(NB!!! Click on the down arrow to see the other options).

1.) A solution which causes cells immerged in it to shrink is described as being

Catatonic Hypotonic Isotonic Mnemonic Hypertonic

2) The water potential of a turgid cell will be

0 Kpa Equal to the osmotic potential about -100 Kpa Lower than its osmotic potential Impossible to say

Which of these factors does not affect transpiration rate ?

oxygen concentration of the atmosphere Water concentration of the atmosphere Light intensity Temperature of the atmosphere Wind

4) Wilting of a young plant is caused by changes in

the humidity of the air the turgidity of the cells the width of the stomata the osmotic potential of the cells the light intensity

5)Water passes across the cortex of a root from the root hair to the xylem vessels as a result of the presence of

a casparian strip excessive water in the soil a turgor pressure gradient an osmotic potential gradient a water potential gradient

6)If a young seedling is taken from a box and planted out on a hot day it will die unless it is shaded and carefully looked after. The cause of this is most likely because the

light is too strong soil is too hot root hair cells are damaged soil is not deep enough stem has been damaged

7)If the osmotic potential of a plant is -1200 Kpa and its turgor pressure is 400 Kpa, what will be its water potential ?

800 Kpa - 1600 Kpa - 800 Kpa 1600 Kpa None of these Answers

8)If the cell refereed to in question 7 was placed in a solution with water potential of -1400, in which direction would the water molecules move by osmosis ?

Into the cell Out of the cell Both in and out but mostly out Both in and out but mostly in There would be no water movement

9) If this same cell was now put in pure water, what would its osmotic potential be?

0 Kpa -800 Kpa -1200 Kpa -1600 Kpa 400 Kpa

10) The following graph shows the rates of water absorption and transpiration that occurred in a sunflower plant during a 24 hour period.

From this evidence it is true to say that in

light, absorbtion rate always exceeds transpiration rate dark, absorbtion rate always exceeds transpiration rate light, transpiration rate always exceeds absorbtion rate dark, transpiration rate always exceeds absorbtion rate in total, transpiration rate always exceeds absorbtion rate

11) Which of the following statements is NOT TRUE?

The greatest rate of transpiration normally occurs at 14:00 hours The rate of water movement in the branches is not related to that in the trunk The leaves provide the driving force for the upward movement of water A larger amount of water passes through the branches than the trunk The trunk cannot supply the branches with enough water

12)Two water lily and 2 oak tree leaves are arranged on a pivot ( as seen in the diagram below) so that they balance exactly

What will occur to the balance of the pivot after a short time?

4 will move up and 1 will move down 4 will move up and 2 will move down 3 will move up and 1 will move down 3 will move up and 1 will move down the balance will stay in the same position as it was set up in