Osmosis and Plasmolysis Questions in English

(B) Crenation refers to the process where cells shrivel or contract due to water loss.
This occurs when a cell is placed in a hypertonic solution,meaning the concentration of solutes outside the cell is higher than inside.
As a result,water moves out of the cell through osmosis,causing the cell to shrink or undergo crenation.

(B) Osmosis is a special type of diffusion that involves the movement of solvent molecules (usually water) through a semipermeable membrane from a region of higher water potential to a region of lower water potential. Therefore,the selective transmission through a semipermeable membrane is specifically termed as osmosis.

(B) Osmosis is a special type of diffusion of a liquid where solvent molecules move through a semipermeable membrane from a region of higher solvent concentration (or higher diffusion pressure) to a region of lower solvent concentration (or lower diffusion pressure).
Therefore,the correct process involves the movement of solvent particles across a semipermeable membrane.

(A) The goat bladder acts as a semi-permeable membrane.
Since the syrup inside the bladder has a higher solute concentration (hypertonic) compared to the pure water outside (hypotonic),water molecules will move from the vessel into the bladder through the process of osmosis.
Consequently,the volume of the liquid inside the bladder will increase.

(D) When a cell is placed in a hypertonic (strong) solution,the water potential outside the cell is lower than inside the cell.
This causes water to move out of the cell into the surrounding solution through the semi-permeable membrane,a process known as exosmosis.
As a result,the protoplasm shrinks and pulls away from the cell wall,causing the cell to become flaccid.

(A) When a cell is placed in a hypotonic solution,the concentration of water is higher outside the cell than inside.
Due to this concentration gradient,water moves into the cell through the process of endosmosis.
As water enters the cell,it exerts turgor pressure against the cell wall,causing the cell to swell and its volume to increase.

(A) Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration (which is equivalent to a region of lower solvent concentration).
Therefore,the solvent moves from a region of higher solvent concentration (hypotonic solution) to a region of lower solvent concentration (hypertonic solution) to equalize the concentrations on both sides of the membrane.

(A) When a cell is placed in a hypertonic solution,the concentration of solutes in the solution is higher than that inside the cell.
Due to osmosis,water moves out of the cell into the surrounding solution.
This loss of water causes the cell to shrink or reduce in size.
Therefore,the correct answer is $A$ (Hypertonic).

(C) Osmosis is the movement of water molecules across a semi-permeable membrane from a region of higher water potential to a region of lower water potential.
$A$,$B$,and $D$ involve the movement of water across cell membranes,which is an osmotic process.
In $C$,the movement of water through xylem vessels occurs due to the transpiration pull and the cohesive-adhesive properties of water molecules,which is a bulk flow process,not osmosis.

(A) When a potato slice is placed in a strong sugar solution (a hypertonic solution),the concentration of solutes outside the cells is higher than inside the cells.
Due to the process of exosmosis,water moves out of the potato cells into the surrounding solution.
As a result,the cells lose water,the protoplast shrinks away from the cell wall,and the cells become flaccid.

(B) When a plant cell is placed in a hypertonic solution,water moves out of the cell due to exosmosis.
As a result,the protoplast shrinks and pulls away from the cell wall,a process known as plasmolysis.
The cell wall is freely permeable to solutes and solvents,allowing the external hypertonic solution to enter the space between the cell wall and the shrunken plasma membrane (plasmalemma).
Therefore,the space between the cell wall and the plasmalemma is occupied by the hypertonic solution.

(B) When a grape is placed in a concentrated sugar solution,the external solution is hypertonic compared to the cell sap of the grape.
Due to the difference in water potential,water moves out of the grape cells into the surrounding solution through the semi-permeable membrane.
This process of water moving out of the cell is known as Exosmosis.
As a result,the grape shrinks.

(B) Incipient plasmolysis is the initial stage of plasmolysis where the cell membrane just begins to pull away from the cell wall.
When this cell is placed in a hypertonic solution (a solution with a higher solute concentration than the cell sap),water continues to move out of the cell due to osmosis.
This process of water moving out of the cell is called exosmosis.
As a result of continuous exosmosis,the cell undergoes further shrinkage of the protoplast,leading to more pronounced or complete plasmolysis.
Therefore,the cell will show more plasmolysis.

(C) Plasmolysis is the process where cells lose water in a hypertonic solution,causing the protoplast to shrink away from the cell wall.
This principle is used in agricultural practices to kill weeds by applying high concentrations of salt or fertilizers around them,which creates a hypertonic environment,leading to plasmolysis and the eventual death of the weed cells.

