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(a) Define crop improvement. [2 marks] (b) Copy and complet the table below based on ...

(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).
TC Tc tC tc
TC TTCC
Tc Ttcc
tC ttCc
tc ttcC



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]
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    Correct Answer: Option n
    Explanation:
    (a) Definition of crop improvement: This is the science (ii) that deals with the development of new crop varieties with superior quality and quantity.
    (b)
    TC Tc tC tc
    TC (TTCC) TTCc TtCC TtCc
    Tc TTcC (TTcc) TtcC Ttcc
    tC tTCC tTCc ttCC ttCc
    tc tTcC tTcc (ttcC) (ttcc)



    (c) Tall Coloured: TTCC, TTCc, TtCC, TtCc, TTcC, TtcC, tTCC, tTCc, tTcC = 9
    Tall white: TTcc, Ttcc, tTcc, = 3
    Dwarf Coloured: ttCC, ttCc, ttcC = 3
    Dwarf white: ttcc = 1 ,.
    Calculation of percentage of plants that are:
    Tall Coloured = 9/16 x 100 = 56.25%
    (ii) Tall White = 3/16 x 100 = 18.75%
    (iii) Dwarf Coloured = 3/16 x 100 = 18.75%
    (iv) Dwarf White = 1/16 x 100 = 6.25% %
    Total = 100.00%

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