potato in water and sugar experiment

Study of Osmosis by Potato Osmometer

A study of osmosis can be done using a potato osmometer. Osmosis is a phenomenon in which water moves from high solvent to low solvent concentration. The movement of water occurs between two compartments, separated by a semipermeable membrane .

The cell membrane of living organisms behaves as a semipermeable or selective membrane. The permeability of a selective membrane differs based on the size, charge and mass of different molecules.

Biological membranes are impermeable to large biomolecules and polar molecules like ions. But, non-polar molecules (lipids) and small molecules (oxygen, carbon dioxide etc.) can cross the selective barrier.

Water is the solvent that travels down or up the cell concentration gradient through osmosis. We can study water diffusion by creating two compartments and a semipermeable membrane in between.

The difference in the concentration of solutes or solvents between two compartments is the driving force responsible for water movement. Here, we need to note that only solvents can pass the selective barrier, not solutes.

Thus, the diffusion or distribution of water is related to osmosis . This post describes the meaning, requirements, procedure and results of the potato osmometer experiment.

Content: Study of Osmosis by Potato Osmometer

Potato osmometer, materials required, precautions.

It is a common experiment to demonstrate both endosmosis and exosmosis using a potato. Using a potato Osmoscope, we can study osmosis in a living system.

Here, a potato is used because the porous outer surface of the potato acts as a selective membrane .

• The contents within the cell form one compartment.
• The solution surrounding the cell forms another compartment.

Thus, a selective membrane separates two compartments and allows the process of osmosis .

• High solvent concentration in the cell surrounding.
• Low solvent concentration in the cavity of potato tuber.

Following the rule of osmosis, water in the cell surrounding enters the tuber cavity via the cell membrane.

• High solvent concentration in the cavity of potato tuber.
• Low solvent concentration in the cell surrounding.

Following the rule of osmosis, water in the potato cavity enters the surrounding solution via the cell membrane.

• Peeled off potato
• Concentrated sugar solution
• Petri plate

Video: Study of Osmosis

To perform the potato osmometer experiment, we need to follow the given procedure:

• First, peel off the large-sized potato using a peeler or knife.
• Then cut the upper and lower portions of the peeled potato using a knife. Through this step, we can easily place the potato on the Petri plate.
• Using a knife, make a cavity from the centre of the potato deep into the bottom, leaving some space. Here, the bottom of the potato will function as a selective membrane.
• Then, keep the potato on the Petri plate.
• To study endosmosis , pour water into half of the Petri plate. Next, pour the concentrated sugar solution into half of the cavity created in the potato.
• To study exosmosis , add concentrated sugar solution on the Petri plate and water into the cavity of the potato tuber.
• Then, fix a pin into the potato tuber-A and B to mark the level of sugar solution and water added into the cavity.
• Leave the plate undisturbed for some time until you notice any change.

Observation

• Observe the level of sugar solution in the cavity of potato tuber-A.
• Notice the level of water in the cavity of the potato tuber-B.

Potato Osmosis Experiment Results

• The level of sugar solution in the cavity of potato tuber-A increases . It occurs because the water in the Petri plate will move towards the cell with a high solute or low solvent concentration. This experiment shows endosmosis , as water goes into the cell or potato tuber.
• In contrast, the level of water in the cavity of potato tuber-B decreases . Here, water in the cavity moves toward the solution in the Petri plate due to the high solute concentration in the surrounding. This experiment shows exosmosis as water leaves the cell or potato tuber.
• The cavity should be deep enough by leaving a minimum thickness at the bottom.
• The sugar solution should have a high osmotic concentration.

The water movement from the Petri plate to the potato cavity or vice versa is due to the difference in the solvent or solute concentration between the two compartments.

Related Topics:

• Germination of Plant
• Difference Between Root and Stem
• Nerve Impulse
• Ozone Formation
• Examples of Adsorption in Daily Life

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Understanding Osmosis Using Potato Osmometer

To study by demonstrating the osmosis process by potato osmometer.

