1. You are provided with specimen labeled A. Obtain a cube measuring 1cm by 1cm from the specimen.

(a) Crush the cube using mortar and pestle, place the crushed parts in measuring cylinder, add 2 ml of hydrogen peroxide and quickly determine the volume of foam after 20 seconds and fill the table below. (1 mark)

SpecimenVolume of foam
Crushed cube A 

Explain why the reaction in (a) above occurs in living cells.                                                         (2 marks)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

………………………………………………………………………………………………………………

(b) You are provided with a solution labeled B, unboiled C1 and boiled C2. Place 2ml of the solution B into two test tubes and carry out a food test using the reagents provided. Record your observation in the table below.                                                                                                       (2 marks)

FOOD SUBSTANCEPROCEDUREOBSERVATIONCONCLUSION
                    
                

Place 2ml of solution B into four test tubes labeled F, G, H and K. Carry out the following steps.

(i) To test tube labeled F and its contents add 3ml solution C1 and 3 ml distilled water.

(ii) To test tube labeled G and its contents, add 3ml solution C1 and 3 ml dilute hydrochloric acid.

(iii) To test tube labeled H and its contents, add 3 ml solution C 1 and 3 ml sodium hydroxide solution.

(iv) To test tube labeled K and its contents, add 3 ml solution C2.

 (v) Place the test tubes in a water bath at 37 C for 20 minutes.

(vi) Carry out a Benedict’s test and fill the table below.                                                  (4 marks)       

Test tubePROCEDUREOBSERVATIONCONCLUSION
F           
G             
H             
K               

(a) Account for the observation in:

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(i) Test tube G.                                                                                                                               (2 marks)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

(ii) Test tube H.                                                                                                                               (1 mark)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

(iii) Test tube K.                                                                                                                             (2 marks)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

2. Use the illustration below to answer questions

(a) Identify the organism from which the cell labelled B was obtained from while giving a reason.

(ii) B.                                                                                                                                               (1 mark)

…………………………………………………………………………………………………………….

Reason.                                                                                                                                           (1 mark)

……………………………………………………………………………………………………………

(b) Give the functions of the parts labeled:

(i) R.                                                                                                                                                (1 mark)

……………………………………………………………………………………………………………..

(ii) S.                                                                                                                                                (1 mark)

……………………………………………………………………………………………………………..

(b) Name the parts labeled:

(iii) Q.                                                                                                                                               (1 mark)

……………………………………………………………………………………………………………..

(iii) P.                                                                                                                                               (1 mark)

……………………………………………………………………………………………………………..

(iv) K.                                                                                                                                               (1 mark)

……………………………………………………………………………………………………………..

(d)  Calculate the actual length of cell A in micrometers if its magnification Is X1000 000.Use the points marked L and X.                                                                                                                             (3 marks)

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(e) Explain why cell A and B are believed to have a common ancestry.                                       (2 marks)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

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3. Use the photographs below to answer questions

(a) (i) Name  the type of flowers shown in A1 and A2.                                                               

(i) A1.                                                                                                                                               (1 mark)

……………………………………………………………………………………………………………..

(ii) A2                                                                                                                                               (1 mark)

……………………………………………………………………………………………………………..

(ii) Describe the feature in flowering plants depicted in (a)(i) above.                                           (1 mark)

…………………………………………………………………………………………………………….

 (iii) Explain how flower labeled A1 is modified for pollination.                                                     1 mark)

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

(b) Give the functions of the parts labeled p, r and s in specimen labeled B.

(i) p.                                                                                                                                                (1 mark)

……………………………………………………………………………………………………………..

(ii) r.                                                                                                                                                (1 mark)

……………………………………………………………………………………………………………..

(iii) s.                                                                                                                                               (1 mark)

………………………………………………………………………………………………………………

 (c) State the structural descriptions of flower B.                                                                            (2marks)

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(d) Explain what would happen to the following parts after pollination.

(ii) t.                                                                                                                                                (1 mark)

……………………………………………………………………………………………………………..

(iii) u.                                                                                                                                               (1 mark)

………………………………………………………………………………………………………………

(e) You are provided with a specimen labeled K in a petri dish, observe the specimen using a hand lens and answer questions that follow.

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(i) Make well labeled diagram to show the reproductive structure of the organism.                     (3 marks)

(ii) Give the type of asexual reproduction exhibited by the organism.                                            (1 mark)

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