OUR OWN ENGLISH HIGH SCHOOL, ABU DHABIGrade 9

The Fundamental Units Of LifeConcept: Osmosis

Answer this worksheet as home work and submit it on the second biology period of the week 21st to 25th April.

KNOWLEDGE / UNDERSTANDING

I. The following paragraph is related to absorption of water from the soil. Copy and complete the following paragraph by selecting the correct word from those given in the bracket. You may use the term only once. [K]

(Exosmosis, Hypertonic, Osmosis, Isotonic, Hypotonic, Cortical, Endosmosis)

Water enters the root hair from the soil by the process of _______ . This is because the solution in the soil is _______ whereas the cell sap in the root hair cell is _______. The water then passes through the _______ cells by cell to cell _______ and reaches the xylem of the root.

II. Fill in the blanks for the following questions.[ K]

1) _____________ is the movement of particles from an area of higher concentration to an area of lower concentration.

2) ______________ allows some materials to pass through it but keeps other materials out.

3) _______________ is the diffusion of water molecules through a selectively permeable membrane.

4) _______________ happens when water particles move from a place where their concentration is higher to a cell where their concentration is lower.

APPLICATION

III. Given below are diagrams of plant cells as seen under the microscope after having been placed in two different solutions: [A]

i. What is the technical term for the condition of: l. Cell A 2. Cell B? ii. From the solutions given in brackets (water, saturated sugar solution, dilute salt solution) name the solution into which: 1.Cell A 2. Cell B was placed before being viewed under the

microscope. iii. Under what conditions in the soil will the root hair cell resemble: 1.Cell A 2. Cell B? iv. Name the pressure that helps in the movement of water up the xylem of the root.

COMMUNICATION

IV. Use the following diagram to answer the questions given below [C]

A B C

Explain the process of Osmosis taking place in the cells A, B, and C

HOTS

V. Match each Term on the left with the best Descriptor on the right. Each Descriptor may be used only once [H]

Term Descriptora. Concentration a. Moves oxygen into cells

b. Diffusion

b.c. Equal amount of water inside a

cell as outside c.Allows some substances through

d. More water outside a cell than inside

d.e. Selectively permeable

membrane e.Moves water into and out of cells

f. Osmosis f. Amount of a substance in a certain place

VI ) Explain why a plant wilts when given too much fertilizer.[H]

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