Transport in Plants
Question 1
In a plant organ, which is covered by periderm and the stomata are absent, some gaseous exchange still takes place through
A pneumatophores
B trichomes
C aerenchyma
D lenticels
Ans 4
Question 2
The carbohydrates synthesized in the leaves are transported through sieve tubes most commonly in the form of
A glucose
B triose sugar
C sucrose
D soluble starch
Ans 3
Question 3
Phenylmercuric acetate
A reduces transpiration rate
B reduces photosynthesis
C reduces respiration
D kills the plant
Ans 1
Question 4
The amount of water held by the soil after drainage is known as
A Mineral water
B Soil water
C Field capacity
D Gravitational capacity
Ans 3
Question 5
In soil, water available for plants is
A Capillary water
B Hygroscopic water
C Gravitational water
D Chemically bound water
Ans 1
Question 6
Turgidity of the cells is maintained by
A osmotic pressure
B wall pressure
C turgor pressure
D diffusion pressure
Ans 3
Question 7
Wilting of a plant results from excessive
A respiration
B photosynthesis
C absorption
D transpiration
Ans 4
Question 8
The phytohormone, which increases the concentration of potassium in guard cells is also responsible for the induction of
A Cell division
B Triple response growth
C Apical dominance
D Abscission
Ans 1
Question 9
Potometer works on the principle of
A Osmotic pressure
B Amount of water absorbed equals the amount transpired
C Potential difference between the tip of the tube and that of the plant
D Root pressure
Ans 2
Question 10
According to Steward’s starch hydrolysis theory, which one of the following is the principal reason for the opening of stomata during daytime?
A Photosynthetic utilization of CO2 in guard cells.
B Influx of K+ ions into guard cells under the influence of ABA hormone.
C Conversion of sugar into starch in guard cells.
D Efflux of K+ ions from guard cells under the influence of ABA hormone.
Ans 1
Question 11
The osmotic potential and pressure potential of three cells (A, B, C) located in different parts of an actively transpiring plant are given below:
Cell Osmotic Potential (MPa) Pressure Potential (MPa)
A – 0.87 0.44
B – 0.92 0.34
C – 0.68 0.27
Identify these three cells as root hair, root cortical and leaf mesophyll cells respectively. The correct answer is.
A C, A, B
B A, C, B
C A, B, C
D B, C, A
Ans 1
Question 12
A leaf peeling of Tradescantia is kept in a medium having 10% NaCl. After a few minutes if we observe the leaf peel under the microscope, we are likely to see
A Entry of water into the cell
B Exit of water from the cell
C Diffusion of NaCl into the cell
D The cells bursting out
Ans 2
Question 13
Study the following table showing the components of water potential in closely arranged mesophyll cells namely A, B and C.
Cell Osmotic Potential (MPa) Pressure Potential (MPa)
A – 0.21 0.05
B – 0.22 0.02
C – 0.23 0.05
Identify two of the following which show correct direction of water movement between two cells. I. A → B, II. B → C, III. C → A, IV. C → B The correct pair is
A I, II
B II, III
C I, IV
D II,IV
Ans 3
Question 14
Two cells A and B are contiguous. Cell A has osmotic pressure 10 atm, turgor pressure 7 atm and diffusion pressure deficit 3 atm. Cell B has osmotic pressure 8 atm, turgor pressure 3 atm and diffusion pressure deficit 5 atm. The result will be:
A No movement of water
B Movement of water from cell B to A
C Movement of water from cell A to B
D Equilibrium between the two
Ans 3
Question 15
Assertion: When dried seeds of pea are placed in a tin and water added up to their upper level and then a lid is put lightly over it. Within an hour, the lid will be blown off.
Reason: Due to rapid cell division in pea seeds.
A Both Assertion and Reason are true and Reason is the correct explanation of the Assertion.
B Both Assertion and Reason are true but the Reason is not the correct explanations of Assertion.
C Assertion is true, but Reason is false.
D Both Assertion and Reason are false.
