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a level biology required practical AQA

Write an introduction piece, and notes to help inform your conclusions, which are
written after the practical.
You should try to avoid simply quoting text from your research, and instead engage
with the information you find, and synthesise your own text to explain, predict and
suggest responses to these questions. You can use this document to complete this
work.

this is the work ive been set but im so lost as to what im supposed to write and what im meant to cite - like its just osmosis, its not that deep or complicated what do u want me to conclude about?
This is what ive written so far:
Overall, in concatenation, osmosis is the movement of water particles from an area of higher water potential to an area of lower water potential across a partially permeable membrane.
The highest possible water potential is 0 - pure water.
Increasing the solute concentration decreases the water potential and it becomes more negative.
This investigation has shown that ....
but im so confused and im meant to cite 5 references
any help or suggestions would be highly appreciated
tysm
Original post by Falistinprincess
Write an introduction piece, and notes to help inform your conclusions, which are
written after the practical.
You should try to avoid simply quoting text from your research, and instead engage
with the information you find, and synthesise your own text to explain, predict and
suggest responses to these questions. You can use this document to complete this
work.
this is the work ive been set but im so lost as to what im supposed to write and what im meant to cite - like its just osmosis, its not that deep or complicated what do u want me to conclude about?
This is what ive written so far:
Overall, in concatenation, osmosis is the movement of water particles from an area of higher water potential to an area of lower water potential across a partially permeable membrane.
The highest possible water potential is 0 - pure water.
Increasing the solute concentration decreases the water potential and it becomes more negative.
This investigation has shown that ....
but im so confused and im meant to cite 5 references
any help or suggestions would be highly appreciated
tysm

Since I do not know what equipment and chemical compound you used in practical, I cannot provide you with an adequate foreword.
I will write down the following scheme, which may give you some starting points for your report.

A bag filled with a sugar solution was dipped into a beaker of distilled water. The bag is made of a special fabric that allows it to do very interesting things. It is semi-permeable, which means that it acts like a filter, letting through only the tiny water molecules and not those of the solute which have much much larger dimensions.
It is a semi-permeable membrane and is similar to a net that lets some things in and keeps others out. Over time, the water molecules in the beaker will start to move into the bag to equalise the sugar concentration on both sides. This process is called osmosis.
The speed of osmosis depends on a number of factors:
Concentration gradient: The greater the difference in sugar concentration between the two sides of the bag (membrane), the faster the water flow will be.
Permeability of the membrane: The nature of the membrane and the diameter of its pores influence the speed of osmosis.
Temperature: A higher temperature increases the speed of movement of water molecules, accelerating osmosis.
Osmosis plays a crucial role in the absorption of water by plants and in maintaining fluid balance in our bodies.
Osmotic pressure is a colligative property associated with solutions.

Have a look here: Diffusion and Osmosis Lab Report Guidelines @mainly at the last chapter.
and there: Colligative Properties
Ciao,
The flag of Italy.pngSandro
My signature: "Regardless of where you may be, expressing gratitude is a universally cherished gesture."
(edited 2 months ago)
Original post by Nitrotoluene
Since I do not know what equipment and chemical compound you used in practical, I cannot provide you with an adequate foreword.
I will write down the following scheme, which may give you some starting points for your report.
A bag filled with a sugar solution was dipped into a beaker of distilled water. The bag is made of a special fabric that allows it to do very interesting things. It is semi-permeable, which means that it acts like a filter, letting through only the tiny water molecules and not those of the solute which have much much larger dimensions.
It is a semi-permeable membrane and is similar to a net that lets some things in and keeps others out. Over time, the water molecules in the beaker will start to move into the bag to equalise the sugar concentration on both sides. This process is called osmosis.
The speed of osmosis depends on a number of factors:
Concentration gradient: The greater the difference in sugar concentration between the two sides of the bag (membrane), the faster the water flow will be.
Permeability of the membrane: The nature of the membrane and the diameter of its pores influence the speed of osmosis.
Temperature: A higher temperature increases the speed of movement of water molecules, accelerating osmosis.
Osmosis plays a crucial role in the absorption of water by plants and in maintaining fluid balance in our bodies.
Osmotic pressure is a colligative property associated with solutions.
Have a look here: Diffusion and Osmosis Lab Report Guidelines @mainly at the last chapter.
and there: Colligative Properties
Ciao,
The flag of Italy.pngSandro
My signature: "Regardless of where you may be, expressing gratitude is a universally cherished gesture."

Thank you very much - this was the practical we followed but I'm not exactly sure what my introduction piece is meant to include:

