recover from subculture, attach, and spread; the log phase, in which the cell 
 
3	
	
number begins to increase exponentially and a plateau phase, in which the 
growth rate slows or stops due to depletion of growth factors and nutrients.  
 
 
(i). Beyond what cell concentration , saturation density  is achieved ?  
a)  > 10
4 
 cells /ml 
b) 10
4  
 to 10
5  
 cells /ml 
c) > 10
5
 cells /ml 
d) > 10
6 
 cells /ml 
 
1 
(ii). There is no increase in the cell concentration in the lag phase due to the 
following reasons: 
a) Exhaustion of the medium. 
b) Space constraint 
c) Both “a” and “b” 
d) Acclimatization to the new environment. 
 
1 
(iii). In which phase of growth is the specific growth rate of animal cell calculated? 
a) Log phase  
b) Lag phase 
c) Stationary phase  
d) Decline phase. 
 
1 
(iv) A student adds antibiotic to the animal cell culture medium and still obtains the 
same growth curve .The probable explanation for it will be: 
a) Antibiotics add growth factors and hormones in the medium 
b) Antibiotics provide serum for the growth of animal cells. 
c) Antibiotics enhance the nutrient content of the medium. 
d) Antibiotics don’t have any affect on animal cells 
1 
 
Page 4


1	
	
Sample Question paper 
CLASS- XII 
BIO-TECHNOLOGY (045) 
SESSION 2019-20 
 
Time allowed: 3 hours                                                                               Maximum Marks: 70 
General Instructions: 
(i)    The question paper comprises four Sections – A, B, C and D. Attempt all the  Sections. 
(ii)   All questions are compulsory. 
(iii) There is no overall choice. However, an internal choice has been provided in five 
questions   of one mark, three questions of two marks, three questions of  three marks 
and three questions of five marks. You have to attempt only one of the choices in such 
questions. Questions paper contains four sections A, B, C and D. 
(iv) Question numbers 1 to 7 are very short answer questions carrying 1 mark each. 
Question numbers 8 to 12 are multiple choice questions carrying 1 mark each 
(v)   Question numbers 13 to 19 are short answer questions, carrying 2 marks each. 
(vi)  Question numbers 20 to 26 are also short answer questions, carrying 3 marks each. 
(vii) Question numbers 27 to 30 are long answer questions, carrying 5 marks each. 
(viii) Use of calculators is not permitted. However, you may use log tables, if necessary. 
 
 
 
 
SECTION A 
	
 
 
1 Name any two scientists involved in designing the first recombinant DNA 
molecule. 
 
1 
2 Write any two properties which can be improved  through protein engineering  
 
  
1 
3 Transgenic plants have been developed to survive in saline habitat. Which 
technique might have been used to develop such plants? 
 
 
 
1 
4 Which vector was used in the first cloning experiment involving mammalian cell? 
OR 
How does a modification enzyme protect its own DNA from digestion? 
	
 
1 
5 What was the strategy behind Human Genome Project? 
 
1 
6. An enriched medium containing salts, glucose, proteins and vitamins was made 
and a commercially available animal cell line was introduced. However, the cells 
began dying. What could be the reason behind it? 
OR 
 
1 
2	
	
What   is A in the flow chart? 
 
 
 
7.  Margaret Dayhoff observed that protein sequences undergo variation according 
to certain patterns. Write any one such pattern. 
OR 
What is the underlying principle of “Molecular evolution”? 
 
1 
8.  Crystallisation is not required due to the advent of which of the following new 
technique. 
a) X-ray crystallography 
b) NMR 
c) Sanger’s method of protein sequencing  
 d) Edman’s method of protein sequencing 
 
1 
9.  Optimum pH for plant tissue culture medium is- 
a) 7.5                    c) 8 
b) 5.7                    d) 8.5 
 
1 
10. The single letter codes for Tyrosine and Asparagine are 
a) N and Y 
b) A and T 
c) T and A 
d) Y and N 
 
1 
11. The disease due to the deficiency of an enzyme Adenosine Deaminase (ADA) is 
a) SCID 
b) Thallasemia 
c) Haemophilia  
d) Mad cow disease 
 
1 
12 Question numbers 12(i) to 12(iv) are based on the following text on 
characterization of Cell Lines:  
In order to analyze the growth characteristics of a particular cell type or cell line, 
a growth curve can be established from which one can obtain a population 
doubling time, a lag time, and a saturation density. A growth curve generally will 
show the cell population's lag phase, that is, the time it takes for the cells to 
recover from subculture, attach, and spread; the log phase, in which the cell 
 
3	
	
number begins to increase exponentially and a plateau phase, in which the 
growth rate slows or stops due to depletion of growth factors and nutrients.  
 
