Movement of Substances

MOVEMENT OF SUBSTANCES

Student Name ______

1.

1.What process is responsible for the uptake of minerals in a plant? ______

2.Name the process responsible for the entry of water into a plant. ______

3.What is osmosis? ______

4.Water enters the outermost cells of the root by osmosis. What does this tell you about the cell sap of these outermost cells? ______

5.Describe how minerals such as nitrates enter the root of a plant from the soil. ______

6.Osmosis has been described as a special case of diffusion. Explain why.______
______

7.What is meant by osmoregulation? ______
______

8.Where precisely does water enter a plant? ______

9.In which tissue does water ascend through the plant? ______

2. Explain each of these terms:

1 Diffusion ______

3 Visking tubing ______

4 Passive process ______

5 Semi-permeable ______

6 Osmoregulation ______

7 Turgid ______

8 Plasmolysed ______

9 Food preservation ______

10 Dehydrated ______

11 Active transport ______

3. Complete the following:
Molecules move from a ______concentration to a ______concentration by

______. Osmosis is the movement of ______molecules from an area where they are in a ______concentration to where they are in a ______concentration, through a ______–permeable membrane. When plant cells take up water by osmosis they become ______.These cells help ______parts of a plant like the stem. If plant cells lose water, the stem loses support and it______. If plant cells lose a lot of water, the cell ______peels away from the cell ______and the cell is said to be ______

4. The diagram shows the apparatus for an experiment

using Visking tubing. The tubing is flexible and
allows very small molecules to pass through it but
not larger ones.

(a) Make a similar drawing to show the
appearance of the tubing after one hour.
(b) Explain how this change occurred. ______

(c) What is the name of the process that causes this change? ______
(d) Explain why half a cucumber becomes soft if left lying on a kitchen shelf for a few days, but becomes
turgid again if its cut end is placed in water.
______
______

5. (a) Red blood cells have a 1% salt concentration inside them. What would happen to the red blood cells if
they were placed in a beaker containing the following solution:
(i) pure water ______
(ii) a 1% salt solution ______
(iii) a 5% salt solution? ______
(b) A plant cell also has a salt concentration of 1% in its cytoplasm and central vacuole. Say what
differences there would be when these cells are placed in each of the three solutions mentioned in (a).
(i) pure water ______
(ii) a 1% salt solution ______
(iii) a 5% salt solution? ______

(c) An amoeba living in a freshwater pond contains a contractile vacuole.
State the function of this structure ______
Explain why its presence is necessary ______

Why does an amoeba living in seawater not possess a contractile vacuole?
______

6. Three strips of plant epidermal cells were placed on

microscope slides. Each was covered by one drop
of a solution, as shown in the table.

STRIP 1 STRISTRIP 3

The diagrams below show the appearance of some
of the cells after one hour.
Two of the strips had cells as shown in diagram A.
One strip had cells as shown in diagram B.

(a) (i) Which one of the strips (1, 2 or 3) would have cells
that look like Diagram B?______
(ii) Explain what happens to a cell to make it look like
Diagram B.______
(b) Which one of the following would be found at the position labelled X in Diagram B?
Water alone, Sugar solution Cell sap, Air, Cytoplasm ______
(c) What would happen to a leaf if most of its cells became like Diagram B? ______