Transport in Plants Test

Result

Transport in Plants Test - 87

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

Choose the correct answers from the alternatives given.
The rate of transpiration in plants is more when

A
Atmosphere is dry

B
Temperature is high

C
Atmosphere is humid

D
Atmosphere is dry and temperature is high

Solution

Dry atmosphere means lack of moisture content in the air. Due to this, air has a lot of capacity to hold water and thus the rate of transpiration increases.
Similarly, high temperatures evaporate the water at a much higher rate thus again increasing the rate of transpiration. Humid atmosphere already contains a lot of moisture and can not hold more water and thus transpiration rate decreases.
Hence, the correct answer is 'Atmosphere is dry and the temperature is high'.
Question 2
1 / -0

If cell A with OP = 5 and TP = 4 is surrounded by cells with OP = 3 and TP = 1, what will be the direction of water movement?

A
From other cells to cell A

B
From cell A to other cells

C
Water will not move

D
Data insufficient
Solution
- DPD or diffusion pressure deficit determines the flow of water. Water moves from low DPD to high DPD.
- DPD is given by: DPD = OP - TP.
In cell A, DPD = 5 - 4 = 1.
In other cells, DPD = 3 - 1 = 2.
Since, water moves from low DPD to high DPD, here the movement occurs from cell A to the other cells.
Hence, the correct answer is 'From cell A to other cells'.
Question 3
1 / -0

What would be the $$\Psi_p$$ of a flaccid cell?

A
Positive

B
Negative

C
Zero

D
Cannot be determined

Solution

Pressure potential refers to the positive pressure developed in a cell due to the entry of water through osmosis. In a turgid cell, the pressure potential is usually positive because water enters into the protoplast that generates turgor pressure. The pressure potential of a flaccid cell is usually zero because the water potential and pressure potential within a flaccid cell is equal. Thus, the pressure potential of a flaccid cell would be zero.
Question 4
1 / -0

The value of water potential $${ \Psi }_{ w }$$ for a solution at atmospheric pressure is :-

A
$${ \Psi }_{ w }={ \Psi }_{ s }$$

B
$${ \Psi }_{ w }=zero$$

C
$${ \Psi }_{ w }=-{ \Psi }_{ s }$$

D
$${ \Psi }_{ w }={ \Psi }_{ s }+{ \Psi }_{ p }$$

Solution

The value of water potential $${ \Psi }_{ w }$$ for a solution at atmospheric pressure is equal to the solute potential i.e., $${ \Psi }_{ w }={ \Psi }_{ s }$$. This happens because, at atmospheric pressure, there is no hydrostatic pressure on water in the cell. As a result, the value of Pressure potential is effectively zero. Subsequently making water potential equal to solute potential. As we know, Water potential = solute potential + pressure potential, but pressure potential is equal to zero. Hence, $${ \Psi }_{ w }={ \Psi }_{ s }$$.
So, the correct option is '$${ \Psi }_{ w }={ \Psi }_{ s }$$'.
Question 5
1 / -0

Osmotic pressure at sink decreases in phloem transport because

A
Sugar is transported through phloem as sucrose

B
Loading of phloem at source sets up a water potential gradient

C
Sugar removed from phloem sap at sink is either utilised to release energy or converted into starch or cellulose

D
Water passes out from phloem sap to the xylem vessel at sink
Solution
Osmotic pressure is the pressure which is applied when the molecules of solvent flow from higher to lower concentration through the semipermeable membrane. This is explained in the 'Pressure flow hypothesis' given by Munch in 1927.
According to this hypothesis, all the organic substances move from higher to lower concentration maintaining pressure. Due to the active transport of sugars will move out of the phloem and transported to another part of the cells and convert them into energy.
Since all the sugars are moved from the phloem and the osmotic pressure gets decreased and the water moves out of the phloem and towards the cell.
So, the correct option is 'Sugar removed from phloem sap at sink is either utilised to release energy or converted into starch or cellulose'.
Question 6
1 / -0

Which of the following explains bidirectional transport of solutes in phloem tissue

A
Mass flow hypothesis

B
Transcellular strands hypothesis

C
Electro-osmotic hypothesis

D
All of these

Solution

The Pressure Flow Hypothesis, also known as the Mass Flow Hypothesis, is the best-supported theory to explain the movement of sap through the phloem. It was proposed by Ernst Munch, a German plant physiologist in 1930. The movement in phloem is bidirectional, whereas, in xylem cells, it is unidirectional (upward).
So, the correct option is, 'Mass flow hypothesis'.
Question 7
1 / -0

0.5 M Sucrose solution develops a pressure of $$15$$ bars in an osmometer. Which of the following statement is WRONG for such a solution?

