Absorption by Roots & Ascent of Sap

Board Exam. (2002 to 2012) Questions & Answers2002

Q.1.Choose the correct answer for the following :

Marine fish when thrown under tap water bursts because of :

(a) Endosmosis (b) Exosmosis

(c) Diffusion (d) Plasmolysis

Q. 2 Name the following :

Condition of a cell placed in hypotonic solution.

Q. 3 Define the term diffusion.

Q. 4 The figure given below is a diagrammatic representation of a part of the cross of the

root in the root hair zone. Study the same and then answer the questions that follows :

(i) Name the parts indicated by guidelines '1' to '5'.

(ii) Is the root hair cell unicellular or multi-cellular ?

(iii) Draw a labelled diagram of the root hair cell as it would appear if some fertilizer

is added to the soil close to it.

(iv) Name the process responsible for the entry of water molecules from the soil into

Al and then A2.

(v) What pressure is responsible for the movement of water in the direction

indicated by arrows ?

(vi) How is this pressure set up ?

(vii) 2003

Q.5.Name the following :

The pressure which is resonsible for the movement of water molecules across the cortical

cells of the root.

Q.6.Give reason : Wilted lettuce leaves if kept in cold water become crisp. [2010]

2004

Q. 7 Rewrite the terms in the correct order so as to be in logical sequence.

Cortical cell, Root hair, Xylem, Water, Veins. [2006]

Q. 8 Give biological reasons for the following :

(i) Salt and Sugar are used in preserving food.

(ii) Some plants show wilting of their leaves during mid day even when the soil is well

watered.

(iii) On sprinkling common salt on grass growing in a lawn, the grass is killed.

2005

Q.9 Explain the term plasmolysis. Give one application of this phenomenon in our daily lives.Ans. Plasmolysis : The shrinkage of the protoplasm from the cell wall under the action of some

hypertonic solution which is more concentrated than the cell sap is known as plasmolysis.By addding salt in pickles, the growth and multiplication of bacteria can be prevented due to plasmolysis

Q.10 Given below is the diagrammatic representation of the transverse section of a part of a plant. Study the same and answer the questions that follow

(i) Name the part of the plant that is shown?(ii)Label the parts 1 to 6, indicated in the diagram.(iii)Write the functions of parts 3 and 5.

Marine fish bursts when thrown under tap water.

2006

Q.12 Define Hypotonic solution.

2007

Q.13 Name the following :

(i) A solution whose concentration is greater than that of the cell sap.

(ii) Transports water from the soil to other parts of the plant.

Q.14. Explain the term Osmosis.

Q.15. Identify the incorrect term and replace it with the correct term.

Soil water Root hair Cell of cortex Endodermis Xylem

Q. 16 Give reasons : Plants begin to die when excess of soluble fertilizer are added to the

soil.

2008

Q.17. 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

box. You may use the term only once.

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.

Q. 18 Given below are sets of 5 terms each. Without changing the first term, rearrange the

remaining four, so as to be in logical sequence as per the directions given in brackets for

each. One has been done for you as an example.

Example : Pathogen, active immunity, produces antibodies, lymphocytes, antigen.

(defence mechanism of the body).

Soil water, xylem, cortex, endodermis, root hair (conduction of water).

Q. 19 Given below is an example of a particular structure and its special functional

activity.

e.g. Glomerules and ultra filtration. On a similar pattern complete : phloem and _________

Q. 20 Given below is an incomplete explanation of certain biological process/ term where a

key word has been left out. Rewrite the completed explanation by inserting the key word in

the space indicated by ‘^’. Osmosis is the movement of water molecules from its region of

high concentration to its region of low concentration through a '^' membrane.

Q. 21 Give the technical / biological term for the following :

The process of mixing of two different substances / molecules:

Q. 22 Differentiate, between the following on the basis of what, is given in brackets.

Wall pressure and Turgor pressure (Explain briefly).

Q. 23 Given below are diagrams of plant cells as seen under the microscope after having

been placed in two different solutions.

(i) What is the technical term for the condition

of :

1. Cell A

2. Cell B ?

(ii) From the solutions given in brackets (water,

strong sugar solution, 1% 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 responsible for the movement of water from the root hair cell to

the xylem of the root. How is it set up ?

(v) Name the pressure that helps in the movement of water up the xylem of the root.

Q.24. Account for the following briefly :

Herbaceous plants growing in well watered soils are found to wilt on a hot day..

Q.25 Differentiate between tonoplast and plasma membrane. (Location).

2009

Q.26 Give the specific function of the following structure found in the body of

plants/animals : Xylem.

Q.27 Identify and name the following process / term from the statement given below :

Movement of molecules from a region of high concentration to a region of low

concentration.

Q.28 Explain the following terms : Root pressure.

2010

Q.29 Given below are five sets of five terms each. In each case, rewrite the terms in logical

sequence as directed at the end of each statement. One has been done for you as an

example. Example : Anaphase, Telophase, Prophase, Metaphase, Interphase

(sequential order of Karyokinesis)

Answer : Interphase, Prophase, Metaphase, Anaphase, Telophase.

Cortical cells, root hair, soil, water, endodermis, xylem. (entry of Water into the plant from

the soil)

Q.30 Given below is the diagram of an apparatus

set up to study a very important physiological

process:

(i) Name the process being studied.

(ii) Explain the process.

(iii) What change would you observe in the

thistle funnel containing sugar solution after

about 10 minutes?

(iv) Is sugar solution hypertonic or hypotonic?

(v) Name the part of the plant cell which is

represented by the sugar solution.

(vi) Explain why much salt is added to pickles.

Q.31. Explain the following term : Turgidity.

2011

Q.32 Rewrite and complete the following sentences by inerting the correct word in the

space indicated :

(i) Wooden doors swell up in rainy season due to ____________

(ii) ___________ is the phenomenon of contraction of the cytoplasm from the cell wall.

Q.33 Give reasons :

Potato cubes when placed in water become firm and

increase in size.

Q.34. The diagram given aside represents a layer of

epidermal cells showing a fully grown root hair. Study

the diagram and answer the questions that follows:

(i) Name the parts labeled A, B, C and D.

(ii) The root hair cell is in a turgid state. Name and

explain the process that caused this state.

(iii) Mention one distinct difference between the parts labelled A nd B.

(iv) Draw a diagram of the above root hair cell as it would appear when a concentrated

solution of fertilizers is added near it.

2012

Q.35 Name the phenomenon by which living or dead plant cell absorb water by surface

attraction.

Q.36. Give the biological / technical term A membrane which allows the passage of

molecules selectively.

Q.37. Given below is the diagram of a cell as seen under the microscope after having been

placed in a solution :

(i) What is the technical term used for the

state/condition of the cell given above ?

(ii) Give the technical term for the solution in

which the cell was placed.

(iii) Name the parts numbered 1 to 4.

(iv) Is the cell given above a plant cell or an animal

cell ? Give two reasons in support of your answer

as evident from the diagram.

(v) What would you do to bring this cell back to its

original condition ?

Q.38. Briefly explain Osmosis.