Ans 3
Level 2
Question 1
Stomata open is due to accumulation of
A K+
B Na+
C Ca+
D Mg+
Ans 1
Question 2
Attraction of water molecules to polar surfaces is known as
A Cohesion
B Capillarity
C Surface tension
D Adhesion
Ans 4
Question 3
Which of the following is not a purpose of transpiration?
A Supplies water for photosynthesis
B Helps in translocation of sugars from source to sink
C Maintains shape and structure of the plants
D Transports minerals from the soil to all parts of the plant
Ans 2
Question 4
A soil sample is found to have 25% of its volume occupied by soil water. Of this, 10% is hygroscopic water and .the remaining is capillary water. What is the field capacity of this soil?
A 10%
B 15%
C 25%
D 35%
Ans 3
Question 5
When the conditions are dry, a grass leaf curls inward to minimize water loss due to presence of
A Thick cuticle
B Large xylem cavities
C Parallel venation
D Bulliform cells
Ans 4
Question 6
Cohesion theory of water movement in plants was put forth by
A Henry Dixon
B F. F. Blackman
C Melvin cycle
D Hans. A. Krebs
Ans 1
Question 7
Which of the following force is responsible for raising water up to 100 m of tall plants?
A Root pressure
B Capillary action
C Transpiration pull
D Air pressure
Ans 3
Question 8
The first process by which water enters into the seed coat when a seed is placed in suitable environment for germination is
A Osmosis
B Imbibition
C Absorption
D None of these
Ans 2
Question 9
When the concentration of the soil solutes is low, the absorption of water is
A Remain normal
B Decreased
C Increased
D Stopped
Ans 3
Question 10
When pea seeds and wheat grains are soaked in water, pea seeds showed more swelling than the wheat. The reason is
A Cell membrane of pea seeds is more permeable
B Presence of less hydrophilic colloids in the wheat grains
C Imbibition capacity of proteins is more than that of starch
D Cell walls of wheat grains are less permeable
Ans 3
Question 11
Which one of the following denotes the water potential of the mesophyll cell in wilted condition?
A Greater than the value of its osmotic potential
B Equal to the value of pressure potential
C Equal to the value of osmotic potential
D Equal to zero
Ans 3
Question 12
Identify the correct relationship with reference to water potential of a plant cell.
A ψw = ψm + ψs + ψp
B ψw = ψm + (ψs – ψp)
C ψw = ψm – (ψs + ψp)
D ψw = ψm – ψs – ψp
Ans 1
Question 13
Study the following lists and choose the correct option.
List - I List - II
A. Water potential of 10% salt solution I. Positive
B. Pressure potential in a normal cell II. Negative
C. Pressure potential in a plasmolysed cell III. Positive
C. Metric potential on the surface of the wood IV. Negative
V. Zero
The correct match is :
A A - II, B - III, C - V, D - IV
B A - III, B - IV, C - II, D - I
C A - I, B - II, C - IV, D - III
D A - V, B - IV, C - II, D - I
Ans 1
Question 14
The values osmotic potential 'π' and pressure potential 'ρ' of cells A, B, C and D are given below:
Cell π ρ
Cell A –1.0 0.5
Cell B –0.6 0.3
Cell C –1.2 0.6
Cell D –0.8 0.4
Identify the correct sequence that shows the path of movement of water from among the following:
A D → C → A → B
B B → D → A → C
C B → C → D → A
D C → B → A → D
Ans 2
Question 15
Study the following table:
(I) Peperomia - Leaf succulent - Leaf epidermal cells store water
(II) Calotropis - Non-succulent - Root cells with thickened cell walls
(III) Tribulus - Ephemeral - Stem stores water
(IV) Ammophila - Dicot plant - Rolling in of leaves to check water loss
Identify the correct pair of answers.
