Tag: transport in plants

Questions Related to transport in plants

Which of the following statements is correct?

  1. Cells shrink in hypertonic solution and swell in hypotonic solution.

  2. Imbibition is a special type of diffusion when water is absorbed by no living parts.

  3. Most of water flow in the roots occur via the apoplast.

  4. All of the above


Correct Option: D
Explanation:

Following are the correct statements: 

(1) Cells shrink in a hypertonic solution and swell in the hypotonic solution.
(2) Imbibition is a special type of diffusion when water is absorbed by no living parts.
(3) Most of the water flow in the roots occur via the apoplast.
So, the correct answer is (d).

The principle used in pickling is

  1. Imbibition

  2. Endosmosis

  3. Plasmolysis

  4. None of the above


Correct Option: A

Absorption of water from soil by seeds increases the _________ thus helping seedlings to come out of soil.

  1. DPD

  2. Diffusion pressure

  3. Imbibition pressure

  4. Solute potential


Correct Option: C
Explanation:

Imbibition is the initial step in the germination of the seeds. When mature seeds are sown in soil they imbibe water and swell. The water is imbibed first by seed coat and then by other tissues of embryo and endosperm. The process of imbibition is important ot initiate the seed germination. the pressure that an imbibant develops when submerged in pure imbibing liquid is called imbibition pressure.

The practice of breaking of rocks during rainy season by inserting wooden pegs in them is based on the phenomenon of ______________.

  1. Imbibition pressure

  2. Turgor pressure

  3. Osmotic pressure

  4. Wall pressure


Correct Option: A
Explanation:

Imbibition pressure generated during germination of seeds and spores is so enormous that it can break asphalt roads and concrete pavements. In older times, the imbibition pressure was used in breaking the rocks and stones. Dry wooden stakes, if driven into a small crack in a rock and then soaked, can develop enough pressure to split the rock.

Movement of solvent molecule from a region of its higher concentration to a region of its lower concentration through a semi-permeable membrane, is referred to as.

  1. Simple diffusion

  2. Facilitated diffusion

  3. Osmosis

  4. Active transport


Correct Option: C
Explanation:

When the two solutions having different osmotic concentrations are separated by means of a semipermeable membrane, the molecules of solvent or water move from the region of their higher diffusion pressure (or free energy) to the region of their lower diffusion (or free energy). This movement of water or solvent is called osmosis.

Choose the correct answers from the alternatives given.
The first process by which water enters into the seed coat when a seed is placed in a suitable situation for germination is

  1. Root pressure

  2. Absorption

  3. Osmosis

  4. Imbibition


Correct Option: D
Explanation:

Imbibition is the process of absorption of water by hydrophilic solid particles. It is a special type of diffusion as the water moves along its concentration gradient. The classical example includes the absorption of water by seeds. This process plays an important role in the germination of seed, rupturing of the seed coat, and the emergence of seedlings is due to imbibition pressure developed by the seed kernel.

Hence, the correct answer is 'Imbibition'.

The uniformly sweet taste of coffee or tea is due to

  1. Spreading

  2. Permeability

  3. Distribution

  4. Diffusion


Correct Option: D
Explanation:

Coffee and tea tastes uniformly sweet due to the diffusion of solvent from the high concentration to the lower concentration. There is no membrane and it is not the case of osmosis and permeability.

So the correct optoin is D.

Read the given statements and select the correct ones.
(i) A membrane which permits the passage of pure solvent molecules to pass through it and not the solute particles is called semi-permeable.
(ii) A membrane which allows some substances to pass through it more readily than others is known as selectively/differentially permeable.
(iii) All living biological membranes are perfectly semipermeable.

  1. (i) and (iii)

  2. (ii) and (iii)

  3. (i) and (ii)

  4. (i), (ii) and (iii)


Correct Option: A
Explanation:
There are certain membranes, which allow penetration of only solvent molecules but not the solute particles. Such membranes are known as semi-permeable. Examples of such membranes are cellophane, fish and animal bladders, egg membrane, plasma membrane, etc. The biological membranes are not perfectly semi-permeable. They allow to pass solute molecules only up to a certain extent and are, therefore, selective in nature. They are known as selectively or differentially permeable membranes. All living biological membranes are differentially permeable membranes, which allow some substances to pass through it more readily than others.
So, the correct answer is '(i) and (iii)'.

Essence of environmental sciences involve:

  1. Social aspect

  2. Political aspect

  3. Economic aspect

  4. All of above


Correct Option: D

Monovalents like $Na^+$, $K^+$ .......... membrane permeability, while divalents like $Ca^{2+}$ .......... the same.

  1. Increase, Decrease

  2. Decrease, Increase

  3. Increase, Increase

  4. Decrease, Decrease


Correct Option: B
Explanation:
The permeability of plasma membrane increase with small sized ions and decrease with large sized ions because small sized molecules can easily diffuse across the plasma membrane.
Since, divalent molecules are smaller than monovalent molecules, hence, the permeability of plasma membrane increase with divalent cations like calcium and decrease with monovalent ions like sodium and potassium..
So, the correct answer is 'Decrease, Increase'.