Rajasthan Board Class 12 Question Paper 2020 Biology

 Roll No.

No. of Questions – 30
No. of Printed Pages – 8 SS-42-Bio.
  (BIOLOGY)
  , 2020
 3¼ 
 56

     

GENERAL INSTRUCTIONS TO THE EXAMINEES :

(1)    -     

Candidate must write first his / her Roll No. on the question paper compulsorily.

(2)      

All the questions are compulsory.

(3)       -    

Write the answer to each question in the given answer-book only.

SS-42-Bio. [ Turn over

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(4)      ,         
For questions having more than one part, the answers to those parts are to be written
together in continuity.

(5) -    
       //      
    
If there is any error / difference / contradiction in Hindi & English versions of the
question paper, the question of Hindi version should be treated valid.

(6)      
 1 – 13 1

 14 – 24 2

 25 – 27 3

 28 – 30 4
Section Q. Nos. Marks per question
A 1 – 13 1
B 14 – 24 2
C 25 – 27 3
D 28 – 30 4

(7)   14, 27, 28, 29  30     
Question Nos. 14, 27, 28, 29 and 30 have internal choices.

3

 – 
SECTION – A

1.        
Write the name of four flower parts. ¼+¼+¼+¼ =1

2.                ?
Marsh spot disease of pea is caused by deficiency of which element in soil ? 1

3.       
Write two examples of impermeable membrane. ½+½=1

4.        
Write the name of a growth inhibiting hormone. 1

5.              
Write the name of Boll worm resistant genetically modified variety of cotton. 1

6.              ?
Which part of coconut fruit is used for yielding coconut oil ? 1

7.            ?
Which vitamin is synthesised by human skin ? 1

8.              ?
Which eye pigment helps animal to see in dim light ? 1

SS-42-Bio. [ Turn over

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9.    “C”         ?
Which hormone is synthesised by “C” cells of thyroid gland ? 1

10.          ...     ?
For prevention of which disease, a person should be vaccinated with T.A.B. ? 1

11.       
Write an example of hinge joint. 1

12. “”   
Explain “Gastrulation”. 1

13. ...     
Write the full form of E.E.G. 1

 - 
SECTION – B

14.          
          
Define bacteriophage and write one example of it. 1+1=2
OR
Write two importance of biotechnology in medical field.

15.          1+1=2
Write difference between estrus cycle and menstrual cycle.

5
16.                 
Write name of a species of honey-bee and write name of two appliances of apiculture.

1+½+½=2

17.             
Explain restriction fragment length polymorphism and write one use of it. 1+1=2

18.    ?              ?
What is biopesticide ? How Baccilus thuringiensis is used as biopesticide ? 1+1=2

19. -A      -B              :
-A -B
(A)  (i)   
(B)  (ii)   
(C)  (iii)   
(D)  (iv)    
Part – A contains the plant name and Part – B contains useful plant part related to them.
Match the following :

Part – A Part – B

(A) Munj (i) Dry flower buds

(B) Clove (ii) Leaves for fibres

(C) Black pepper (iii) Mature Crimocarp fruit

(D) Fennel (iv) Immature dry drupe fruit ½+½+½+½=2

SS-42-Bio. [ Turn over

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20.          
Explain two disorders related to heart and circulatory system. 1+1=2

21.           
Explain nomenclature of enzyme on the basis of chemical reaction. 2

22.     ?                
   ?
What is Kliekning ? In human embryonic stages, which organs are formed during third to
sixth week of gestation ? 1+1=2

23. -     
Explain co-dominance with example. 2

24.                    
Write the pathogen of Tetanus. Mention one symptom and a preventive measure of it.
1+½+½=2
 – 
SECTION – C

25.         
Describe the structure of cellular endosperm with diagram. 1+2=3

26. -     -    
Define crossing over. Explain crossing over with diagram. 1+1+1=3

27.              
              
Explain the osmosis and draw a labelled diagram of demonstration of osmosis by thistle
funnel. 2+1=3
OR
Explain lock and key theory of enzyme action and draw a labelled diagram of model.

7
 – 
SECTION – D

28. (i) -        ?
(ii) C4      
(iii) C4      
(i)     ?
(ii)      
(iii)       
(i) In which plants Hatch-Slack cycle takes place ?
(ii) Explain mechanism of C4 cycle.
(iii) Draw a line diagram of C4 cycle. 1+2+1=4
OR
(i) What is ammonification ?
(ii) Explain nitrification and dentrification.
(iii) Draw a line diagram of nitrogen cycle.

29. (i)          
(ii)      
(iii)     /    
(i)      
(ii)       
(iii)       
(i) Draw a labelled diagram of internal structure of human ear.
(ii) Explain the mechanism of hearing.
(iii) Write any two diseases/defects of ear. 1+2+1=4
OR
(i) Define reflex action.
(ii) Explain mechanism of reflex action.
(iii) Draw a line diagram of reflex action.

SS-42-Bio. [ Turn over

8
30. (i)          
(ii)        
(i)          
(ii)            
(i) Draw a labelled diagram of mechanism of inspiration and expiration.
(ii) Explain mechanism of inspiration and expiration. 1+3=4
OR
(i) Draw a labelled diagram of internal structure of human heart.
(ii) Describe any three diseases related to heart and circulatory system.

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