Absorption by Roots The Processes Involved ICSE Class 10 Biology Board Exam Questions

Students should refer to Absorption by Roots The Processes Involved ICSE Class 10 Biology Board Exam Questions provided below with solutions. These will help the students to understand the type of questions which have been asked in previous year examinations and the type of solutions which the student should give to get good marks. You should also refer to ICSE Class 10 Biology Sample papers for more practice

ICSE Class 10 Biology Absorption by Roots The Processes Involved Important Questions

Students should learn the important questions and answers given below for Chapter Absorption by Roots The Processes Involved in Biology for ICSE Class 10. These board questions are expected to come in the upcoming exams. Students of ICSE Class 10th should go through the Important questions and answers ICSE Class 10 Biology which will help them to get more marks in exams.

Absorption by Roots The Processes Involved ICSE Class 10 Biology Board Exam Questions

Absorption by Roots The Processes Involved ICSE Class 10 Biology

Question: Name the following :

a. Part of the root which absorbs water.

b. Cell organelle which contains the cell sap.

c. Movement of food from leaves to other parts.

d. The mineral needed for chlorophyll synthesis.

Question: State whether the following statements are ‘True’ or ‘False’.

a. Cell membrane is thin and freely permeable

b. Fixation of plant in the soil prevents soil erosion.

c. Water and carbon dioxide are raw materials for photosynthesis.

d. Root hairs are multicellular.

Question: Small potato cubes were placed in two containers A and B containing some liquid. After 24 hrs. when the cubes were examined, those placed in a were found to be firm and had enlarged by few millimeter. Those placed in B were soft and decreased is size. Use the above information and answer the questions that follow.

a. Account for the softeness and decrease in size of the potato cubes which were placed in the liquid in B.
Ans. The cells of potato cube in container B lose water due to exosmosis. Loss in water leads to flaccidity thus the cube turns soft. Loss in water limps the cell size thus cube decreases in size.

b. What can you say about the liquids in containers A and B ?
Ans. The liquid in container A is Hypotonic in nature. The liquid in container B is Hypertonic in nature.

c. Define the above mentioned process.
Ans. Osmosis is the movement of solvent molecules from a solution of their higher concentration to a solution of their lower concentration across a semi-permeable membrane.

d. Name the process being studied.
Ans. The process being studied is osmosis.

e. Account for the firmness and increase in size of the potato cubes which were placed in liquid A.
Ans. The cell of the potato cube gain water due to endosmosis. It gains water leading to turgidity which gives swelling and firmness. Gain in water causes firmness in cell size and thus the cube increases in size.

Question: Explain the fate of a human RBC when placed in different kinds of solutions.
Ans. A. When placed in isotonic solution the water entering the cell equals the water leaving it. Thus the cell size and shape remained unchanged.
B. When placed in hypotonic solution. The water enters the cell due to endosmosis. The cell slightly enlarges or even bursts.
C. When placed in hypertonic solution. The cell loses water due to exosmosis. The cell shrinks in size and loses shape (undergoes crenation).

Question: What are the uses of turgidity to the plant ?
Ans. (a) Turgidity gives rigidity to soft tissue especially the leaves.
(b) The opening and closing of stomata is regulated by the turgidity of the guard cells.
(c) Turgor pressure helps the radicle or plumule to push through hard surfaces.
(d) It is responsible for turgor movements.
(e) Turgor in root cells builds up root pressure which helps in upward rise of water in a stem.

Question: What are the main primary functions of a root ?
Ans. The main primary functions of a root are –
1. Anchorage : The extensive root system holds the plant firmly to the soil.
2. Absorption : The root hair absorbs water and minerals from the soil.
3. Conduction : The root conducts the absorbed substances through its tissue to reach the upper parts of a plant.

Question: The wooden doors of houses get jammed in rainy seasons. Say why ?
Ans. Wood is highly hydrophilic i.e., has strong affinity for water. The cellulose (wood) imbibes water from surroundings and swells up. Thus the doors get jammed inside the frames.