What is Osmosis?

Osmosis is the phenomena in which solvent molecules pass through a semi-permeable membrane from an area of higher concentration to an area of lower concentration. The process continues until the quantity of fluid is balanced or equalized in both regions, the region of higher concentration and the region of lower concentration of the semipermeable membrane. In other words, osmosis is the diffusion or movement of water from a region of higher water potential to a region of lower water potential.

In osmosis, what are solvent and solute?

The fluid that permeates through the semipermeable membrane is called the solvent, whereas the solute is the dissolved particles in the fluid.

What is the solution?

The mixture of solute and solvent form the solution.

List the different types of solutions.

The following are the types of solutions:

• Hypertonic solution – It is a solution with a high solute level. If living cells are placed in a hypertonic solution, because of lower concentration water moves out of the cell causing it to shrink and becomes plasmolyzed.
• Hypotonic solution – It is a solution with low concentration levels of solute. If living cells are placed in this solution, water passes into the cells because of higher water concentration in comparison to the cell causing the cells to swell and turn turgid.
• Isotonic solution – A solution is said to be isotonic if both solutions have an equal concentration of solute. If living cells are placed in an isotonic solution, no change is shown as there is the equal concentration on both the regions hence the cell retains its original shape.

Material Required

• A fresh large-sized potato tuber
• 20% sucrose solution
• Scalpel/blade
• A Bell pin needle that is labelled with a waterproof ink

• Slice the potato tuber into two equal halves with the help of a scalpel or a blade. The outer skin is to be peeled off. Since the tuber shape is irregular, slice the halves into squares
• From the mid-region of the tuber, scoop from the soft parenchyma, so as to form a tiny cavity of a square or a circular shape. At the base, the cavity prepared should have a minimum thickness.
• Fill up half the cavity with the freshly prepared 20% sugar solution. Into the cavity, fix a pin in a way that the mark is in the same line with the layer of the sucrose solution.
• Set up the osmometer in a Petri dish/beaker that is filled with water in a way such that 75% of the potato osmometer is immersed in water
• The set up should remain uninterrupted for close to 1 hour.
• Notice the sugar solution in the osmometer towards the end of the experiment
• Carry out the experiment with the help of water in the cavity and the sucrose solution in the petri dish/beaker.

Observation

After a period of time, within the osmoscope, the sugar solution rises and is seen coloured.

• An increase in the level of sucrose solution is observed in the osmometer. It is because of the entrance of water due to endosmosis from the beaker.
• Also, a water potential gradient is built between the sucrose solution in the external water and the osmometer.
• Though both the liquids are divided by living cells of the potato tuber, they allow the entrance of water into the sugar solution.
• This demonstrates the entrance of water into the sugar solution through the tissues of potato serving as a selectively permeable membrane.

Viva Questions

Q.1. What is plasmolysis?

A.1. It is a process, wherein the protoplasm of the plant cell turns round as a result of contraction when placed in a hypertonic solution due to exosmosis resulting in the decline in the tension of the cell wall.

Q.2. What is the significance of osmosis?

A.2. Osmosis maintains cell turgidity. It causes the transportation of nutrients and discharge of metabolic waste products. It preserves the interior environment of a living entity to maintain an equilibrium between the intracellular fluid levels and water.

Q.3. What is diffusion?

A.3. The movement of molecules from a region of higher concentration to a region of lower concentration. Osmosis is a type of diffusion.

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Osmosis Potato Experiment: DIY Science Project Ideas for Kids

Finished with your lesson on Osmosis but still confused? Then you need to perform this simple Osmosis experiment. All you need are some potato slices and water. Learn about osmosis with potato slices in this simple osmosis potato experiment. Performing science experiments for kids will enable them to understand challenging scientific concept they are learning in a much better way.

Step-by-Step Instructions on How to Perform Osmosis Potato Experiment

Osmosis is the process by which water or any other solvent moves towards a solution with a higher concentration through a semipermeable membrane. The molecules in the solution with a lower concentration move towards the solution with a higher concentration to equalize the concentration on both sides. Osmosis is how plants absorb water and nutrients from the soil.

