• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3
4. 4
4
5. 5
5
6. 6
6
7. 7
7
8. 8
8
9. 9
9
10. 10
10
11. 11
11
12. 12
12
13. 13
13
14. 14
14
15. 15
15
16. 16
16

# How Does Osmosis Affect Plant Cells?

Extracts from this document...

Introduction

Aim: The aim of the experiment is to find out how the concentration of the solution will affect the rate at which osmosis occurs. I will use this as a trial run to find out which concentrations and at what time is best to leave the cuttings for the greatest change in mass to occur. Apparatus: * 2 potatoes * 2 250ml beakers * 25ml of sugar * top pan balance * no. 9 core borer * knife * 375ml of distilled water * tablespoon * stopwatch Method: 1. Collect the equipment. 2. Add 125ml of water and 25ml of sugar in one beaker and 150ml of distilled water in the other. 3. Using the size 7 core borer carefully cut 10 equal 3cm strips out of the potato. 4. Using the scalpel cut the cuttings to 5 grams and 3cm stripes, making them as close to one another as possible. 5. Mix the solution with the tablespoon, then add 5 pieces of potato to each beaker, while timing the length of time they are in for to the set times. 6. At every set time measure the length and mass of all the potato cuttings and put it back into the beaker. 7. Record the results into a coherent table. Fair Test: To make my experiment a fair test I will keep the potato cutting at the same length and mass. I will use the same size borer, no. 7, throughout. My cuttings will be taken from the same type of potato and will contain no peel. The volume of the two liquids must also be kept equal. Table of Results: SUGAR SOLUTION (started at 10:45am) TOTAL MASS (grams) TOTAL LENGTH (cm) TIME TAKEN OUT BEFORE AFTER DIFFERENCE BEFORE AFTER DIFFERENCE 30mins 5 4.82 -0.18 3 3.0 0 1h 30 5 4.37 -0.63 3 2.7 -0.3 4h 45 5 4.02 -0.98 3 2.4 -0.6 24h 30 5 4.15 -0.85 3 2.2 -0.8 28h 45 5 3.96 -1.04 3 2.2 -0.8 WATER SOLUTION (started at 10:45am) ...read more.

Middle

Whatever the set time is they must all stay in the same time. Type of plant cell There are different plant cells within a plant. Some plant cells contain more water than others, they all have different concentrations of cell sap therefore the rate of osmosis varies from cell to cell. Use the same potato, one potato and remember to remove the peel, as it contains different cells to the rest of the storage cells that make up a potato. Prediction: I predict that the more dilute the solution (the higher the concentration of water) is, the greater the mass of the potato cutting will be after the set time. The higher the concentration of sugar in the solution is, the more water loss there will be and therefore the lighter the cutting will become. I believe osmosis will occur at a greater rate within the cutting, when there is a greater amount of water than sugar in the solution. This means the cuttings that are put into a higher concentration of water will end up with a larger mass than those put into a higher concentration of sugar. Osmosis is the movement of water from a weaker solution into a stronger solution through a semi-permeable membrane while the other solutions are blocked and unable to pass through the membrane. The water will move from a higher concentration of water to a lower concentration of water through a semi-permeable membrane. For example if there was one side of a semi-permeable membrane with 70% water and another side with 40% water, the side with the greater percentage of water, the 70% side would flow from its higher concentration to the lower concentration to help even out the concentrations to an isotonic point, were both sides will be of equal strength. The water molecules are far smaller than the sugar molecules are therefore they are able to fit through the membrane to the lower concentration. ...read more.