Question: What is the need of water for the plant, discuss ?
Ans. A Plant needs water for the following purposes :
1. Turgidity : When the vacuole is filled with water, it tends rigidity to plant part.
2. Translocation : Food prepared by leaves is transported in a solution form.
3. Transpiration : The water lost by transpiration causes cooling to the plant
4. Photosynthesis : A small amount of water is used up as raw material for manufacture of food.

Question: Salting of meat keeps it fresh for a long time.
Ans. The salt forms a hypertonic solution with the water in the meat. The bacteria that cause spoilage of food come to lie in this hypertonic solution and lose water by exosmosis and eventually get plasmolysed and killed. Thus meat remains fresh for a long time.

Question: Differentiate between diffusion and osmosis.
Ans.

Question: Give one example of diffusion in plants.
Ans. During respiration, CO₂ diffuses out through the stomata while O₂ from outside diffuse into the intercellular spaces of the leaf.

Question: Study the diagram given below and answer the questions that follows:
i) Explain the physiological process being studied.
ii) What will be observed in two test tubes A and B after 2 days ?
iii) Give a reason for your answer in (ii) above.
iv) What is the purpose of setting up test tube B?
v) Why is the surface of water in the test tubes covered with oil ?

Ans. i) The physiological process is that roots absorbs water is a plant.
ii) Test tube A : drop in water level
    Test tube B : level of water remains the same
iii) In test tube A, the roots are intact. They absorb water by osmosis, thus a drop in level is observed. In test tube B, there is no plant, thus there is no absorption of water. Therefore level of water remains the same.
iv) Test tube B acts as a ‘control’
v) The surface of water is covered with oil to prevent any loss of water by evaporation

Question: Differentiate between endosmosis and exosmosis.
Ans.

Question: Give example of turgor movements.
Ans. (a) T h e d r o o p i n g o f t h e l e a f l e t s o f Mimosa pudica plant when touched.
(b) Opening and closing of lids in insectivorous plants eg. Nepenthes.
(c) Folding and unfolding of leaves in Oxalis.

Question: What do you understand by ‘Osmotic pressure’ ?
Ans. The pressure by which the water molecules tend to cross the semi-permeable membrane is called OP. (It is equal to the pressure required to nullify osmosis).

Question: Salt and sugar are used as preservatives.
Ans. Extra solutes like salt and sugar when added to the food form a hypertonic solution. The bacteria that cause spoilage of food come to lie in this and get plasmolysed as they lose water due to exosmosis and get killed. Thus salt and sugar help to preserve food stuffs. 

Question: A well watered healthy potted plant is taken and the stem is cut close to the base. A glass tube is attached to the stem as shown. A small amount of water is put into the glass tube.
a. State what you would observe after a few hours.
b. Give an explanation for the observation.
c. Name the process responsible for above.
d. Define the process mentioned above.
e. What is the purpose of putting oil on the surface of water.

Ans. a. Water level in glass tube increases.
b. Due to root pressure, water can rise in the tube (or in the stem in natural condition) up to a certain height only. Loss of water through a cut stem is called bleeding.
c. Root pressure.
d. Root pressure is the pressure developed in the roots due to continued inward movement of water through cell to cell osmosis which helps in the ascent of cell sap upward through the stem.
e. To check rise of water and prevent evaporation of water.

Question: The diagram alongside represents an experimental setup to demonstrate a certain process. Study the same and answer the questions.

a. Name the process being demonstrated.
Ans. Osmosis.

b. What would you observe after 1 hour?
Ans. The level of solution in the stem of thistle funnel rises and the level of water in the beaker drops.

c. Define the process mentioned above.
Ans. It is the movement of solvent molecules from a solution of their higher concentration to a solution of their lower concentration across a semi-permeable membrane.

d. What control experiment can be set up for comparison?
Ans. A similar set up with water inside the thistle funnel will be a control.

e. Mention two advantages of the process to the plants.
Ans. 1. It helps in opening and closing of stomata.
2. It helps in absorption of water from soil by the root hairs.

f. Name any other material that can be used instead of cellophane paper?
Ans. Parchment paper / goat’s bladder / egg membrane.

