BIOLOGY PAPER 3 - KCSE 2019 MASENO MOCK EXAMINATION

QUESTIONS

1. You are provided with a substances labeled N,P,Q,R,S,V and W. N is Benedict's solution P is dilute hydrochloric acid, Q is sodium hydrogen carbonate solution, R is 10% sodium hydroxide solution, Suspensions V and w are test solutions
   1. Using the reagents provided, test for the food substances in the suspension. In the table below, record the food tested, Procedures, observations conclusions.(10mks).
   2. Name one enzyme that may be required to digest suspension W in the alimentary canal in human beings. State the organ from which the enzyme is produced.(2 marks)
   3. State the role of the following in the experiment.
      1. Substance Q (1 mark)
      2. Substance P (1mark)
2.  
   1. You are provided with specimens labeled W, X, Y and Z which are of plant origin. Using the festures in the order below, construct adichotomous key to identify the specimens.
      Simple or compound leaves
      Leaf venation
      Leaf margin:(6marks)
   2.  
      1. Open the flower of specimen X. Draw the pistil and on it label the structure that receives pollen grains.(2marks)
      2. How is the structure labeled in (b) above adapted to perform its function. (1marks)
   3. Using your fingers, strongly squeeze the stem of specimen W.
      1. Record your observations(1mark)
      2. From the observations, explain how the specimen is adapted to its habitat. (1mark)
   4.  
      1. Give one observable feature that adapt specimen Z to its habitat
      2. State how the feature adapt the specimen for survival in its habitat (1 mark)
         
         
3.  
   1. with three reasons, state the class to which specimen T and X belong (4 marks)
   2. How are the external features of specimen X adapted to locomotion?
   3. At what stage of development is spegimen R in the life cycle of specimen T? (1 mark)
   4. Give two reasons for your answer.(2 marks) 
   5. state two biological advantages of the above stage of development in the life cycle of specimen T.
   6. Name the stage of development represented by letter S