A group of students set up an experiment to investigate a certain physiological process. The set up was as shown in the diagram below.

​A group of students set up an experiment to investigate a certain physiological process. The set up 
was as shown in the diagram below.

​(a) What physiological process was being investigated? (1mk)

​Osmosis

​(b) (i) State two major observation that was made after some time. (2mks)

• Distilled in the Irish potato would reduce in level; (1mk)
• Level of concentrated salt solution would increase in the Petri dish(2mks)

​(ii) Account for the above observation in b (i) above. (4mks)

​Concentrated salt solution in the Petri-dish has higher osmotic pressure than the cells of the Irish potato; these cells lost water to the salt solution by osmosis; these cells become more concentrated and drew water from the neighbouring cells; this process continued until the cells in contact with water in the potato drew it up.       (4mks)

​(c) State the significance of the biological process involved in the experiment. (1mk)

• Support in herbaceous plants
• Absorption of water
• Opening and closing of stomata
• Movement and water between plants
• Feeding in sectivorous plants
• Folding of leaves of mimosa pudica when touched