(C) The hydration of solute molecules refers to the process where water molecules surround and interact with solute particles.
This interaction effectively reduces the number of free water molecules available in the solution,thereby changing the concentration of the solution.
Since osmosis is the movement of water molecules from a region of higher water potential (lower solute concentration) to a region of lower water potential (higher solute concentration) through a semi-permeable membrane,it is directly dependent on the concentration of the solution.
Therefore,the hydration of solute molecules affects the process of osmosis.

(D) Osmosis is the movement of solvent molecules from a region of higher water potential to a region of lower water potential through a semi-permeable membrane.
$1$. Distribution of water: Osmosis facilitates the movement of water between cells,ensuring proper hydration and nutrient transport.
$2$. Turgor of guard cells: The opening and closing of stomata are regulated by the turgor pressure of guard cells,which is maintained by the osmotic influx and efflux of water.
$3$. Resistance to frost: Osmosis and the accumulation of solutes help lower the freezing point of the cell sap,providing resistance against frost damage.
Therefore,all the given options are correct.

(C) Osmosis is a vital process for plants.
$1$. The growth of young cells is facilitated by the osmotic pressure and the resulting turgor pressure,which helps in cell enlargement.
$2$. Turgor movements,such as the opening and closing of stomata or the drooping of leaves in 'Mimosa pudica' (touch-me-not plant),are regulated by changes in turgor pressure driven by osmotic water movement.
Therefore,both statements are correct.

(A) The $Potato$ $osmoscope$ is a classic experimental setup used to demonstrate the process of osmosis.
In this experiment,a hollowed-out potato tuber is placed in a beaker containing water.
$A$ concentrated sugar solution is poured into the hollow cavity of the potato.
Over time,the level of the sugar solution inside the cavity rises,which provides visual evidence that water molecules move from a region of higher water potential (outside the potato) to a region of lower water potential (inside the cavity) through the semi-permeable membrane of the potato cells.

(D) Osmosis is the spontaneous net movement of solvent molecules (water) through a selectively permeable membrane into a region of higher solute concentration (hypertonic solution) from a region of lower solute concentration (hypotonic solution).
This process aims to equalize the solute concentrations on both sides of the membrane.
Therefore,water moves from a region of higher water potential (hypotonic) to a region of lower water potential (hypertonic).

(C) membrane that allows the passage of solvent molecules but restricts the passage of solute molecules is known as a semipermeable membrane.
Parchment paper acts as a classic example of a semipermeable membrane used in laboratory experiments to demonstrate osmosis.

(B) solution is termed $Hypertonic$ when its osmotic pressure is higher than that of the cell sap.
In such a condition,water moves out of the cell due to osmosis,leading to plasmolysis.
Conversely,if the osmotic pressure of the outer solution is lower than the cell sap,it is called $Hypotonic$.
If the osmotic pressures are equal,it is called $Isotonic$.

(C) The peel of the $Tradescantia$ leaf is commonly used in laboratory experiments to demonstrate the process of plasmolysis.
This is because the cells of $Tradescantia$ have colored cell sap,which makes it easier to observe the shrinkage of the protoplast away from the cell wall under a microscope when placed in a hypertonic solution.

(B) Osmosis is the diffusion of water across a differentially or semi-permeable membrane. In a plant cell,the cell wall is freely permeable to water and solutes. The protoplast,which includes the cell membrane (plasma membrane),cytoplasm,and nucleus,acts as the semi-permeable barrier. Specifically,the plasma membrane is the primary structure that regulates the movement of substances into and out of the cell,thus acting as the semi-permeable membrane during osmosis.

(C) Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration.
While osmosis involves the movement of solvent, the process itself is defined by the presence and function of a $Semipermeable \ membrane$.
In biological systems, such as plant cells, the plasma membrane and tonoplast act as semipermeable membranes, which are essential for the occurrence of osmosis.

(A) Osmosis is the movement of solvent molecules from a region of higher water potential to a region of lower water potential through a semi-permeable membrane.
When two solutions become isotonic,their water potentials are equal,meaning there is no net movement of water.
Similarly,$DPD$ (Diffusion Pressure Deficit) is equivalent to the suction pressure of the cell.
When the $DPD$ of two systems becomes equal,the net movement of water stops,and the process of osmosis ceases.

