(a) Define the term soil. [2 marks]

(b)(i) List the four components of soil. [2 marks] (ii) State the percentage of each component by volume. [2 marks]

(c) Describe the process involved in making compost using the pit method under the following headings: (i) materials; [2 marks](i ) preparation; [6 marks] (iii) storage [2 marks] 

(a) Define soil erosion. [2 marks]

(b) List four factors that influence nutrient availability in the soil. [4 marks]

(c) Explain two roles of each of the following factors in soil formation: (i) climate; (ii) living organisms; (iii) topography. [6 marks]

(d) State four problems associated with overhead irrigation [4 marks] 

 (a)(i) Define crop rotation. [2 marks] (ii) Design a four-year crop rotation system using yam, cassava, maize and groundnut. [8 marks]

(b) State four reasons why weeds are difficult to control. [4 marks]

(c) Mention 'two effects of diseases on crop production [2 marks] 

(a) Define crop improvement. [2 marks]

(b) Copy and complet the table below based on Mendel's Law of Indepen-dent Assortment of Genes (Dihybrid inheritance).

Use the following information: T = Tall; C = Coloured; t = Dwarf; c = White. (Where T and C are dominant character; while t and c are recessive TC TTCC characters) [6 marks]

(c) Calculate the percentage of plants in (b) above that are: (i) Tall coloured; (ii) Tall white; (iii) Dwarf coloured; (iv) Dwarf Tc Ttcc white [8 marks] 

(a) Name four breeds of rabbits. [2 marks]

(b) Give two reasons why oestrus detection is important in farm animals. [2 marks]

(c) State four functions of each of the following hormones in farm animals. (i) androgen; (ii) oestrogen. [8 marks]

(d)(i) List two viral diseases of poultry. (ii) List two ecto-parasites of poultry [4 marks]