A simple science experiment for kids like the Osmosis Potato Experiment helps kids understand the concept easily.

What You’ll Need?

If you leave cut slices of potatoes or apples or pears outside for a while, you’ll notice that they turn brown. Why do you think this discoloration occurs? When you cut these fruits or vegetables, it leaves the cells open. An enzyme present in the cells, polyphenol oxidase, reacts with the oxygen in the air and turns the fruit brown. But can you prevent the slices from turning brown and keep them fresher for longer? Let’s learn through this osmosis potato experiment.

Here is a list of things you’ll need to perform the experiment:

• 1 medium sized potato
• 2 – 4 tablespoons of salt
• Distilled water
• 2 medium sized mason jars or drinking glasses

How to Perform Osmosis Potato Experiment?

Follow these instructions to perform the experiment:

• Step 1: Peel and cut the potatoes so you have wedges that are neither too thick nor too thin. Ensure that the potato wedges are roughly the same size. Note down the color of the freshly cut potato wedges and how they feel when you touch them.
• Step 2: Pour 200ml of distilled water into one glass or jar. 
• Step 3: Into the second glass, pour 200ml of distilled water and add 2-4 tablespoons of salt. Stir it well until the salt is completely dissolved.
• Step 4: Add two potato wedges into each of the glasses and let them sit overnight.
• Step 5: The next day, you’ll notice a difference in both the glasses. The potato wedges in the glass with the unsalted water have become bigger, while the wedges in the salted water have shrunk slightly.
• Step 6: Take the potato wedges out of the unsalted water and try bending them. You’ll notice that it is firm and breaks but doesn’t bend. Additionally, it still has a white color like a freshly cut piece of potato.
• Step 7: Now take the potato wedges out of the salted solution and try to bend them. You’ll notice the wedges have turned brown and bend easily without breaking.

What You’ll See?

Once you’ve performed the experiment, help your child understand the science behind the osmosis experiment. Here are a few questions and answers that will help children understand the behavior of the potato wedges in the two different solutions.

• Why did the potato wedges in the glass with plain distilled water become bigger?

The potato wedges expand and become bigger because of osmosis. Potatoes are made of millions of cells and the cell walls act as a semipermeable membrane. The water molecules move into the potato through this membrane to balance the concentration levels. The water moving inside the potato cells causes it to expand and become bigger. 

• Why did the potato wedges in the glass with salt water shrink?

Again it’s because of osmosis. The salt solution has a higher concentration and the water inside the potato moves through the cell walls to balance the concentration in the saltwater. Since the water moves out of the potato wedge, it shrinks and becomes smaller. This is also the reason why the potato wedge in the salt solution becomes less rigid and bends easily.

• Why did the potato wedges in the salt solution change color?

The water moving out of the potato damages it’s cells, which causes them to release an enzyme called catechol oxidase. The enzyme in the potato cells reacts with the oxygen in the air and turns the wedges brown.

Other Way to Perform Osmosis Potato Experiment for Kids

Another cool way to see osmosis in action is to perform this experiment using grapes and raisins.

• 2 – 3 raisins
• 2 – 3 fresh grapes
• 3 – 4 tablespoons of sugar

Step-by-Step Guide on How to Perform Osmosis Potato Experiment

Follow these instructions to perform this experiment:

• Step 1: Add the 3 – 4 tablespoons of sugar into one glass of water and stir it until all the sugar is dissolved. Then add 2 -3 fresh grapes into the sugar solution.
• Step 2: Add 2 – 3 raisins to the second glass of water. Allow both glasses to sit for a few hours.
• Step 3: After a few hours, you’ll notice that the raisins in the plain water have plumped up almost as if they are grapes. The raisins have a higher concentration of sugar, so the water moves into the raisins to balance the amount of sugar. This causes the raisins to expand and plump up.
• Step 4: Meanwhile the grapes in the sugar solution have shrunk and almost look like raisins. The water surrounding the grapes has a higher concentration of sugar than water in the grape cells. So the water in the grape cells moves out to balance the level of sugar. This causes the grapes to shrink in size.