(A) Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration.
In this case,pure water has a higher water potential compared to a colloidal suspension (which contains dispersed particles).
Therefore,water molecules will move from the region of pure water (higher water potential) to the region of the colloidal suspension (lower water potential) across the selectively permeable membrane.
Thus,the net movement of water will be towards the colloidal side.

(C) In a potato osmoscope,osmosis is demonstrated by the movement of water across a semi-permeable membrane.
For osmosis to be observed,the solute (sugar) must be unable to pass through the membrane,creating a concentration gradient.
$NaCl$ (salt) dissociates into $Na^+$ and $Cl^-$ ions in solution.
These ions are small enough to pass through the cell membranes of the potato tissue.
Because the salt ions can diffuse into the potato cells,they do not maintain the necessary osmotic pressure gradient required to demonstrate osmosis effectively.
Therefore,the potato tissue is permeable to these ions.

(A) Deplasmolysis is the process by which a plasmolysed cell regains its turgidity.
When a plasmolysed cell is placed in a $Hypotonic$ solution (a solution with a lower solute concentration than the cell sap),water enters the cell through the process of endosmosis.
This influx of water causes the protoplast to expand and press against the cell wall,reversing the effects of plasmolysis.

(A) Grapes will shrink when placed in a solution that is hypertonic to the cell sap of the grape.
If the water contains a high concentration of salts,the surrounding solution becomes hypertonic.
Due to this,water moves out of the grape cells into the surrounding solution through the process of exosmosis.
As a result,the grape loses water and shrinks.

(C) Plasmolysis occurs when a cell is placed in a hypertonic solution,causing water to move out of the cell due to osmosis,leading to the shrinkage of the protoplast.
When a cell is placed in a $KCl$ solution,$KCl$ acts as a solute that can slowly permeate the cell membrane.
Initially,the external concentration of $KCl$ is higher,causing rapid water loss (plasmolysis).
However,as $KCl$ ions slowly enter the cell,the osmotic potential inside the cell decreases.
This allows water to re-enter the cell,leading to the reversal of plasmolysis (deplasmolysis).

(C) When potato tissue is placed in a hypertonic solution,the water potential of the solution is lower than that of the potato cells.
This causes water to move out of the potato cells into the surrounding solution through the semi-permeable membrane,a process known as $Exosmosis$.
Due to the loss of water from the cells,the overall weight of the potato tissue decreases.

(B) Plasmolysis is the process where the protoplast shrinks away from the cell wall when a plant cell is placed in a hypertonic solution.
This occurs due to the movement of water out of the cell,a process known as exosmosis.
As water leaves the cell,the protoplasm loses its turgor pressure and shrinks,causing the cell to become flaccid.
Therefore,exosmosis is the primary mechanism responsible for plasmolysis.

(C) In the process of osmosis,there is no consumption or production of solvent molecules.
Osmosis is defined as the net movement of solvent molecules from a region of higher solvent concentration (hypotonic solution) to a region of lower solvent concentration (hypertonic solution) through a semi-permeable membrane.
Since the solvent molecules simply migrate from one side to the other without being created or destroyed,the total volume of the solvent in the system remains constant.

(B) Plasmolysis is the process of shrinkage of the protoplast from the cell wall when a plant cell is placed in a solution that has a higher solute concentration than the cell sap.
This type of solution is known as a $Hypertonic$ solution.
When a cell is placed in a $Hypertonic$ solution,water moves out of the cell into the surrounding medium through the process of $Exosmosis$.
As water leaves the cell,the protoplast shrinks away from the cell wall,resulting in plasmolysis.

(A) Osmosis is the spontaneous net movement or diffusion of solvent molecules (usually water) through a selectively permeable membrane from a region of high water potential (lower solute concentration) to a region of low water potential (higher solute concentration).
Therefore,water diffuses from a region of lower solute concentration to a region of higher solute concentration.

(A) When a plant cell is placed in distilled water (a hypotonic solution),water molecules move into the cell through the process of endosmosis.
As water enters,the cell contents exert pressure against the cell wall,known as turgor pressure.
This causes the cell to swell and become turgid.

(A) When excessive fertilizers are added to the soil,the concentration of solutes in the soil solution becomes higher than that inside the plant cells (hypertonic condition).
Due to this concentration gradient,water moves out of the plant cells into the soil through the process of exosmosis.
As a result,the cells lose turgor pressure,leading to the wilting of the plant.

