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The Process of Plasmolysis
In this article, we will learn about the process of plasmolysis, different types, turgidity, examples and
many more
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If the cell is in a hypotonic solution,
deplasmolysis or cytolysis can occur, resulting in a reduced external osmotic pressure as well as a net
flow of water into the cell
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Turgidity
A plant cell in a hypotonic solution will absorb water by endosmosis, causing the protoplasm to push
against the cell wall, a situation known as turgor
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After a certain
point, known as complete turgor, plant cell walls resist further water entry, preventing plant cells from
bursting as animal cells do in similar conditions
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The
plant would collapse under its weight if the plant cells were not rigid
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Only
when there are no air spaces surrounding a cell will its turgor pressure begin to drop, eventually leading
to a higher osmotic pressure than the cell
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What is the Process of Plasmolysis?
Plasmolysis happens when a plant cell is immersed in a hypertonic solution as well as loses water and
hence turgor pressure: the cell’s protoplasm peels away from the cell wall, creating holes between the
cell wall and the membrane, and the plant cell shrinks and crumples
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Plants having this
state of cells wilt
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This is because exosmosis occurs when the solution around the cell becomes hypertonic, and the space
between the cell wall and the cytoplasm is filled with solutes as most of the water drains away, causing
the concentration inside the cell to become more hypertonic
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Plasmolysis can be
halted by placing the cell in a hypotonic solution
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Wax also helps the plant retain moisture
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Exosmosis causes the liquid component of the cell to flow out
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Because most animal cells have a phospholipid bilayer
(plasma membrane) as well as no cell wall, they shrink when exposed to these conditions
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Exosmosis is created in
the laboratory by immersing cells in strong saline or sugar (sucrose) solutions, which is commonly done
with Elodea plants or onion epidermal cells, which have coloured cell sap and so make the process
apparent
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Concave plasmolysis and convex plasmolysis are the two forms of plasmolysis
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The plasma membrane and the
contained protoplast shrink from the cell wall during concave plasmolysis as half-spherical, inwardly
curving pockets emerge between the plasma membrane as well as the cell wall
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Convex and Concave Plasmolysis
The osmosis process which results in a net outflow of molecules of water is known as plasmolysis
...
The formation of a space
between the cell wall as well as the plasma membrane is thus an indicator of plasmolysis
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The protoplasm shrinks inwardly concerning the cell wall in
concave plasmolysis
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Deplasmolysis can
reverse concave plasmolysis
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In nature, the plant regulates stomata and produces water-resistant wax to
avoid additional water loss
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Most of it is induced in the lab, for example, by
submerging plant cells in high-salt or high-sugar solutions
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g
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Importance of Plasmolysis
Plasmolysis is a plant cell’s response to a hypertonic environment, as described above
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When this happens, solutes fill the gap between
the cell wall and the protoplasm
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The partial separation of protoplasm from the cell wall signals
that the plant needs to correct the situation, prompting it to take in water from the soil & prevent
additional water loss through the stomatal mechanism
...
Excessive
plasmolysis, on the other hand, could result in irreversible structural integrity loss and, finally, death
...
Water loss
by exosmosis causes protoplasmic shrinkage, resulting in spaces between the cell wall as well as the
plasma membrane
...
Concave plasmolysis occurs when the protoplasm and plasma membrane contract, resulting in concave
pockets
...
As a result, a hypotonic solution can still be used to reverse the condition
...
The plasmolyzed cell in this scenario is around a protoplast that entirely
separates from the cell wall