Conclusion

The rate of osmosis would vary from cell to cell and it would be interesting to compare the results and find any links or connections as t o why there are comparisons. Different types of potato (e.g. grown from different areas of the world, under different environments) - I would do a similar investigation as this one only using potato from different environments and climates. Once I find the isotonic solution of the different potatoes I could compare the rate of osmosis within the different cuttings (e.g. I could compare the potato cuttings from a hot climate and from a cold climate and investigate whether there are any connections or patterns with the rate of which osmosis occurs and the environment in which the potato is grown in). Different plants/vegetables (e.g. apple, carrot, etc.) - I could investigate if there is a difference in the rate of osmosis within the different plant/vegetable cells. There would definitely be varying results with the different plants/vegetables, as some are root vegetables (e.g. carrot, potato), some are ground vegetables (e.g. peas) and some are open vegetables (e.g. apples, pears) and each have a different function, for example the function of a root vegetables is to hold all of the nutrients needed to promote the potato seedling to grow without sunlight. Different dimensions and surface areas of a cutting - In the experiment I have just completed I used cuttings of equal dimensions and surface areas, but instead I could very this slightly and vary the dimensions of the cutting which would therefore very the surface area. It would be interesting to see if there was a difference in the rate of osmosis when several cuttings of the same mass, but different dimensions were investigated. My results were fairly accurate and even when they were plotted into a graph I cannot see any obvious anomalies. GCSE Biology Coursework - How Does Osmosis Affect Plant Cells? (Preliminary Work) 5 GCSE Biology Coursework - How Does Osmosis Affect Plant Cells? (Planning) 16 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Life Processes & Cells section.

## Found what you're looking for?

• Start learning 29% faster today
• 150,000+ documents available
• Just £6.99 a month

Not the one? Search for your essay title...
• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month

# Related GCSE Life Processes & Cells essays

1. ## How does the concentration of a sucrose solution affect the rate of Osmosis in ...

5 star(s)

The graph will start to level out after Point B as the cells have not lost all of their water, but they have lost all the water that they can, so theoretically, the mass will not decrease below a certain point.

2. ## Investigating the effect of sucrose concentration on osmosis in potato cells

4 star(s)

I will look at the first point first. This has certainly been proved to be correct - the highest gain in mass (excluding obvious anomalies) was found in repeats 1 and 3 of 0.0 M solution - both 6.94%, as shown in my results and graph in light blue.

1. ## The aim of this investigation is to find out how the concentration of the ...

4 star(s)

Therefore, there is more opportunity for osmosis to occur quickly. Concentration The higher the water concentration of a solution, the more osmosis occurs. This is because, as shown above, water molecules always move from an area where there is more of them to an area where there is less of

2. ## To investigate how varying the concentration of sucrose solutions affects the rate of osmosis ...

3 star(s)

Books I have referred to in order to gain help in planning a safe and fair investigation: 1. Biological Science 2 2. Advanced Heinemann Biology by Ann Fullock 3. Advanced Biology by Michael Robert Collins Biology by Marcus Barbos Section 2: Obtaining evidence Actual experiment: When I conducted my actual

1. ## Find the rate of osmosis in different vegetables (Carrot, Potato, Swede, Parsnip and Sweet ...

3 star(s)

Results table for mass change: Vegetable Exp. 1 mass before (g) Exp. 1 mass after (g) Exp. 2 mass before (g) Exp. 2 mass after (g) Potato Swede Sweet Potato Carrot Parsnip Vegetable Exp. 1 mass change (g) Exp. 2 mass change (g)

2. ## Efeects of Osmosis in Plant Cells

* Units of Measurement - moles/litre (m/l) * Cling Film (used as a seal) Diagram of My Preliminary Experiment Preliminary Experiment Method For my preliminary experiment I will prepare five visking tubing bags, which will each have 10ml of sucrose solution inside. The solution in each visking bag will have the same volume and concentration of sucrose.

1. ## Investigating the cellular water potential of potato cells.

This will also allow for any anomalies within my experiments and so make my results more reliable. Apart from the concentrations of the sucrose solutions that I will be using, there are many other variables that I must consider within this experiment, which could affect the results that I obtain.

2. ## Osmosis is defined as 'the movement of water molecules from an area of high ...

Stopping the clock, taking them out and measuring it all in less than a minute us quite impossible because we lack the number of balances. And there are obviously too many sets to go through at such a fast time.

• Over 160,000 pieces
of student written work
• Annotated by
experienced teachers
• Ideas and feedback to