(a)Describe briefly the process involved in the conversion of food to chyme in the stomach of a mammal.                                                                                                          
(b)Complete the table below by stating one enzyme, digestive juice, food acted upon and
end-product in the corresponding spaces.

(c) Describe an experiment to show that carbon dioxide is necessary for photosynthesis.

(a)  Explain briefly the following terms:

1. ecosystem;
2. abiotic environment.                                                         

(b)  List three ecological factors each which are specific to:

1. aquatic habitats;
2. terrestrial habitats.                                                           

(c)  State briefly the relationship between green grass and a rabbit in a given habitat.
(d)  Draw a typical pyramid of energy using four feeding levels.  

(a)(i)  State Mendel’s laws of inheritance.                                       

(ii) State five applications of genetics in medicine.                         

(iii) State three disadvantages of inbreeding.                                 

(b)(i) What is evolution?                                       
(ii) Distinguish between convergent evolution and divergent evolution.     

(a)   State five processes involved in the water cycle.                         
(b)   Name one instrument used for measuring each of the following physical factors:

1. pH;
2. light intensity;
3. turbidity;
4. temperature.                                                        

(c)  Explain briefly the contributions of the following scientists to the formulation of the cell theory:

1. Robert Hooke;                                                       
2. Theodore Schwann.                                                   

(d) What is meant by each of the following terms:

1. Nastism                                                     
2. Taxism                                                       

(e) Make a diagram, 6 cm – 8 cm long of the human tongue illustrating the four areas of taste.
(f)(i)   List four ways through which microorganisms enter the human body.                    
(ii)   State three harmful effects of microorganisms to humans.                             

Diagrams A, B and C are illustrations of different types of teeth in humans. Diagram D is a representation of the arrangement of teeth in the lower jaw of a human.

Study them and answer questions  (a) to (f).
(a) (i) Name the type of teeth in diagrams A, B, and C.                                   

(ii) Which of the teeth would be found in positions I, II and IV?             

(iii)State one function each of the teeth illustrated in diagrams A, B and C.         

(iv) State one reason each for the answers in (a) (iii).                             

(b)If the tooth labeled B is decayed, list two factors that may be responsible.                 
(c)What is the total number of each of the teeth labeled A, B and C in the dentition of an adult human?                                            
(d)Which of the teeth would be absent in a rabbit?                                                          
(e)(i)  Name the tooth that would be found in position III of diagram D.      
(ii)  In which of the parts labeled I, II, III and IV would a tooth not be found in an infant?                       
(f)  State five ways of caring for the teeth in humans.