A I, II
B I, III
C II, III
D II, IV
Ans 1
Level 3
Question 1
Humidity in atmosphere decreases rate of
A glycolysis
B photosynthesis
C transpiration
D growth
Ans 3
Question 2
Guttation is the result of
A Diffusion
B Root pressure
C Osmosis
D Transpiration
Ans 2
Question 3
Hydathodes are also called
A guard cells
B sunken stomata
C water stomata
D subsidiary cells
Ans 3
Question 4
Graham’s Law is correlated with
A Osmosis
B Osmoregulation
C Diffusion
D Adsorption
Ans 3
Question 5
The sugarcane Plant has
A reticulate venation
B pentamerous flowers
C dumb bell-shaped guard cells
D capsular fruits
Ans 3
Question 6
If water enters in a cell, the pressure exerted by its swollen protoplast is
A Osmotic pressure
B Diffusion pressure deficit
C Turgor pressure
D Imbibition
Ans 3
Question 7
Which one of the followings establishes the barrier to the apoplastic movement of solutes into the vascular cylinder?
A Intracellular spaces
B Plasma membrane
C Casparian strips
D Plasmodesmata
Ans 3
Question 8
The direction of water in the leaflets of Cycas from midrib is
A lateral
B downward
C upward
D both downward and upward
Ans 1
Question 9
Which of the following is the most accepted theory for movement of water through plants?
A Passive transport
B Capillarity
C Cohesion theory
D Root pressure
Ans 3
Question 10
With an increase in the turgidity of a cell, the wall pressure will
A increase
B decrease
C fluctuate
D remain unchanged
Ans 1
Question 11
Munch hypothesis is based on
A Translocation of food due to imbibition force.
B Translocation of food due to TP gradient and imbibition force.
C Translocation of food due to Turgor Pressure (TP) gradient.
D None of these
Ans 3
Question 12
The translocation of organic solutes in sieve tube members is supported by
A P-proteins
B Root pressure and transpiration pull
C Cytoplasmic streaming
D Mass flow involving a carrier and ATP
Ans 4
Question 13
Column I lists some principles, pertaining to physiology of plants. Column II lists the names of scientists who proposed the idea. Match the two columns. Identify the correct choice from those given
Column - I Column - II
A. Mass flow hypothesis p. J. C. Bose
B. Relay pump theory q. Strasburger
C. Transpiration pull theory r. Munch
D. Pulsatile movement theory s. Godlewski
t. Dixon and Jolly
A A - r, B - s, C - p, D - t
B A - r, B - s, C - t, D- p
C A - s, B - r, C - t, D - p
D A - s, B - r, C - p, D - t
Ans 2
Question 14
Opening and closing of stomata is due to the:
A Gaseous exchange
B Change in Turgor pressure of guard cells
C Hormonal change in guard cells
D Respiration
Ans 2
Question 15
Water will be absorbed by root hair when
A concentration of salts in the soil is high
B concentration of solutes in the cell sap is high
C plant is rapidly respiring
D they are separated from soil by a permeable membrane
Ans 2
Level 4
Question 1
Due to low atmospheric pressure, the rate of transpiration will
A increase
B decrease rapidly
C decrease slowly
D remain unaffected
Ans 1
Question 2
Guard cells help in
A Transpiration
B Protection against grazing
C Fighting against infection
D Guttation
Ans 1
Question 3
The transpiration is regulated by the movements of
A Subsidiary cells of the leaves
B Guard cells of the stomata
C Mesophyll tissue cells
D Epidermal cells of the leaves
Ans 2
Question 4
Steroid hormones easily pass through the plasma membrane by simple diffusion because they
A Enter through pores
B Contain carbon and hydrogen
C Are water soluble
D Are lipid soluble
Ans 4
Question 5
Living cells placed in isotonic solution (0.9% saline) retain their size and shape. This is based on the concept of
A Facilitated diffusion
B Diffusion
C Osmosis
D Transpiration
Ans 3
Question 6
When a plant is girdled (ringed)
A the root and shoot die at the same time
B the shoot dies first
C the root dies first
D neither root nor shoot will die
Ans 3
Question 7
Transport of food material in higher plants takes place through
A Tracheids
B Transfusion tissue
C Companion cells
D Sieve elements
Ans 4
Question 8
The rupture and fractionation do not usually occur in the water column in vessel/ tracheids during the ascent of sap because of:
A Cohesion and adhesion
B Lignified thick walls
C Transpiration pull
D Weak gravitational pull
Ans 1
Question 9
Passage cells are thin-walled cells found in:
A Phloem elements that serve as entry points for substances for transport to other plant parts
B Endodermis of roots facilitating rapid transport of water from cortex to pericycle
C Central region of style through which the pollen tube grows towards the ovary
D Testa of seeds to enable emergence of growing embryonic axis during seed germination
Ans 2
Question 10
The relationship among different types of soil water can be summed up by the following equation:
A Echard = Hollard + Chresard
B Chresard = Hollard – Echard
C Chresard = Echard + Hollard
D Hollard = Chresard – Echard
Ans 2
Question 11
Select the correct events leading to the opening of the stomata
a. Decline in guard cell solutes
b. Lowering of osmotic potential of guard cells
c. Rise in potassium levels in guard cells
d. Movement of water from neighbouring cells into guard cells
e. Guard cells becoming flaccid
A a, c and d only
B b, c and d only
C a and e only
D b, d and e only
Ans 2
Question 12
Water is lost in a liquid state in some plants through hydathodes. These hydathodes
A do not show any specificity in opening and closing
B remain closed during day
C remain closed at night
D remain always open
Ans 4
Question 13
Passive absorption of water by the root system is the result of
A Tension on the cell sap due to transpiration
B Increased respiratory activity in root cells
C Forces created in the cells of the root
D Osmotic force in the shoot system
Ans 1
Question 14
In which of the following plants, there will be no transpiration?
A Plants growing in hilly regions
B Aquatic, submerged plants
C Plants living in deserts
D Aquatic plants with floating leaves
Ans 2
Question 15
Assertion (A): K+ ion accumulation found in Nitella depends on its respiratory activity.
Reason (R): Absorption of all ions in plants completely depends on the usage of metabolic energy.
The correct answer is
A A and R are true and R is the correct explanation of A
B A and R are true but R is not the correct explanation of A
C A is true but R is false
D A is false but R is true
Ans 3
Question 1
In a plant organ, which is covered by periderm and the stomata are absent, some gaseous exchange still takes place through
A pneumatophores
B trichomes
C aerenchyma
D lenticels
Ans 4
Question 2
The carbohydrates synthesized in the leaves are transported through sieve tubes most commonly in the form of
A glucose
B triose sugar
C sucrose
D soluble starch
Ans 3
Question 3
Phenylmercuric acetate
A reduces transpiration rate
B reduces photosynthesis
C reduces respiration
D kills the plant
Ans 1
Question 4
The amount of water held by the soil after drainage is known as
A Mineral water
B Soil water
C Field capacity
D Gravitational capacity
Ans 3
Question 5
In soil, water available for plants is
A Capillary water
B Hygroscopic water
C Gravitational water
D Chemically bound water
Ans 1
Question 6
Turgidity of the cells is maintained by
A osmotic pressure
B wall pressure
C turgor pressure
D diffusion pressure
Ans 3
Question 7
Wilting of a plant results from excessive
A respiration
B photosynthesis
C absorption
D transpiration
Ans 4
Question 8
The phytohormone, which increases the concentration of potassium in guard cells is also responsible for the induction of
A Cell division
B Triple response growth
C Apical dominance
D Abscission
Ans 1
Question 9
Potometer works on the principle of
A Osmotic pressure
B Amount of water absorbed equals the amount transpired
C Potential difference between the tip of the tube and that of the plant
D Root pressure
Ans 2
Question 10
According to Steward’s starch hydrolysis theory, which one of the following is the principal reason for the opening of stomata during daytime?
A Photosynthetic utilization of CO2 in guard cells.
B Influx of K+ ions into guard cells under the influence of ABA hormone.
C Conversion of sugar into starch in guard cells.
D Efflux of K+ ions from guard cells under the influence of ABA hormone.