 
(i). Beyond what cell concentration , saturation density  is achieved ?  
a)  > 10
4 
 cells /ml 
b) 10
4  
 to 10
5  
 cells /ml 
c) > 10
5
 cells /ml 
d) > 10
6 
 cells /ml 
 
1 
(ii). There is no increase in the cell concentration in the lag phase due to the 
following reasons: 
a) Exhaustion of the medium. 
b) Space constraint 
c) Both “a” and “b” 
d) Acclimatization to the new environment. 
 
1 
(iii). In which phase of growth is the specific growth rate of animal cell calculated? 
a) Log phase  
b) Lag phase 
c) Stationary phase  
d) Decline phase. 
 
1 
(iv) A student adds antibiotic to the animal cell culture medium and still obtains the 
same growth curve .The probable explanation for it will be: 
a) Antibiotics add growth factors and hormones in the medium 
b) Antibiotics provide serum for the growth of animal cells. 
c) Antibiotics enhance the nutrient content of the medium. 
d) Antibiotics don’t have any affect on animal cells 
1 
 
4	
	
 
 
SECTION B 
 
13 Differentiate between synthetic and complex medium used for microbial culture. 
 
2 
14 How can LEU 2 gene be used as a selectable marker? 2 
 
15 On the basis of the table given below, state your observations pertaining to the 
organisation features of the organism. 
 
ORGANISM No. of 
chromoso
mes 
Genome size in 
base pairs 
The 
number of 
predicted 
genes 
Part of the 
genome that 
encodes for 
proteins 
Worm Caenorhabditis 
elegans 
6 100,000,000 19,000 27% 
Human Homo sapiens 23 3,000,000,000 20,000-
25,000 
<5% 
Fly Drosophila 
melanogaster 
4 175,000,000-
196,000,000 
13600 20% 
                                   
 
2 
16 Differentiate between somaclones and gametoclones. Who proposed the term 
somaclones? 
 
2 
 
17 a) What are the various interactions that stabilize a folded protein? 
b) How can the stability of protein be changed? 
 
2 
18 What are various biosafety issues in microbial technology? 
OR 
The laboratory scale design cannot be scaled up to industrial scale directly. 
Write any two points that need to be considered while going  for industrial scale 
production. 
 
2 
19 In a variant of chymotrypsin, Asp 102 is replaced by Glu 102. Do you expect the 
enzyme to retain activity? Schematically indicate the role of amino acid residues 
participating in catalysis. 
OR 
Thalassemic patients produce excess alpha or beta subunits of haemoglobin 
leading to impaired oxygen-binding capacity by their erythrocytes. How can it be 
determined as to which subunit is produced in excess? 
2 
 
SECTION C 
 
20 Recombinant insulin is produced at 100 mg/l by E. coli at a cell concentration of 1 
g/l. Calculate the volume of reactor (size of the fermentor) needed to produce 1 
kilogram of insulin in the following conditions: 
 
(a) When the cell concentration is 1 g/l and insulin production is 100 mg /l. 
(b) When the cell concentration is 50 g/l and insulin production is 100 mg /l. 
(c) When the cell concentration is 50 g/l and insulin production is 500 mg /l  
 