Can you use other vegetables or fruits to perform this experiment? Will sliced bananas or pineapples work the same way? The only way to know is to try. Looking for more cool science experiments to try with your kids? Check our kids learning section for more fun and informative science experiments.

Frequently Asked Questions on Osmosis Potato Experiment

What is osmosis.

Osmosis is the process by which a solution with a lower concentration moves towards a solution with a higher concentration through a semipermeable membrane to balance the levels of concentration.

Why does the potato in the salt solution shrink?

Potato cells also have water in them. The water in the potato tries to equalize the concentration by moving towards the saltwater. The loss of water causes the potato to shrink and also makes it bendy and less firm.

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Potato Osmosis Lab

Explore what happens to potatoes when you put them in a concentration of salt water and then pure water. Set up an osmosis potato lab and learn all about osmosis when you try this fun potato experiment with the kids. We are always searching for simple science experiments . Grab the free printable experiment below.

💡 What is Osmosis ? Learn more about osmosis through a variety of experiments.

• 2 tall glasses of distilled water (or regular)
• Free printable instructions (below)

INSTRUCTIONS:

STEP 1: Peel and then cut your potato into four equal pieces about 4 inches long and 1 inch wide.

STEP 2: Fill your glasses half way with distilled water, or regular water if no distilled is available.

STEP 3: Now mix 3 tablespoons of salt into one of the glasses and stir.

STEP 4: Place two pieces of potato into each glass and wait. Compare the potatoes after 30 minutes and then again after 12 hours.

What happened to the potato pieces? Here you can see how a potato can demonstrate the process of osmosis. Make sure to go back and read all about osmosis!

If you thought the salt water would have a higher concentration of solutes than the potato, and the distilled water would have a lower concentration you would be correct. The potato in the salt water shrinks because water moves from the potato into the more concentrated salt water.

In contrast, water moves from the less concentrated distilled water into the potato causing it to expand.

What Happens to a Potato in Salt Water?

The process of moving water across a semi-permeable membrane from a low concentrated solution to a high concentrated solution is called osmosis . A semi-permeable membrane is a thin sheet of tissue or layer of cells acting as a wall that allows only some molecules to pass through.

In plants, water enters the roots by osmosis. The plants have a higher concentration of solutes in their roots than in the soil. This causes water to move into the roots. The water then travels up the roots to the rest of the plant.

ALSO CHECK OUT: How Water Travels Through A Plant

Osmosis works in both directions. If you put a plant into water with a higher salt concentration than the concentration inside its cells, water will move out of the plant. If this happens then the plant shrinks and will eventually die.

Potatoes are a great way to demonstrate the process of osmosis in our potato osmosis experiment below. Discuss whether you think the potato or the water in each glass will have the greatest concentration of solutes (salt).

Which potato pieces do you think will expand and which will shrink in size as the water moves from a low concentration to a high concentration?

CLICK HERE TO GET YOUR FREE POTATO OSMOSIS EXPERIMENT!

More Osmosis Experiment Ideas

don’t stop with a potato osmosis lab; try one of these osmosis experiments to extend the learning.

• Rubber Egg Science
• Glowing Spinach
• Growing Gummy Bears
• Colored Celery Science

MORE FUN EXPERIMENTS TO TRY

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Osmosis of Potato in Glucose Solutions

Introduction: Osmosis of Potato in Glucose Solutions

A. Research Question

What problem/relationship are you going to investigate?

How does the concentration of glucose solution affect the mass of potato sticks?

(independent variable) (dependent variable)

Here's a short introductory video.

Step 2: Hypothesis

If the concentration of glucose outside the potato sticks increases then the mass of the potato sticks will decrease because water will move into an area with a higher concentration of solute.

