K.C.S.E Biology Q & A - MODEL 2002PP1QN18

K.C.S.E Biology Q & A - MODEL 2002PP1QN18

Two person X and Y drunk volumes of concentrated solution of glucose. The amount of glucose in their food was determined at intervals. The results are shown in the table below:

​a) On the grid provided, plot graphs of glucose level in blood against time on the same axes.
b) What was the concentration of glucose in the blood of X and Y at the 20th minute?
X = 120 + -3)
Y = 140 +-3)
c) Suggest why the glucose level in person X stopped rising after 30 minutes while it continued rising in person Y.
d) Account for the decrease in glucose level in person X after 30 minutes and person Y after 60 minutes (3 minutes)
e) Name the compound that stores energy released during oxidation of glucose.
f) Explain what happens to excess amino acids and development of plants.

answers

(a) – For exchanged axis award maximum 3 marks for points x identity
The scale must however be correct. For graphs on separate axis mark both and award the highest mark.
(a) Axis = 2
(b) Scale = 1
(c) ( plotting) = 1
(d) curves) = 1
(b) X = 120 + -3)
      Y = 140 + -3
(c) Person X is capable of regulating glucose while person y is likely to be  diabetic.
   X – Insulin
(d) X insulin released, excess glucose is converted into glycogen ( in liver) must be mentioned if insulin is not mentioned
  Y Insulin not released, thus the decline is due to glucose being  released in urine.
(e) A.T.P / Adenosine triphosphate
(f) Deaminated; resulting in formation  of  ammonia
Ammonia  combines with CO2 to form urea ( and H20); Urea is passed out in Urine carbohydrate group is oxidized/ stored as glycogen