Kerala Plus One Question Paper 2025 Biology

KERALA BOARD

QUESTION
PAPER
2025
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Kerala Board of Public
Examinations

FY-326
Reg. No. : ......................................

Name : ...........................................

FIRST YEAR HIGHER SECONDARY EXAMINATION, MARCH 2025

Part – III Time : 2 Hours
BIOLOGY Cool-off time : 15 Minutes
(Botany & Zoology) Preparatory Time : 10 Minutes
Maximum : 60 Scores

General Instructions to Candidates :
 There is a ‘Cool-off time’ of 15 minutes in addition to the writing time. Further there is
a ‘10 minutes’ ‘Preparatory Time’ at the end of the Botany Examination and before the
commencement of Zoology Examination.
 Use the ‘Cool-off time’ to get familiar with questions and to plan your answers.
 Read questions carefully before answering.
 Read the instructions carefully.
 Calculations, figures and graphs should be shown in the answer sheet itself.
 Malayalam version of the questions is also provided.
 Give equations wherever necessary.
 Electronic devices except non-programmable calculators are not allowed in the
Examination Hall.
 
    15  ‘  ’ .
     
‘10 ’   .
 ‘  ’    
 .
      .
    .
  , , ,   
.
   .
    .
     
    .

FY-326 1 P.T.O.

PART – A
BOTANY
(Maximum : 30 Scores) Time : 1 Hour

I. Question 1 to 5. Answer any 3, each question carries 1 score. (3  1 = 3)

1. Diatoms belong to the following classifications : _____

(a) Chrysophytes (b) Protozoans

(c) Dianoflagelletes (d) Euglenoids

2. The stored food material present in Rhodophyceae is _____ .

3. Which type of venation do you observe in dicot leaf ?

4. Name the stage of Meiosis during which Synaptonemal complex is formed.

5. In the following growth curve, what does the number ‘2’ represent ?

II. Question 6 to 16. Answer any 9, each question carries 2 scores. (9  2 = 18)

6. What do the terms Phycobiont and Mycobiont signify ?

FY-326 2

PART – A
BOTANY
(Maximum : 30 Scores) Time : 1 Hour
I. 1  5    3  .
1  . (3  1 = 3)

1.     .
(a) 
  (b) 
(c)  (d) 

2.        .

3.        ?

4.      
.

5.    2     
.

II. 6  16    9  .
2  . (9  2 = 18)

6.  ,    
 ?

FY-326 3 P.T.O.

7. Match the following :

I II
a. Chlamydomonas – 1. Moss
b. Cycas – 2. Pteridophytes
c. Selaginella – 3. Algae
d. Shagnum – 4. Gymnosperm

8. Observe the figure and answer the following questions :

I. Name the parts (A) and (B)
II. Which parts of stomata constitute the stomatal apparatus ?

9. Identify the types of vascular bundles given below and label the parts.

FY-326 4

7.   :

I II
a.  – 1. 

b.  – 2. 

c.  – 3. 

d.  – 4.  

8.       
 :

I.  (A)  (B)  
II.     
  ?

9.      
  .

FY-326 5 P.T.O.

10. An accepted model of the structure of a cell membrane was proposed by Singer and

Nicolson.

(a) Name the model.

(b) List the 2 major biomolecules which this membrane is composed of.

(c) State one function of this membrane.

11. Find the odd one and justify your answer.

(a) Stroma, Grana, Cristae, Stroma lamellae.

(b) Chromatid, Fimbriae, Kinetochore, Centromere.

12. Expand the abbreviation RuBP. What is its role in Photosynthesis ?

13. In a C3 plant a light dependent cyclic process is occurring that require oxygen.

(a) Name the process.

(b) In this process instead of producing, it consume energy. Evaluate the statement.

14. Pyruvate undergoes an oxidative decarboxylation by a complex set of reactions before

entering the Krebs cycle.

(a) Name the compound formed from this reaction which then enters Krebs cycle.

(b) Name the enzyme that catalyses this reaction.

15. (a) What is bolting ?

(b) Which hormone is used for bolting ?

FY-326 6

10.       
 .
(a)     ?
(b)        ?
(c)     .

11.    .
(a) , , ,  
(b) , , , 

12. RuBP   .     ?

13. C3      
  .
(a)  .
(b)        
.   .

14.       
   

(a)  ,    
 ?
(b)     .

15. (a)    ?

(b)     ?
FY-326 7 P.T.O.

16. Observe the figure given below :

(a) Source of which plant hormone is indicated in the figure ?

(b) Write three roles of above identified hormone.

III. Question 17 to 20. Answer any 3, each question carries 3 scores. (3  3 = 9)

17. Observe the figures A and B.

(a) Identify the type of inflorescence A & B.

(b) Write any two difference between them.

FY-326 8

16.    .

(a)      ?

(b)    3  .

III. 17  20    3  .

3  . (3  3 = 9)

17.  A  B  

(a) A  B      .

(b)      .

FY-326 9 P.T.O.

18. Given below is the diagrammatic representation of a particular stage of mitosis.

(a) Identify the stage.
(b) Write any two features of this stage.
(c) Write any three significance of mitosis.

19. Diagrammatic representation of Hatch and Slack pathway is shown below. Analyse the
figure.

(a) Identify the cells A and B.
(b) Why this pathway is called C4 pathway ?
(c) Write any 3 advantages of C4 plants over C3 plants .
FY-326 10

18.          .

(a)   .
(b)     .
(c)   3  .

19.  &       .
      .

(a)  A  B  .
(b)   C4     ?
(c) C4  C3   3  .

FY-326 11 P.T.O.