Question: State the significance of imbibition to plant.
Ans. a. It helps in the uptake of water by the root hair
b. Imbibition pressure helps in the ascent of sap i.e., upward movement of water and dissolved salts.

Question: The diagram below is a part of the T.S. of root. Study the same and answer the questions that follow :

a. Name the parts indicated by guidelines 1 to 5.
b. Is the root hair unicellular or multi cellular ?
c. Name the process responsible for the entry of water molecules from the soil into A1 and then is to A2.
d. What pressure is responsible for the movement of water in the direction indicated by arrows ?
e. How is this pressure set up ?
Ans.

b. Unicellular
c. Endosmosis, Osmosis
d. Root pressure, Osmotic pressure
e. Root pressure is set up due to continued inward movement of water through cell to cell osmosis which helps in ascent of sap.

Question: What causes the leaflets of Mimosa pudica to drop on being touched.
Ans. The leaflets of this sensitive plants remain upright due to the turgidity of the cells of the pulvinus (swollen leaf base). The drooping of leaf of Mimosa pudica is brought about by the changes is the turgidity of the cells at the base of leaflets and pulvinus. Loss of turgor leads to drooping of entire leaf.

Question: Drawn below is a diagram of an onion peel cell placed in water. Study the diagram and answer the questions that follow :
a. Label the part 1 to 5.
Ans. 1. Cell wall
2. Plasma membrane
3. Cytoplasm
4. Vacuole
5. Nucleus

b. What is the condition of the cell ?
Ans. It is a turgid cell

c. What is the function of parts labeled 1 & 2 ?
Ans. Function :
Part 1: The cell wall exerts pressure on the cell content called wall pressure.
Part 2: Regulates the entry of certain solutes and ions.

Question: How is a root adapted for absorbing substances ?
Ans. A root is very well adapted to carry out the process of absorption in an efficient manner.
1. Enormous surface area : It is a profusely branching system which ends in large number of unicellular root hair through which substances enter.
2. Concentrated cell sap : The cell sap in the large vacuoles is concentrated, thus allowing for osmosis to occur and water from the soil enters inside.
3. Thin cell wall of root hair which allows free movement of water and minerals.
4. Thin semi-permeable cell membrane which allows water molecules to pass through but not large molecules of dissolved salts by osmosis.

Question: State applications of plasmolysis in daily life.
Ans. Plamolysis can be induced in living cells and has various applications –
(a) Salting of meat keeps it fresh for a long time.
(b) Weeds can be killed by sprinkling salt around their bases.
(c) Jams and pickles are preserved by adding excess sugar or salt.
(d) Sprinkling of salt around the mouth of leech can make it loosen its grip.
(e) Gargling with salt water helps to relieve throat infection.

Question: Diagram along side is a full grown root hair and two more in successive stages of growth. Study the diagram and answer the questions.

a. Is the root hair unicellular or multi-cellular ?
Ans. Unicellular

b. Label the parts marked 1 to 4.
Ans. 1. nucleus
2. cell wall
3. vacuole
4. cytoplasm

c. State two adaptations in a root hair for its function.
Ans. 1. A huge surface area.
2. Root hairs have thin walls.

d. What is the condition of the cell drawn in above answer.
Ans. Flaccid.

e. The above drawn root hair was immersed in a strong solution for few hours. Draw a neat diagram of the root hair at the end of few hours.

Ans.

Question: A woody stem was girdled by removing a ring of bark leaving the xylem intact A bulge develops above the girdle in a few weeks.
a. Account for the swelling in the bark above the ring.
b. Account for the shrinkage of the bark below the ring.
c. Name the tissue that distributes food in plants.
d. Name the tissue that distributes water in plants.
e. What is the fate of this plant ?

