K.C.S.E Biology Q & A - MODEL 2015PP1QN09

K.C.S.E Biology Q & A - MODEL 2015PP1QN09

The diagram below shows an experimental set up to investigate a certain physiological process in plants.

​(a) State the aim of the experiment. 
(b) State the role of the following in the experiment:
(i) potassium hydroxide; 
(ii) aluminum foil. 
(c) Account for the expected colour change in tube F.

answers

​(a) To show that carbon (TV) oxide is produced during respiration in plants; 
(b) (i) Absorb carbon (IV) oxide from the (incoming) air;
(ii) Exclude light / to prevent photosynthesis; 
(c) No colour change in tube F / no observable colour change.
Carbon (IV) oxide removed/absorbed from air by potassium hydroxide.