Ans 1
Question 11
The osmotic potential and pressure potential of three cells (A, B, C) located in different parts of an actively transpiring plant are given below:
Cell Osmotic Potential (MPa) Pressure Potential (MPa)
A – 0.87 0.44
B – 0.92 0.34
C – 0.68 0.27
Identify these three cells as root hair, root cortical and leaf mesophyll cells respectively. The correct answer is.
A C, A, B
B A, C, B
C A, B, C
D B, C, A
Ans 1
Question 12
A leaf peeling of Tradescantia is kept in a medium having 10% NaCl. After a few minutes if we observe the leaf peel under the microscope, we are likely to see
A Entry of water into the cell
B Exit of water from the cell
C Diffusion of NaCl into the cell
D The cells bursting out
Ans 2
Question 13
Study the following table showing the components of water potential in closely arranged mesophyll cells namely A, B and C.
Cell Osmotic Potential (MPa) Pressure Potential (MPa)
A – 0.21 0.05
B – 0.22 0.02
C – 0.23 0.05
Identify two of the following which show correct direction of water movement between two cells. I. A → B, II. B → C, III. C → A, IV. C → B The correct pair is
A I, II
B II, III
C I, IV
D II,IV
Ans 3
Question 14
Two cells A and B are contiguous. Cell A has osmotic pressure 10 atm, turgor pressure 7 atm and diffusion pressure deficit 3 atm. Cell B has osmotic pressure 8 atm, turgor pressure 3 atm and diffusion pressure deficit 5 atm. The result will be:
A No movement of water
B Movement of water from cell B to A
C Movement of water from cell A to B
D Equilibrium between the two
Ans 3
Question 15
Assertion: When dried seeds of pea are placed in a tin and water added up to their upper level and then a lid is put lightly over it. Within an hour, the lid will be blown off.
Reason: Due to rapid cell division in pea seeds.
A Both Assertion and Reason are true and Reason is the correct explanation of the Assertion.
B Both Assertion and Reason are true but the Reason is not the correct explanations of Assertion.
C Assertion is true, but Reason is false.
D Both Assertion and Reason are false.
Ans 3
Level 2
Question 1
Stomata open is due to accumulation of
A K+
B Na+
C Ca+
D Mg+
Ans 1
Question 2
Attraction of water molecules to polar surfaces is known as
A Cohesion
B Capillarity
C Surface tension
D Adhesion
Ans 4
Question 3
Which of the following is not a purpose of transpiration?
A Supplies water for photosynthesis
B Helps in translocation of sugars from source to sink
C Maintains shape and structure of the plants
D Transports minerals from the soil to all parts of the plant
Ans 2
Question 4
A soil sample is found to have 25% of its volume occupied by soil water. Of this, 10% is hygroscopic water and .the remaining is capillary water. What is the field capacity of this soil?
A 10%
B 15%
C 25%
D 35%
Ans 3
Question 5
When the conditions are dry, a grass leaf curls inward to minimize water loss due to presence of
A Thick cuticle
B Large xylem cavities
C Parallel venation
D Bulliform cells
Ans 4
Question 6
Cohesion theory of water movement in plants was put forth by
A Henry Dixon
B F. F. Blackman
C Melvin cycle
D Hans. A. Krebs
Ans 1
Question 7
Which of the following force is responsible for raising water up to 100 m of tall plants?
A Root pressure
B Capillary action
C Transpiration pull
D Air pressure
Ans 3
Question 8
The first process by which water enters into the seed coat when a seed is placed in suitable environment for germination is
A Osmosis
B Imbibition
C Absorption
D None of these
Ans 2
Question 9
When the concentration of the soil solutes is low, the absorption of water is
A Remain normal
B Decreased
C Increased
D Stopped
Ans 3
Question 10
When pea seeds and wheat grains are soaked in water, pea seeds showed more swelling than the wheat. The reason is
A Cell membrane of pea seeds is more permeable
B Presence of less hydrophilic colloids in the wheat grains
C Imbibition capacity of proteins is more than that of starch
D Cell walls of wheat grains are less permeable
Ans 3
Question 11
Which one of the following denotes the water potential of the mesophyll cell in wilted condition?
