TRANSPORT IN PLANTS FORM 2 BIOLOGY EXERCISE TERM 1

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  1. How are sieve tube elements adapted to their function.[4m]
  2. Name the polysaccharides found in the following structures:[2m]   
    1. Exoskeleton
    2. Xylem vessels
  3. State three forces that maintain transpiration stream. [3m]      
  4. Name the tissue that is removed when the bark of a dicotyledonous plant is ringed.[1m]   
  5. What is the destination of materials translocated in plants.[2m]    
  6. An experiment was set-up as shown below to investigate a certain plant process:                                                              
    1. What process was being investigated above?[1m]
    2. With a reason in each case what observation was made if;
           i.      The experiment was left in strong wind for one hour?[1m]
          ii.      All the leaves were removed from the plant? [1m]                                        
  1. The diagrams below show two conducting elements of the xylem tissue. 

a.       Identify each of them A and B[2m]
b.      State two functions of the xylem vessels.[2m]
c.       What is deposited on the cellulose side walls of both A and B able to prevent collapsing?[2m]
d.      What property makes B to be more efficient in function than A?[1m]
e.       What makes the walls of both A and B impermeable to water and solutes?[1m]
f.       What is the significance of xylem vessels being dead?[1m]  
g.      On diagram name the structure represented by circles and state its function.[2m]
  1. Explain why the rate of transpiration is reduced when humidity is high.[2m] 
  1. The diagram shows a section through a plant organ. 
a.       Name the class of the plant from which the section was obtained belong.[1m]       
b.      Give a reason for your answer in (a) above.[1m]
c.       How is the part labelled C adapted to its functions?[3m]                                         
  1. State two roles of transpiration to a plant.[2m]         
  2. Uptake of water by plants is not affected by metabolic poisons. Explain.[2m]
  3. Distinguish between guttation and transpiration. [1m]                                                         
  4. Explain how the following adaptation reduce transpiration in xerophytes.[2m]
          i.     Sunken stomata                               ii.      Thick waxy cuticle 
  1. The diagram below shows the traverse section of a young stem.
                                     
a.       Name the parts labelled A, B and D[3m]
b.      What are the functions of the structures labelled A, B and C            [3m]
c.       Name two types of cells found in the parts labelled D. [2m]
d.      Name the tissue labelled E and state its function. [2m]
e.       List three differences between the section above and the one that would be obtained from the root of the same plant.[3m] 
  1. The figure below represents a diagram of a potometer. 
        
a.       What is the potometer used for? 
b.      State the precautions which should be taken when setting up a potometer.
c.       Explain what you will expect if set up was placed under the following environmental conditions;
              i.      Dark room.[1m]
             ii.      Leafy shoot enclosed in polythene bag. [1m]
iii.      In a current of air created by a fan. [1m]

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