20. Observe the incomplete schematic representation given below and answer the
questions.

(a) Identify this pathway common for both aerobic and anaerobic respiration.
(b) Complete the scheme by filling the boxes A, B, C and D.
(c) Mention the three ways in which different cells handle pyruvic acid produced by
this pathway.

FY-326 12

20.      
   .

(a)         ?
(b)  A, B, C, D  .
(c)        
3    ?

FY-326 13 P.T.O.

PART – B
ZOOLOGY
(Maximum : 30 Scores) Time : 1 Hour
I. Answer any 3 questions from 1 to 5. Each correct answer carry 1 score. (3  1 = 3)
1. Expand

(a) ICBN

(b) ICZN

2. Give suitable terms for the given.

(a) Respiration through skin (cuticle)

(b) Respiration through lungs

3. Inulin is a polymer of _____ .

4. Observe the given figures A and B. Identify and name them.

5. Cerebral hemispheres are connected by a tract of nerve fibres called _____ .

II. Answer any 9 questions from 6 to 16. Each correct answer carries 2 scores.

(9  2 = 18)

6. Write two external features that helps to identify male and female frogs.

FY-326 14

PART – B
ZOOLOGY
(Maximum : 30 Scores) Time : 1 Hour

I. 1  5    3  .
1  . (3  1 = 3)
1. .
(a) ICBN
(b) ICZN

2.    .
(a)   ()
(b)  

3.  _________   .

4. A, B     .

5.       
_________ .

II. 6  16     9 
.   2  . (9  2 = 18)
6.       
.

FY-326 15 P.T.O.

7. (a) Write the correct path of cardiac impulse.
Hints : AV Node, Purkinje fibres, SA Node, Bundle of His
(b) Why SA Node is called ‘Pacemaker’ ?

8. Observe the given figure and answer the questions.
Label A, B, C and D.

9. A few structures/organs of animals are listed below. Identify the phylum in which these
organs/structures are present.
(a) Radula
(b) Parapodia
(c) Comb plates
(d) Calcareous ossicles

10. Differentiate chondrichthyes and osteichthyes.

11. Complete the Table (Hints are given)
Granulocytes Hints
(A) – Monocytes
Neutrophil ................... Basophil
– Eosinophil
Function Percentage

– 20 – 25%
(B) – Phagocytic
60 – 65% 2 – 3% ...................
– Inflammatory response
Allergic
(C) (D) – 0.5 – 1%
................... response ...................

FY-326 16

7. (a)      
 .
Hints : AV Node, Purkinje fibres, SA Node, Bundle of His
(b) SA Node  ‘ ’     ?

8.    .
A, B, C, D  .

9.   /  . 
     .
(a) Radula (b) Parapodia
(c) Comb plates (d) Calcareous ossicles

10. ,      .

11.  . ( )

Granulocytes Hints
(A) – Monocytes
Neutrophil ................... Basophil
– Eosinophil
Function Percentage

– 20 – 25%
(B) – Phagocytic
60 – 65% 2 – 3% ...................
– Inflammatory response

Allergic – 0.5 – 1%
(C) (D)
................... response ...................

FY-326 17 P.T.O.

12. (a) In human some ribs are bicephalic. Why ?
(b) Write the different components of Rib cage.

13. Observe the given figure and answer the questions.

(a) Label A and B.
(b) Differentiate cortical and juxtamedullary nephrons.

14. Name the following :

(a) hypoglycemic hormone

(b) hypercalcemic hormone

(c) emergency hormone

(d) antidiuretic hormone

15. (a) Draw the structure of
(i) Glycerol
(ii) Serine
(b) Name the given
(iii) Most abundant protein in animal world
(iv) Two aromatic amino acids

FY-326 18

12. (a)     .  ?
(b)      .

13.     .

(a) A, B  .
(b)      
 .

14.   .
(a) hypoglycemic hormone

(b) hypercalcemic hormone

(c) emergency hormone

(d) antidiuretic hormone

15. (a) (i) Glycerol (ii) Serine
  
(b)   .
(iii)     .
(iv)    .

FY-326 19 P.T.O.

16. (a) Enzymes are divided into six classes. Write any two classes.

(b) What are cofactors ? What happens to enzyme activity if cofactor is removed

from enzyme ?

III. Answer any 3 questions from 17 to 20. Each correct answer carries 3 scores. (3  3 = 9)

17. Observe the given figures A and B, answer the questions.

(a) Identify body forms A and B.

(b) How will you differentiate them ?

(c) What is metagenesis ?

18. (a) Write the functions of

(i) Renin

(ii) ANF (Atrial natriuretic factor)

(b) Explain the role of lungs and liver in elimination of excretory wastes.

FY-326 20

16. (a)    .  
 .

(b)   ?   
      ?

III. 17  20    3  .

  3  . (3  3 = 9)

17.   A, B    .

(a) A, B    .

(b)      ?

(c)    ?

18. (a)   .
(i) Renin

(ii) ANF (Atrial natriuretic factor)

(b)     
 .
FY-326 21 P.T.O.

19. Observe the given figure and answer the questions.

(a) Label A, B, C and D.

(b) Write the location of

(i) Unipolar neuron

(ii) Bipolar neuron

20. Differentiate

(a) Inspiratory reserve volume and expiratory reserve volume

(b) Residual volume and functional residual capacity

(c) Expiratory capacity and inspiratory capacity

____________

FY-326 22

19.     .

(a) A, B, C, D  .

(b) (i)  

(ii)      .

20.  .

(a) Inspiratory reserve volume and expiratory reserve volume

(b) Residual volume and functional residual capacity

(c) Expiratory capacity and inspiratory capacity

____________

FY-326 23 P.T.O.

FY-326 24