Ans. a. The swelling above the ring takes place due to accumulation of food because phloem has been removed from that part.
b. The shrinkage of the bark below the ring takes place due to the absence of food.
c. Phloem.
d. Xylem.
e. The food from the leaves is conducted downward through the phloem in the stem.

Question: On sprinkling common salt on grass growing in a lawn, the grass is killed.
Ans Common salt with little soil water forms a hypertonic solution. The cells of the root of grass lie is this solution. The cells lose water due to exosmosis and get flaccid and killed.

Question: What is the significance of osmosis ?
Ans. 1. It helps in the absorption of water by root hairs in the plants from the soil.
2. It regulates the opening and closing of stomata.
3. It allows the movement of water from one cell to another setting up an osmotic gradient thereby ensuring conduction of water and minerals.

Question: Discuss the role of absorbed minerals by the plant.
Ans. The root absorbs nitrogen, magnesium, potassium, phosphorus and calcium etc., in ionic form. Nitrogen : It is needed for protein synthesis Magnesium : It is needed for synthesis of chlorophyll. Calcium : It is needed to maintain semi-permeability of cell membrane

Question: The body of a marine fish often bursts when placed in tap water.
Ans. A marine fish is adapted to live in salt water (hypertonic) of the sea. It accumulates salts in its body to equalize osmotic pressure of internal and external medium. But when placed in tap water which is hypotonic, its cells gain water by endosmosis. Thus the fish burst when placed under tap water.

Question: If you uproot a plant from the soil, its leaves soon wilt.
Ans. When you uproot a plant from the soil, the roots are no more exposed to soil water and therefore the absorption stops. So, the leaves cells do not get water and soon all turn flaccid. This results in wilting of leaves.

Question: Draw a neat and labelled diagram of a root hair.
Ans.

Question: Select the appropriate term from the list provided below and complete the sentences by filling the blanks.

a. When RBC is placed in brine solution _____________ occurs.

b. __________ does not require an energy input to take place.

c. ___________ is energy requiring movement of ions through a membrane against the concentration gradient.

d. The movement of particles from a region of higher concentration to region of lower concentration is _____________

e. When potato cube is placed in water ____________ occurs.

Ans. Endosmosis

f. ___________ refers to the relative concentration of solutes of two solutions.

g. _________, __________ and other small molecules with no net charge diffuse across the cell membrane.

h. When solutions are __________ there is no net movement in either direction.

Q.I. Pick up the correct answer from the given choices :

1. Deplasmolysis in a cell occurs when it is placed in:
a. iostonic solution 
b. hypotonic solution
c. hypertonic solution
d. none of these

2. The cell increases in volume if the external solution is:
a. hypotonic
b. hypertonic
c. isotonic
d. conc. than cell sap

3. Transport of substances against the concentration gradient in a cell by using energy is:
a. Osmosis
b. diffusion
c. passive transport
d. active transport

4. Pressure exerted by cell contents on the cell wall is:
a. wall pressure 
b. turgor pressure
c. suction pressure
d. root pressure

5. Transport of water in stem takes place through:
a. phloem
b. xylem
c. epidermis
d. endodermis.

6. A root hair is:
a. extensive of cortical cell 
b. extension of epidermal cell
c. specialised multicellular structure
d. extension of endodermis

7. The space between the cell wall and cell membrane in a plasmolysed cell is filled with.
a. hypotonic solution 
b. isotonic solution
c. hypertonic solution
d. none of these

8. Mineral salts are absorbed by roots from the soil in the form of:
a. very dilute solution 
b. concentrated solution
c. hypertonic solution
d. very concentrated solution

9. Drooping of leaves of Mimosa plant is due to:
a. change in turgor pressure 
b. imbibition
c. plasmolysis
d. diffusion

10. Girdling in a tree results in the death of the tree due to:
a. starvation of root 
b. starvation of shoot
c. no conduction
d. no upward conduction of food

Question: Name the following :