Step 3: Variables

Step 4: ​Materials/Supplies Needed:

5.plate to hold potatoes

7.measring cup

8.potato cutter

9.pencil and notebook (for recording data)

Step 5: Procedure

1. Cut 15 pieces of potato into the same size or be within 4.4 - 6.5 grams

2. pour in a concentration of 1.00M of glucose (20ml Glucose) in a plate

3.pour in a concentration of 0.75M of glucose and the rest with water (15ml glucose) in a plate

4.pour in a concentration of 0.50M of glucose and the rest with water (10ml glucose) in a plate

5.pour in a concentration of 0.25M of glucose and the rest with water (5ml glucose) in a plate

6.pour in a concentration of 0.00M of glucose and the rest with water (0ml glucose) in a plate

7.mesure the mass of the potato before placing it into the solution

8.place three potatoes into each concentration

9.label each plate with the concentration and the mass of each potato before placement.

10.come back after 24hours and measure each potato's mass

Step 6: Results

Step 7: How to Calculate Percentage of Mass Change(POMC)

Step 8: Graph

Interpreting & Explaining the Data:

As seen in the graph, we can clearly see that as the glucose concentration decreases the percentage of decrease in the potato’s mass also decreases and eventually becomes an increase. This is the reason why I used the percentage in mass change as my y-axis and why I used the concentration of glucose solution as my x-axis, it is because it allows you to see if the percentage of mass change is affected by the concentration of glucose solution and water. The reason I used POCM is because it is much more accurate than the mass change of the potato, this is more accurate because not all the potatoes have the same mass as others. Samples with different mass their mass change can be different under the same experimental condition, but the POCM could be much accurate. This supports my hypothesis which states that “If the concentration of glucose outside the potato sticks increases then the mass of the potato sticks will decrease because water will move into an area with a higher concentration of solute.“ this is shown in the graph and the table. This can also be shown in the isotonic area of the graph. Between the concentration of 0.4 and 0.6, we can see there is a point where the mass change gets to zero, this is because the concentration of water inside the potato is isotonic to the glucose solution. My data validated to be reliable because I did not only attempt one trial per group instead I did three which increases the accuracy of my data results.

Step 9: Validating the Hypothesis

As seen in the table data the less concentration of glucose solution we add the less the decrease in mass and the more increase in mass we have. This is not only shown in the data table but also, it is shown in the graph which shows a steady decrease to an increase in mass, all of this supports and validates my hypothesis which states “If the concentration of glucose outside the potato, sticks increase then the mass of the potato sticks will decrease because water will move into an area with a higher concentration of solute.” This is validated by my graph and my experiment results. This is because water moves to an area with a higher concentration of solute. Which is , in this case, glucose solution. The more glucose there is the more amounts of water that will leave the potato which also means a decrease in mass as the glucose increases outside of the potato.

Step 10: Evaluation- Strengths of the Procedure

The method I experimented with did allow me to understand and test the idea I had, which is my research question. The procedure uses a total of 20 ml and different concentrations while keeping the total at 20 ml this allows my result to be accurate. The procedure asks to cut out 15 potato sticks and make them as similar as possible, this also allows my results to be accurate. Also, it measures the mass change in percentage (POCM) which can be more accurate than measuring the change in gram. All of this helps me to answer my research question as accurately as possible.

Limitations of the Procedure:

There are always possible sources of error. One of many that I found was the different masses of potato sticks. This can affect the mass change in grams which also makes it less accurate. There could have been some errors with measuring the correct amounts of solute, this could affect the accuracy of my result.

the picture is an example from https://www.youtube.com/watch?v=jTDATlaBV-o.. used due tp lack of materials, I was not able to get any of the materials needed due to lockdown

Step 11: Improvements to the Procedure

The procedure can be improved by keeping a constant temperature. This affects the experiment in multiple ways one of many is the concentration being different because of it being evaporated, since the temperature changes through out the day the concentration may change because of water being evaporated. This can be avoided by placing the petri dish in an environment with a constant temperature such as a fridge or a cooler. Another possible improvement is making sure that the potato is fully submerged into the solution throughout the experiment. This can be done my increase the total amount of liquids in the petri dish from 20ml to 30ml.

