In this lesson, you’ll learn what happens during plasmolysis and deplasmolysis and their relationship to water balance in plants. You’ll also learn where these processes occur in everyday life.
Plants are the basis of our entire ecosystem. They can be found in the food we eat, and help to clean the air we breathe. You may be surprised to find these crucial living things are made up of 90% water. That’s right, plants are mostly just water! So it’s probably not surprising that water balance, or homeostasis, is incredibly important in keeping plants healthy.When plants don’t get enough water, their cells shrink in a process called plasmolysis. But when we water them, the cells swell again during deplasmolysis.
Let’s take a closer look at each of these terms and what they mean for our green companions.
Before we explain plasmolysis, let’s talk a little about plant cell anatomy. Plant cells have a thick outer wall called a cell wall.
The cell wall prevents the plants from losing their shape, and holds them upright. Beneath the cell wall is the plasma membrane, which holds the goop inside the cell in. The goop inside the cell is called the cytoplasm. Here, important parts of the cell work together to keep the plant alive. The vacuole, located inside the cytoplasm, holds the water in a plant cell, like a water tower.During plasmolysis, plants don’t get enough water. The cytoplasm and plasma membrane shrivel up and pull away from the cell wall.
This causes the whole plant to wilt.
Now, let’s look at the converse process, deplasmolysis. The prefix ‘de’ means not, or absent. In deplasmolysis, water rushes into the cell, causing the cytoplasm and plasma membrane to swell as water is stored in the vacuole. The cytoplasm pushes against the cell wall, making the cell full. The cell does not burst due to the strength of the cell wall.
The pressure exerted by the water on the cell wall is called turgor pressure, and it’s one of the factors that make plants stand up straight.
So how does this water flow happen? The answer is a process called osmosis, which is the movement of water from where there is more water to where there is less water. You might be wondering what this has to do with plasmolysis? Well, every cell sits in an environment, or a solution in which water flows and tries to achieve a balance. If there is more water inside than outside the cell, water will flow out, which is what occurs during plasmolysis.
In winter, road crews put salt on roads during ice and snowstorms.
As the ice and snow melts, the salt solution becomes very concentrated. Let’s say it’s about 20% water and 80% salt. As this melted watery solution flows into the surrounding environment, plasmolysis occurs and plants may die. To preserve plant life, natural substrates like gravel, sand or dirt may be better choices for making roads safe.Now, let’s take a look at an example of deplasmolysis.
After buying some flowers for a friend, you decide to run some errands. When you arrive home, the flowers have wilted. Armed with your trusty knowledge of osmosis, you spring into action. You put the flowers in a vase and fill it with distilled water, which is free from contaminates.
Now there’s more water outside than inside the flowers, which allows them to take water in and gain turgor pressure. Within minutes, water starts flowing into the flowers and restores their straight shape! Science has saved the day!
Plasmolysis is the process of water leaving plant cells, allowing the cytoplasm and plasma membrane to shrink away from the cell wall. This causes plants to wilt.In deplasmolysis, water from the outside environment rushes into the cell through a process called osmosis, which creates turgor pressure. The cytoplasm and plasma membrane push against the cell wall, thereby helping the plant to stand upright again.In real life, the salting of roads in winter causes plasmolysis.
Deplasmolysis is helpful in the flower industry.