A Greater than the value of its osmotic potential
B Equal to the value of pressure potential
C Equal to the value of osmotic potential
D Equal to zero
Ans 3
Question 12
Identify the correct relationship with reference to water potential of a plant cell.
A ψw = ψm + ψs + ψp
B ψw = ψm + (ψs – ψp)
C ψw = ψm – (ψs + ψp)
D ψw = ψm – ψs – ψp
Ans 1
Question 13
Study the following lists and choose the correct option.
List - I List - II
A. Water potential of 10% salt solution I. Positive
B. Pressure potential in a normal cell II. Negative
C. Pressure potential in a plasmolysed cell III. Positive
C. Metric potential on the surface of the wood IV. Negative
V. Zero
The correct match is :
A A - II, B - III, C - V, D - IV
B A - III, B - IV, C - II, D - I
C A - I, B - II, C - IV, D - III
D A - V, B - IV, C - II, D - I
Ans 1
Question 14
The values osmotic potential 'π' and pressure potential 'ρ' of cells A, B, C and D are given below:
Cell π ρ
Cell A –1.0 0.5
Cell B –0.6 0.3
Cell C –1.2 0.6
Cell D –0.8 0.4
Identify the correct sequence that shows the path of movement of water from among the following:
A D → C → A → B
B B → D → A → C
C B → C → D → A
D C → B → A → D
Ans 2
Question 15
Study the following table:
(I) Peperomia - Leaf succulent - Leaf epidermal cells store water
(II) Calotropis - Non-succulent - Root cells with thickened cell walls
(III) Tribulus - Ephemeral - Stem stores water
(IV) Ammophila - Dicot plant - Rolling in of leaves to check water loss
Identify the correct pair of answers.
A I, II
B I, III
C II, III
D II, IV
Ans 1
Level 3
Question 1
Humidity in atmosphere decreases rate of
A glycolysis
B photosynthesis
C transpiration
D growth
Ans 3
Question 2
Guttation is the result of
A Diffusion
B Root pressure
C Osmosis
D Transpiration
Ans 2
Question 3
Hydathodes are also called
A guard cells
B sunken stomata
C water stomata
D subsidiary cells
Ans 3
Question 4
Graham’s Law is correlated with
A Osmosis
B Osmoregulation
C Diffusion
D Adsorption
Ans 3
Question 5
The sugarcane Plant has
A reticulate venation
B pentamerous flowers
C dumb bell-shaped guard cells
D capsular fruits
Ans 3
Question 6
If water enters in a cell, the pressure exerted by its swollen protoplast is
A Osmotic pressure
B Diffusion pressure deficit
C Turgor pressure
D Imbibition
Ans 3
Question 7
Which one of the followings establishes the barrier to the apoplastic movement of solutes into the vascular cylinder?
A Intracellular spaces
B Plasma membrane
C Casparian strips
D Plasmodesmata
Ans 3
Question 8
The direction of water in the leaflets of Cycas from midrib is
A lateral
B downward
C upward
D both downward and upward
Ans 1
Question 9
Which of the following is the most accepted theory for movement of water through plants?
A Passive transport
B Capillarity
C Cohesion theory
D Root pressure
Ans 3
Question 10
With an increase in the turgidity of a cell, the wall pressure will
A increase
B decrease
C fluctuate
D remain unchanged
Ans 1
Question 11
Munch hypothesis is based on
A Translocation of food due to imbibition force.
B Translocation of food due to TP gradient and imbibition force.
C Translocation of food due to Turgor Pressure (TP) gradient.