Going Further:

We can extend this investigation by using different solutions. Instead of using water which keeps glucose as a molecule, if we use salt water this can affect the state of glucose from a molecule to possibly turning into negative and positive ions. We can also change the dependent variable from measuring the mass of the potato to measuring the concentration of liquids, and seeing if there is more glucose solution left or more water left and why.

Step 12: What Does It Look Like in the Making?

When you're at home, having all the materials needed may be hard this is why I came up with a simpler way of extracting the potatoes at home. As you can see in the pictures below, I have used an old pen to pull out the potato sticks by puncturing the potato with the stick and then taking it out of the pen. As you can see the result is a very similar result to having all the materials of a lab. (The reason I couldn't use lab materials was because of lockdown and not being able to leave the house for materials related to this.)

Step 13: WORKS CITED

Asghari, Yas. “The Effect of Osmosis on Potatoes in Different

Concentrations of Sucrose Solutions | Natural Science | International Baccelaurate.” Athenology, Natural Science | International Baccelaurate | Athenology, 4 Apr. 2018, www.athenology.com/single-post/2017/09/23/The-effect-of-osmosis-on-potatoes-in-different-concentrations-of-sucrose-solutions.

Lobo, Tricia. “Science Experiments on the Osmosis of a Potato.” Sciencing, 2 Mar. 2019, sciencing.com/science-experiments-osmosis-potato-8360195.html.

Sauce, Science, director. Osmosis in Potato Strips - Bio Lab. YouTube, YouTube, 11 June 2017, www.youtube.com/watch?v=jTDATlaBV-o.

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Potato Osmosis Experiment

Osmosis is the movement of water from an area of its lower concentration to its higher concentration across a semi-permeable cell membrane. The addition of salt can change the concentration of water and the osmotic gradient. Salt can help us cook. In this osmosis experiment you will see how salt affects potato sticks.

WHAT YOU NEED

What you will do.

Ask an adult to help you cut the potato into even, rectangular sticks.

Do not consume any of the materials used in the experiment!

RECORD YOUR OBSERVATIONS AFTER 6-8 HOURS

CONCLUSIONS

What happened to the potato in the salt water? Why? Which way was the water moving?

What happened to the potato in the regular water? Why? Which way was the water moving?

Copyright @smorescience . All rights reserved. Do not copy, cite, publish, or distribute this content without permission.

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Experiments on Osmosis (With Diagram)

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The below mentioned article includes a list of four simple experiments on osmosis.

1. Experiment to demonstrate the osmosis by using sheet of cellophane or goat bladder:

Requirements:

Beaker, thistle funnel, goat bladder or sheet of cellophane, thread, water and sugar solution.

1. Cover the lower opening of the glass tube with the goat bladder or sheet of cellophane and tie it with the thread.

2. Fill in the interior of the tube with molasses, a concentrated sugar solution in water.

3. Place the whole apparatus in a beaker containing water, preferably distilled water.

4. Note the level of the water in the thistle funnel and keep the apparatus to note the results.

Observations:

Level of the water in the thistle funnel increases (Fig.2).

1. Movement of water through the goat bladder or cellophane sheet into the thistle funnel takes place.

2. Water concentration in beaker is 100% while in the sugar solution it is less than this, and, therefore, the water from the region of higher concentration moves towards the region of lower concentration. The movement is through a semipermeable membrane and so the experiment shows the phenomenon of osmosis.

3. The force, with which the solution level in the tube increases, arises from the pressure exerted by the diffusion of water molecules into the tube. This pressure is called osmotic pressure.

4. Stability of the water level in the funnel indicates that water concentration in both the beakers as well as funnel is same and thus osmosis stops.

2. Experiment to demonstrate osmosis with the help of potato osmometer:

Petri-dish, water, potato, sugar solution, cork and capillary tube.

