(a) Effect of temperature on enzymes ;
(b) So that contents of the tubes will have attained the temperature of the waterbath.
(c) A - Would turn blue black
B - Would turn brown / colour of iodine remained
C - Would turn blue black
(d) A - Very low temperature which inactivated enzyme / ptyalin / salivary amylase thus no digestion of starch.
B - Suitable temperature / favourable temperature / optimum / best temperature for activity of enzyme /salivary /amylase / ptyalin thus starch digested.
C - Temperature high / above optimum thus denaturing enzyme thus no digestion of starch.
sharon kalunda answered the question on March 21, 2019 at 14:12
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Show your working.
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(a)...(Solved)
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