A cell placed in a hypotonic solution experiences a shift in its osmotic balance, causing water molecules to move into the cell. This influx of water increases the cell’s volume, leading to cell swelling and potential rupture. The cell membrane, acting as a selectively permeable barrier, plays a crucial role in this process, allowing water to enter while restricting the movement of solutes. Consequently, the cell’s internal environment becomes hypotonic relative to the external solution, resulting in osmotic pressure pushing water into the cell.
Changes in a Cell Placed in a Hypotonic Solution
When a cell is placed in a hypotonic solution – one with a lower solute concentration than the cell’s cytoplasm – water flows into the cell due to osmosis. This process occurs because the cell’s inner environment has a higher solute concentration than the outer solution, creating a higher osmotic pressure inside the cell.
What Happens to the Cell:
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Water Inflow: Water rapidly enters the cell, causing it to swell and expand.
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Cell Expansion: The cell’s cytoplasm and organelles expand, filling the increased volume.
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Cell Wall Response:
- In plants, the rigid cell wall resists the expansion, preventing cell rupture.
- In animal cells, the lack of a cell wall allows the cell to expand significantly, even forming a “bubble.”
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Selective Permeability: The cell membrane remains selectively permeable, allowing water and small solutes to pass in and out.
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Solute Concentration Changes: As the cell expands, the solute concentration within the cytoplasm decreases, becoming more similar to the hypotonic solution.
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Equilibrium: Eventually, water flow slows down as the osmotic pressure inside and outside the cell equalizes, reaching a new equilibrium.
Effects on Different Cell Types:
- Plant cells: Become turgid, with high osmotic pressure, due to their rigid cell walls.
- Animal cells: Can swell extensively, causing cell damage or even rupture in severe cases.
Table: Summary of Changes
| Cell Component | Change |
|---|---|
| Cell membrane | Remains selectively permeable |
| Cytoplasm and organelles | Expand |
| Cell wall | Resists expansion in plants |
| Solute concentration | Decreases inside the cell |
| Cell shape | Swells in animal cells, becomes turgid in plant cells |
Question 1: What occurs to a cell’s shape and volume when placed in a hypotonic solution?
Answer: When a cell is placed in a hypotonic solution, the concentration of solutes outside the cell is lower than the concentration of solutes inside the cell. This causes water to move into the cell by osmosis, increasing the cell’s volume and causing it to swell. The cell membrane becomes stretched and the cell may burst if the volume increase is too great.
Question 2: How does the movement of water affect the cell’s internal pressure?
Answer: The influx of water into the cell increases the pressure inside the cell. This pressure is called turgor pressure and it helps to maintain the cell’s shape. If the turgor pressure becomes too high, the cell may burst.
Question 3: What factors influence the rate at which a cell swells in a hypotonic solution?
Answer: The rate at which a cell swells in a hypotonic solution depends on several factors, including the concentration gradient of solutes between the cell and the solution, the permeability of the cell membrane to water, and the size of the cell. Cells with a high permeability to water will swell more quickly than cells with a low permeability. Larger cells will also swell more slowly than smaller cells.
Thanks for sticking with me through this watery adventure! I hope you’re feeling a bit more knowledgeable about what happens when cells take a dip in hypotonic solutions. If you’re curious about more cell-related shenanigans, be sure to come back and visit. I’ve got a whole bunch of other cell-tastic topics lined up that are sure to make your brain dance like a jellyfish in a blender!