1. Take a potato tuber, remove its outer covering from one end and cut the same end flat.

2. Scoop out a cavity from the other end of the tuber running almost upto the bottom.

3. Fill the cavity with the sugar solution and fit an airtight cork fitted with a capillary tube on the upper end of the cavity (fig. 3).

4. Place the capillary- fitted potato tuber in the water- filled petri-dish.

5. Mark the solution level in the tube and watch the experiment for some time.

After some time the level of the solution in the tube increases. Mark the level of solution when it stops to move.

The level in the capillary tube increases because of the fact that osmotic pressure of the sugar solution is higher than that of the water, and the water moves through the semipermeable membrane of potato from petri-dish into the cavity. So the experiment shows that phenomenon of osmosis.

3. Experiment to demonstrate the osmosis by the egg osmometer:

Egg membrane, dilute HCI, water through, graduated tube, sugar solution and stand.

1. Prepare an egg membrane by carefully removing waterproof shell of egg with the help of dissolving it away in dilute HCI.

2. Remove all the fat and protein-containing yellow material of the egg by making a hole on its one end.

3. Fill the sugar solution in the egg membrane through the hole and fit a graduated tube in the hole.

4. Place the complete apparatus in a water-filled trough (Fig. 4).

5. Note the level of sugar solution in the graduated tube and keep the apparatus undisturbed for some time.

Level of the sugar solution increases in the tube.

The level in the tube increases because of the fact that osmotic pressure of the sugar solution in the egg membrane is higher than that of water, and so the water from the trough passes through the egg membrane into the sugar solution thus increasing its level. Egg membrane is a semipermeable membrane.

4. Experiment to demonstrate the phenomenon of exosmosis and endosmosis:

Potato tubers (2), knife, conc. sugar solution, water, pin, beakers (2).

1. Remove the outer skin of the tubers and cut their one end flat with a sharp knife.

2. Scoop out a cavity from the other end of the tuber running almost upto the bottom as in experiment No. 14.

3. Fill the concentrated solution of sugar in the cavity of one tuber, and water in the other.

4. Mark the level of the sugar solution and water in the cavities with the help of pins.

5. Place the potato containing sugar solution in a beaker containing water, and the another potato containing water in its cavity in the beaker containing sugar solution (Fig. 5).

6. Keep and observe experiment for some time.

The level in the cavity containing sugar solution increases while the level decreases in the another tuber, i.e., in the cavity filled with water.

The level of the sugar solution in the first tuber increases because of the fact that water moves from the beaker into the cavity through the semipermeable membrane of potato. Thus it shows the phenomenon of endosmosis.

The level of the water in the second tuber decreases because of the fact that water moves from the cavity into the beaker through the semipermeable membrane of potato tuber. Thus it shows the phenomenon of exosmosis.

Related Articles:

• Experiment on Osmosis in Potatoes | Botany
• Top 6 Experiments on Osmosis (With Diagram)

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• Biology An Introduction 11
• Biology An Introduction
• Biology in Human Welfare 175
• Biomolecules
• Biotechnology 43
• Body Fluids and Circulation
• Breathing and Exchange of Gases
• Cell- Structure and Function
• Chemical Coordination
• Digestion and Absorption
• Diversity in the Living World 125
• Environmental Issues
• Excretory System
• Flowering Plants
• Food Production
• Genetics and Evolution 110
• Human Health and Diseases
• Human Physiology 242
• Human Reproduction
• Immune System
• Living World
• Locomotion and Movement
• Microbes in Human Welfare
• Mineral Nutrition
• Molecualr Basis of Inheritance
• Neural Coordination
• Organisms and Population
• Photosynthesis
• Plant Growth and Development
• Plant Kingdom
• Plant Physiology 261
• Principles and Processes
• Principles of Inheritance and Variation
• Reproduction 245
• Reproduction in Animals
• Reproduction in Flowering Plants
• Reproduction in Organisms
• Reproductive Health
• Respiration
• Structural Organisation in Animals
• Transport in Plants
• Trending 14

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