1. Cell organelle which contains cell sap. _________

2. The tissue responsible for ascent of sap in plants. ___________

3. The pressure responsible for the movement of water molecules across the cortical cells of the root._______

4. Movement of molecules from a region of their higher concentration to a region of their lower concentration. _________

5. Tissue responsible for translocation of food _________

6. Inward movement of water molecules into the cell. __________

7. The mineral needed for chlorophyll formation __________

8. A plant whose leaves droop immediately on being touched. ___________

9. Process by which mineral salts are absorbed by the root. _________

10. Tissue responsible for conduction of water is a plant. _________

11. Process by which water enters the root hair. __________

12. The swollen leaf base as seen in Mimosa plant. ___________

13. The plant organ that helps in absorption of water and minerals. __________

14. Mineral needed by plants for protein synthesis ___________

15. Condition of the cell placed in a hypotonic solution. __________

16. A cell organelle which is concerned with osmoregulation. ___________

17. Process that leads to bursting of a marine fish when kept in fresh water. _______

18. Part of the root which absorbs soil water. ____________

Question: Give one word for each of the following :

1. Movement of substances from lower concentration to higher concentration utilizing cell energy.

2 A cell no longer charged with water due to loss of water.

3. Process by which living or dead cells absorb water by surface attraction.

4. A porous membrane which allows only the solvent molecules to pass.

5. An apparatus used to demonstrate osmosis.

6. Upward movement of water from roots to the leaves by xylem.

7. Forces of attraction between like molecules.

8. Pressure exerted by the cell wall on its inner contents.

9. Forces of attraction between unlike molecules.

10. Pressure exerted by cell contents on the cell wall in a turgid cell.

11. A cell in which cell membrane is pressed against cell wall due to accumulation of water.

12. The living membrane which allows only the solvent molecules to pass.

13. A process that occurs when a fresh water fish is placed in a sea.

14. Inward movement of water molecules into the cell across a semipermeable membrane.

15. Phenomenon by which liquids rise to great heights in tubes with narrow diameter.

16. The outward movement of solvent molecules across semi permeable membrane of the cell.

17. A mixture of water and dissolved salts contained in the vacuole.

18. A measure of the tendency of water molecules to diffuse out of it.

19. A cell no longer charged with water.

20. Shrinkage of protoplasm along with cell membrane away from cell wall when placed in a hypertonic solution.

Question: Given below are a group of terms. In each group the first pair indicates the relationship that exists between the terms. Rewrite and complete the second pair on similar basis. An example is done for you.
Example : Lung : Respiration :: Kidney : Excretion

1. Passive absorbtion: water :: Active transport: _________________
Ans. Active transport : Minerals

2. Nitrogen: Protein synthesis :: _________________: Chlorophyl formation

Ans. Magnesium : Chlorophyll formation

3. Chloroplast: photosynthesis :: vacuole : _________________
Ans. Vacuole : Osmoregulation

4. Xylem: water transport :: _________________ : food translocation
Ans. Phloem : food translocation

5. Natural membrane : goat’s bladder :: Artificial membrane: _________________
Ans. Artificial membrane : parchment paper

Question: a) State whether the following statements are True or False

1. If the xylem vessels are blocked, the plant will wilt. ________
Ans. True

2. Root hair is multicellular. ________
Ans. False – Root hair is unicellular

3. Exudation of sap from cut surface is indicative of root pressure. ________
Ans. True

4. Ascent of sap takes place through the pith. ________
Ans. False – Ascent of sap takes place through xylem.

5. Cell membrane is thin and freely permeable. ________
Ans. False – Cell wall is thin and freely permeable

6. Root hair is extension of cortical cell ________
Ans. False – Root hair is extension of epidermal cell.

7. Fixation of plant into the soil prevents soil erosion. ________
Ans. True

8. Absorbtion of water from soil occurs if soil solution is hypertonic _______
Ans. False – Absorbtion of water from soil occurs if soil solution is hypotonic.

9. When cell is placed in hypertonic solution, endosmosis occurs _______
Ans. False – When cell is placed in hypertonic sol, exosmosis occurs