3 
Page 5


1	
	
Sample Question paper 
CLASS- XII 
BIO-TECHNOLOGY (045) 
SESSION 2019-20 
 
Time allowed: 3 hours                                                                               Maximum Marks: 70 
General Instructions: 
(i)    The question paper comprises four Sections – A, B, C and D. Attempt all the  Sections. 
(ii)   All questions are compulsory. 
(iii) There is no overall choice. However, an internal choice has been provided in five 
questions   of one mark, three questions of two marks, three questions of  three marks 
and three questions of five marks. You have to attempt only one of the choices in such 
questions. Questions paper contains four sections A, B, C and D. 
(iv) Question numbers 1 to 7 are very short answer questions carrying 1 mark each. 
Question numbers 8 to 12 are multiple choice questions carrying 1 mark each 
(v)   Question numbers 13 to 19 are short answer questions, carrying 2 marks each. 
(vi)  Question numbers 20 to 26 are also short answer questions, carrying 3 marks each. 
(vii) Question numbers 27 to 30 are long answer questions, carrying 5 marks each. 
(viii) Use of calculators is not permitted. However, you may use log tables, if necessary. 
 
 
 
 
SECTION A 
	
 
 
1 Name any two scientists involved in designing the first recombinant DNA 
molecule. 
 
1 
2 Write any two properties which can be improved  through protein engineering  
 
  
1 
3 Transgenic plants have been developed to survive in saline habitat. Which 
technique might have been used to develop such plants? 
 
 
 
1 
4 Which vector was used in the first cloning experiment involving mammalian cell? 
OR 
How does a modification enzyme protect its own DNA from digestion? 
	
 
1 
5 What was the strategy behind Human Genome Project? 
 
1 
6. An enriched medium containing salts, glucose, proteins and vitamins was made 
and a commercially available animal cell line was introduced. However, the cells 
began dying. What could be the reason behind it? 
OR 
 
1 
2	
	
What   is A in the flow chart? 
 
 
 
7.  Margaret Dayhoff observed that protein sequences undergo variation according 
to certain patterns. Write any one such pattern. 
OR 
What is the underlying principle of “Molecular evolution”? 
 
1 
8.  Crystallisation is not required due to the advent of which of the following new 
technique. 
a) X-ray crystallography 
b) NMR 
c) Sanger’s method of protein sequencing  
 d) Edman’s method of protein sequencing 
 
1 
9.  Optimum pH for plant tissue culture medium is- 
a) 7.5                    c) 8 
b) 5.7                    d) 8.5 
 
1 
10. The single letter codes for Tyrosine and Asparagine are 
a) N and Y 
b) A and T 
c) T and A 
d) Y and N 
 
1 
11. The disease due to the deficiency of an enzyme Adenosine Deaminase (ADA) is 
a) SCID 
b) Thallasemia 
c) Haemophilia  
d) Mad cow disease 
 
1 
12 Question numbers 12(i) to 12(iv) are based on the following text on 
characterization of Cell Lines:  
In order to analyze the growth characteristics of a particular cell type or cell line, 
a growth curve can be established from which one can obtain a population 
doubling time, a lag time, and a saturation density. A growth curve generally will 
show the cell population's lag phase, that is, the time it takes for the cells to 
recover from subculture, attach, and spread; the log phase, in which the cell 
 
3	
	
number begins to increase exponentially and a plateau phase, in which the 
growth rate slows or stops due to depletion of growth factors and nutrients.  
 
 
(i). Beyond what cell concentration , saturation density  is achieved ?  
a)  > 10
4 
 cells /ml 
b) 10
4  
 to 10
5  
 cells /ml 
c) > 10
5
 cells /ml 
d) > 10
6 
 cells /ml 
 
1 
(ii). There is no increase in the cell concentration in the lag phase due to the 
following reasons: 
a) Exhaustion of the medium. 
b) Space constraint 
c) Both “a” and “b” 
d) Acclimatization to the new environment. 
 
1 
(iii). In which phase of growth is the specific growth rate of animal cell calculated? 
a) Log phase  
b) Lag phase 
c) Stationary phase  
d) Decline phase. 
 
1 
(iv) A student adds antibiotic to the animal cell culture medium and still obtains the 
same growth curve .The probable explanation for it will be: 
a) Antibiotics add growth factors and hormones in the medium 
b) Antibiotics provide serum for the growth of animal cells. 
c) Antibiotics enhance the nutrient content of the medium. 
d) Antibiotics don’t have any affect on animal cells 
1 
 
4	
	
 
 
SECTION B 
 
13 Differentiate between synthetic and complex medium used for microbial culture. 
 
2 
14 How can LEU 2 gene be used as a selectable marker? 2 
 
15 On the basis of the table given below, state your observations pertaining to the 
organisation features of the organism. 
 