A
That its osmotic potential is $$-15$$ bars

B
That its water potential is $$-15$$ bars

C
That its pressure potential is $$-15$$ bars

D
That its osmotic pressure is $$+15$$ bars

Solution

Osmotic potential is the decrease in chemical potential of pure water due to the presence of solute particle in it. Osmotic potential is directly proportional to the solute concentration. The water potential is addition of osmotic potential and pressure potential. Pressure potential or turgor pressure of the flaccid cell is zero. Osmotic pressure is the pressure exerted by the solutes.
It is given that 0.5 M Sucrose solution develops a pressure of 15 bars in an osmometer. Hence, the osmotic pressure of the given solution is -15 bars. Its pressure potential is 0 bars. Its water potential is -15 bars. Its Osmotic pressure is +15 bars.
Thus, the correct answer is 'That its pressure potential is −15 bars.'
Question 8
1 / -0

The function of Anti-transpirants is:

A
Reduce the rate of transpiration without affecting carbon assimilation

B
Reduce the rate of transpiration affecting carbon assimilation

C
Reduce the rate of transpiration affecting growth of plant

D
Reduce the rate of transpiration affecting protein synthesis of plant

Solution

Anti-transpirants are compounds applied to the leaves of plants to reduce transpiration. They are used to preserve and protect plants from drying out too quickly. They are also used to protect leaves from the salt burn and fungal diseases. Anti-transpirants reduce the stomatal opening and increase the leaf resistance to water vapour diffusion without affecting carbon dioxide uptake.
So, the correct answer is 'Reduce the rate of transpiration without affecting carbon assimilation'.
Question 9
1 / -0

What is the direction of net osmotic movement of water of a solution $$A$$ enclosed in a semipermeable membrane having an osmotic potential $$-30$$ bars and pressure potential $$5$$ bars is surrounded in a solution $$B$$ of osmotic potential$$-10$$ bars and pressure potential$$= 0?$$

A
$$A \rightarrow B $$

B
$$B \rightarrow A$$

C
No movement

D
Equal amount

Solution

Water potential can be calculated as :
Water Potential = Solute Potential - Pressure Potential.
So, Water Potential for Cell A = -30 + 5 = -25
Water Potential for Cell B= -10 + 0 = -10
As Cell B has higher Water Potential, the water will move from Cell B to Cell A which has low Water Potential.
Hence, the correct answer is 'A to B'.
Question 10
1 / -0

Which is used to measure the rate of transpiration?

A
Atmometer

B
Psychrometer

C
Potometer

D
Porometer

Solution

Atmometer is a device used to measure the rate of water evaporation from a wet surface to the atmosphere and can be used to measure the rate of evapotranspiration.
A psychrometer is a device used to measure the rate of relative humidity in the atmosphere.
Potometer is a device used to measure the rate of water uptake by plants porometer is a device used to measure the area of the stomatal opening of leaves.
So, the correct answer is 'Potometre'.

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Transport in Plants Test - 87

Result

Transport in Plants Test - 87

Score

-

Rank

-

SHARING IS CARING

Question 1

Atmosphere is dry

Temperature is high

Atmosphere is humid

Atmosphere is dry and temperature is high

Solution

Question 2

From other cells to cell A

From cell A to other cells

Water will not move

Data insufficient

Solution

Question 3

Positive

Negative

Zero

Cannot be determined

Solution

Question 4

$${ \Psi }_{ w }={ \Psi }_{ s }$$

$${ \Psi }_{ w }=zero$$

$${ \Psi }_{ w }=-{ \Psi }_{ s }$$

$${ \Psi }_{ w }={ \Psi }_{ s }+{ \Psi }_{ p }$$

Solution

Question 5

Sugar is transported through phloem as sucrose

Loading of phloem at source sets up a water potential gradient

Sugar removed from phloem sap at sink is either utilised to release energy or converted into starch or cellulose

Water passes out from phloem sap to the xylem vessel at sink

Solution

Question 6

Mass flow hypothesis

Transcellular strands hypothesis

Electro-osmotic hypothesis

All of these

Solution

Question 7

That its osmotic potential is $$-15$$ bars

That its water potential is $$-15$$ bars

That its pressure potential is $$-15$$ bars

That its osmotic pressure is $$+15$$ bars

Solution

Question 8

Reduce the rate of transpiration without affecting carbon assimilation

Reduce the rate of transpiration affecting carbon assimilation

Reduce the rate of transpiration affecting growth of plant

Reduce the rate of transpiration affecting protein synthesis of plant

Solution

Question 9

$$A \rightarrow B $$

$$B \rightarrow A$$

No movement

Equal amount

Solution

Question 10

Atmometer

Psychrometer

Potometer

Porometer

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.