D None of these
Ans 3
Question 12
The translocation of organic solutes in sieve tube members is supported by
A P-proteins
B Root pressure and transpiration pull
C Cytoplasmic streaming
D Mass flow involving a carrier and ATP
Ans 4
Question 13
Column I lists some principles, pertaining to physiology of plants. Column II lists the names of scientists who proposed the idea. Match the two columns. Identify the correct choice from those given
Column - I Column - II
A. Mass flow hypothesis p. J. C. Bose
B. Relay pump theory q. Strasburger
C. Transpiration pull theory r. Munch
D. Pulsatile movement theory s. Godlewski
t. Dixon and Jolly
A A - r, B - s, C - p, D - t
B A - r, B - s, C - t, D- p
C A - s, B - r, C - t, D - p
D A - s, B - r, C - p, D - t
Ans 2
Question 14
Opening and closing of stomata is due to the:
A Gaseous exchange
B Change in Turgor pressure of guard cells
C Hormonal change in guard cells
D Respiration
Ans 2
Question 15
Water will be absorbed by root hair when
A concentration of salts in the soil is high
B concentration of solutes in the cell sap is high
C plant is rapidly respiring
D they are separated from soil by a permeable membrane
Ans 2
Level 4
Question 1
Due to low atmospheric pressure, the rate of transpiration will
A increase
B decrease rapidly
C decrease slowly
D remain unaffected
Ans 1
Question 2
Guard cells help in
A Transpiration
B Protection against grazing
C Fighting against infection
D Guttation
Ans 1
Question 3
The transpiration is regulated by the movements of
A Subsidiary cells of the leaves
B Guard cells of the stomata
C Mesophyll tissue cells
D Epidermal cells of the leaves
Ans 2
Question 4
Steroid hormones easily pass through the plasma membrane by simple diffusion because they
A Enter through pores
B Contain carbon and hydrogen
C Are water soluble
D Are lipid soluble
Ans 4
Question 5
Living cells placed in isotonic solution (0.9% saline) retain their size and shape. This is based on the concept of
A Facilitated diffusion
B Diffusion
C Osmosis
D Transpiration
Ans 3
Question 6
When a plant is girdled (ringed)
A the root and shoot die at the same time
B the shoot dies first
C the root dies first
D neither root nor shoot will die
Ans 3
Question 7
Transport of food material in higher plants takes place through
A Tracheids
B Transfusion tissue
C Companion cells
D Sieve elements
Ans 4
Question 8
The rupture and fractionation do not usually occur in the water column in vessel/ tracheids during the ascent of sap because of:
A Cohesion and adhesion
B Lignified thick walls
C Transpiration pull
D Weak gravitational pull
Ans 1
Question 9
Passage cells are thin-walled cells found in:
A Phloem elements that serve as entry points for substances for transport to other plant parts
B Endodermis of roots facilitating rapid transport of water from cortex to pericycle
C Central region of style through which the pollen tube grows towards the ovary
D Testa of seeds to enable emergence of growing embryonic axis during seed germination
Ans 2
Question 10
The relationship among different types of soil water can be summed up by the following equation:
A Echard = Hollard + Chresard
B Chresard = Hollard – Echard
C Chresard = Echard + Hollard
D Hollard = Chresard – Echard
Ans 2
Question 11
Select the correct events leading to the opening of the stomata
a. Decline in guard cell solutes
b. Lowering of osmotic potential of guard cells
c. Rise in potassium levels in guard cells
d. Movement of water from neighbouring cells into guard cells
e. Guard cells becoming flaccid
A a, c and d only
B b, c and d only
C a and e only
D b, d and e only
Ans 2
Question 12
Water is lost in a liquid state in some plants through hydathodes. These hydathodes
A do not show any specificity in opening and closing
B remain closed during day
C remain closed at night
D remain always open
Ans 4
Question 13
Passive absorption of water by the root system is the result of
A Tension on the cell sap due to transpiration
B Increased respiratory activity in root cells
C Forces created in the cells of the root
D Osmotic force in the shoot system
Ans 1
Question 14
In which of the following plants, there will be no transpiration?
A Plants growing in hilly regions
B Aquatic, submerged plants
C Plants living in deserts
D Aquatic plants with floating leaves
Ans 2
Question 15
Assertion (A): K+ ion accumulation found in Nitella depends on its respiratory activity.
Reason (R): Absorption of all ions in plants completely depends on the usage of metabolic energy.
The correct answer is
A A and R are true and R is the correct explanation of A
B A and R are true but R is not the correct explanation of A
C A is true but R is false
D A is false but R is true
Ans 3