(D) Plasmolysis occurs due to exosmosis,where water moves out of the cell when it is placed in a hypertonic solution.
As water leaves the cell,the protoplasm shrinks and pulls away from the cell wall.
This loss of water and the resulting shrinkage of the protoplast cause the cell to lose its turgidity and become flaccid.

(A) When a potato piece is placed in a highly concentrated salt solution (hypertonic solution),the water potential of the surrounding solution is lower than that of the potato cells.
This causes water to move out of the potato cells into the surrounding solution through the process of exosmosis.
As water leaves the cells,the protoplast shrinks away from the cell wall,a phenomenon known as plasmolysis.
Therefore,the potato piece becomes plasmolysed.

(A) When a plant cell is placed in a hypertonic solution (like $NaCl$ solution),the concentration of solutes outside the cell is higher than inside the cell.
This creates a water potential gradient where water moves from the cell to the outside environment through the semi-permeable membrane.
This process is known as exosmosis,which causes the cell to lose water and become flaccid or plasmolyzed.
Therefore,the correct option is $A$.

(D) When a plasmolysed cell is placed in a hypotonic solution (a solution with a lower solute concentration than the cell sap),water enters the cell through the process of endosmosis.
This influx of water causes the protoplast to expand and press against the cell wall,making the cell turgid again.
This process of reversing plasmolysis is known as deplasmolysis.

(B) When a cell is placed in a $Hypertonic$ solution,the concentration of solutes outside the cell is higher than inside the cell.
This creates a water potential gradient,causing water to move out of the cell into the surrounding solution through the process of $Exosmosis$.
As a result,the cell loses water and shrinks.

(C) The process of wilting in a plant follows a specific sequence of events:
$1$. $Exosmosis$: When a plant is placed in a hypertonic solution or faces water scarcity,water moves out of the cell.
$2$. $Plasmolysis$: As $exosmosis$ continues,the protoplast shrinks away from the cell wall,causing the cell to become flaccid.
$3$. $Wilting$: The loss of turgor pressure in the cells due to $plasmolysis$ leads to the drooping or wilting of the plant parts.

(D) Turgidity in a plant cell is achieved when water enters the cell through the process of endosmosis.
When a plant cell is placed in a hypotonic solution,water moves from the surrounding medium into the cell.
This inward movement of water increases the turgor pressure against the cell wall,making the cell turgid.

(B) When a plant cell is placed in a concentrated (hypertonic) salt solution,the water potential of the external solution is lower than that of the cell sap.
This causes water to move out of the cell into the surrounding solution through the process of exosmosis.
As water leaves the cell,the protoplast shrinks away from the cell wall,a phenomenon known as plasmolysis.
Therefore,the correct answer is $B$.

(C) Incipient plasmolysis is the initial stage of plasmolysis where the cell membrane just begins to pull away from the cell wall.
This occurs when the external solution is slightly hypertonic to the cell sap,meaning the osmotic concentration of the external solution is nearly equal to that of the cell sap (near isotonic).
At this stage,the net movement of water out of the cell is minimal,and the turgor pressure of the cell becomes zero.

(A) Roots absorb water from the soil through the process of osmosis.
Osmosis is the movement of water molecules from a region of higher water potential (lower solute concentration) to a region of lower water potential (higher solute concentration) through a semi-permeable membrane.
$A$ solution is called $Hypotonic$ when its osmotic concentration is lower than that of the cell sap.
When the external medium is $Hypotonic$,water moves into the root cells,allowing the roots to absorb water.

(B) Water absorption by root hairs occurs primarily through the process of osmosis.
Osmosis is the movement of water molecules from a region of higher water potential (lower solute concentration) to a region of lower water potential (higher solute concentration) through a semi-permeable membrane.
When the concentration of solutes in the root hair cell sap is high,the water potential inside the cell becomes lower than that of the surrounding soil water.
Consequently,water moves from the soil into the root hair cells to balance the concentration gradient.
Therefore,option $B$ is the correct answer.

(C) When a cut flower is placed in a solution,its freshness depends on its ability to maintain turgidity. Placing the flower in a slightly saline (hypertonic) solution helps in regulating the osmotic pressure within the flower cells. This prevents excessive water loss and maintains the turgor pressure of the cells for a longer duration,thereby keeping the flower fresh.

(D) Hugo de Vries was the first to demonstrate plasmolysis in plant cells. He specifically observed and proved the occurrence of plasmolysis in the sieve tubes of plants,which provided significant evidence regarding the nature of the protoplast and the permeability of the plasma membrane.