ORGANISM No. of 
chromoso
mes 
Genome size in 
base pairs 
The 
number of 
predicted 
genes 
Part of the 
genome that 
encodes for 
proteins 
Worm Caenorhabditis 
elegans 
6 100,000,000 19,000 27% 
Human Homo sapiens 23 3,000,000,000 20,000-
25,000 
<5% 
Fly Drosophila 
melanogaster 
4 175,000,000-
196,000,000 
13600 20% 
                                   
 
2 
16 Differentiate between somaclones and gametoclones. Who proposed the term 
somaclones? 
 
2 
 
17 a) What are the various interactions that stabilize a folded protein? 
b) How can the stability of protein be changed? 
 
2 
18 What are various biosafety issues in microbial technology? 
OR 
The laboratory scale design cannot be scaled up to industrial scale directly. 
Write any two points that need to be considered while going  for industrial scale 
production. 
 
2 
19 In a variant of chymotrypsin, Asp 102 is replaced by Glu 102. Do you expect the 
enzyme to retain activity? Schematically indicate the role of amino acid residues 
participating in catalysis. 
OR 
Thalassemic patients produce excess alpha or beta subunits of haemoglobin 
leading to impaired oxygen-binding capacity by their erythrocytes. How can it be 
determined as to which subunit is produced in excess? 
2 
 
SECTION C 
 
20 Recombinant insulin is produced at 100 mg/l by E. coli at a cell concentration of 1 
g/l. Calculate the volume of reactor (size of the fermentor) needed to produce 1 
kilogram of insulin in the following conditions: 
 
(a) When the cell concentration is 1 g/l and insulin production is 100 mg /l. 
(b) When the cell concentration is 50 g/l and insulin production is 100 mg /l. 
(c) When the cell concentration is 50 g/l and insulin production is 500 mg /l  
 
3 
5	
	
21 Schematically explain the formation of recombinant plasmid. 
OR 
Students of Class XII visited Microbial Type Culture Collection, Chandigarh and 
observed microbial cultures of Providencia stuartii, Streptomyces albus and 
Haemophilus aegyptus. Name the restriction enzymes obtained from them and 
also specify their restriction sites. 
 
3 
22 Complete the table by filling the mode of action / functional properties  
indicated as A, B, C, D, E and F  
 
Functional Property Mode of action 
Whipping/Foaming A 
B Formation and stabilization of fat emulsions 
C Protein matrix formation and setting 
Viscosity D 
E Hydrogen bonding of water; entrapment of water 
Solubility F 
 
3 
 
23 
 
Selection is an important step in genetic engineering. You are given ampicillin 
and tetracycline antibiotics. Using these antibiotics, which selection technique 
could be used to differentiate between recombinant and non-recombinant cells? 
 
 
3 
24 Write any six applications of plant genetic engineering. 
 
3 
25 How does the metagenomics approach help to identify novel genes present in 
the environment? Explain the process. 
OR 
What is a pilot plant? Why is it necessary to validate a process in a pilot plant 
before commercial scale production in a bioprocess industry? 
 
3 
26 Given below are few transgenic crops approved by US food and drug 
administration along with the improved character. Name the genes A to F 
introduced for the improved character. 
 
 
Crop Gene Improved character 
Canola A Hybrid  production  
Corn B Insect resistance  
Cotton C Insect resistance 
Papaya D Virus resistance 
Potato  E Insect and virus control 
Soyabean F Weed Control 
                                 
3 
SECTION D 
27 Mutation is an alteration in any of the base of a DNA sequence sometimes 
leading to a defective protein or prematurely terminated non-functional protein. It 
can be spontaneous or induced. Diagrammatically explain how mutation can be 
induced in a gene. 
OR 
A bacteriophage is known to infect E.coli with pili. How can it be modified to 
serve as a suitable vector?  
5