1. Label six boiling tubes 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0 mol dm-3
sucrose.
2. Use the 1mol dm-3
sucrose solution and distilled water to make up 20cm3 of sucrose
solution of each of the following concentrations:
0.2 mol dm-3
0.4 mol dm-3
0.6 mol dm-3
0.8 mol dm-3
1.0 mol dm-3
3. Stand the boiling tubes containing the sucrose solutions in a thermostatic water bath set
at 30oC. Use a thermometer to check the temperatures in all boiling tubes reaches 30oC.
Record in a suitable table the temperature of each boiling tube.
4. Using the cork borer, cut six potato chips from your potato tuber. Remove any peel from
the chips. Cut each chip to the same length, and diameter.
5. Blot each potato chip dry using paper towel; ie roll each chip until it no longer wets the
paper towel and dab each end until dry. Do not squeeze the chips. Put each chip onto a
clean paper towel, or A4 plain paper, which you have numbered in the same way as the six
boiling tubes.
6. Weigh each potato chip, and record these initial masses in a suitable table.
7. At the water bath, set the stop clock to zero. Quickly transfer each potato chip from the
paper to it own boiling tube with the same number.
8. After 20 minutes, remove the chips from the boiling tubes. Blot dry as before. Then re-
weigh each chip. Record these final masses in your table.
9. Calculate the change in mass. Calculate the percentage change in mass. Show your
workings out. Record these values in a suitable table.
10. Plot a graph of your processed data and use this to determine the concentration of
sucrose which has the same water potential as the potato tuber cells.
Original post by Falistinprincess
Thank you very much - this was the practical we followed but I'm not exactly sure what my introduction piece is meant to include:
1. Label six boiling tubes 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0 mol dm-3
sucrose.
2. Use the 1mol dm-3
sucrose solution and distilled water to make up 20cm3 of sucrose
solution of each of the following concentrations:
0.2 mol dm-3
0.4 mol dm-3
0.6 mol dm-3
0.8 mol dm-3
1.0 mol dm-3
3. Stand the boiling tubes containing the sucrose solutions in a thermostatic water bath set
at 30oC. Use a thermometer to check the temperatures in all boiling tubes reaches 30oC.
Record in a suitable table the temperature of each boiling tube.
4. Using the cork borer, cut six potato chips from your potato tuber. Remove any peel from
the chips. Cut each chip to the same length, and diameter.
5. Blot each potato chip dry using paper towel; ie roll each chip until it no longer wets the
paper towel and dab each end until dry. Do not squeeze the chips. Put each chip onto a
clean paper towel, or A4 plain paper, which you have numbered in the same way as the six
boiling tubes.
6. Weigh each potato chip, and record these initial masses in a suitable table.
7. At the water bath, set the stop clock to zero. Quickly transfer each potato chip from the
paper to it own boiling tube with the same number.
8. After 20 minutes, remove the chips from the boiling tubes. Blot dry as before. Then re-
weigh each chip. Record these final masses in your table.
9. Calculate the change in mass. Calculate the percentage change in mass. Show your
workings out. Record these values in a suitable table.
10. Plot a graph of your processed data and use this to determine the concentration of
sucrose which has the same water potential as the potato tuber cells.

Hello!
As fluent as I am in English, I apologise if you find my writing lacking. You know, the language barrier is there.
Personally, I would write the report based on the suggestions below.
Introduction piece:
In this experiment, we studied the behaviour of plant cells vs. different concentrations of sucrose solutions. We observed how sucrose solutions affect potatoes.
Description of the method:
In general, the experiment consists of preparing sucrose solutions, dipping potato slices into them, and measuring changes in their mass.
Experiment plan:
We prepared solutions with different concentrations of sucrose, put potato slices in them, and measured their mass before and after the experiment.
To carry out this experiment, we immersed potato slices in solutions with varying sugar concentrations, spanning from plain water to highly concentrated sucrose solutions. We weighed the potato slices before and after immersing them in the solution for 20 minutes to record their mass changes.
Hypothesis: We believed that with an increase in the concentration of sucrose, the mass of potato slices will decrease, as water will leave the potato cells.
The purpose of the study:
We aimed to investigate how the mass of potato slices changes in response to varying sucrose concentrations.
To determine the sucrose concentration at which potato cells achieve equilibrium, we needed to investigate the mass changes of potato slices in varying sucrose concentrations.
Description of osmosis: This is the process of moving water through semipermeable membranes, which depends on the concentration of solutes. We assumed that when using a more concentrated solution (with a high sugar content), the mass of potato slices will decrease, as water will escape from the potato cells.

1.

There might be some repetitions in the text, be careful.

2.

Also, pay attention to the verb tenses that I have used.

Ciao,
The flag of Italy.pngSandro
My signature: "Regardless of where you may be, expressing gratitude is a universally cherished gesture."
Original post by Nitrotoluene
Hello!
As fluent as I am in English, I apologise if you find my writing lacking. You know, the language barrier is there.
Personally, I would write the report based on the suggestions below.
Introduction piece:
In this experiment, we studied the behaviour of plant cells vs. different concentrations of sucrose solutions. We observed how sucrose solutions affect potatoes.
Description of the method:
In general, the experiment consists of preparing sucrose solutions, dipping potato slices into them, and measuring changes in their mass.
Experiment plan:
We prepared solutions with different concentrations of sucrose, put potato slices in them, and measured their mass before and after the experiment.
To carry out this experiment, we immersed potato slices in solutions with varying sugar concentrations, spanning from plain water to highly concentrated sucrose solutions. We weighed the potato slices before and after immersing them in the solution for 20 minutes to record their mass changes.
Hypothesis: We believed that with an increase in the concentration of sucrose, the mass of potato slices will decrease, as water will leave the potato cells.
The purpose of the study:
We aimed to investigate how the mass of potato slices changes in response to varying sucrose concentrations.
To determine the sucrose concentration at which potato cells achieve equilibrium, we needed to investigate the mass changes of potato slices in varying sucrose concentrations.
Description of osmosis: This is the process of moving water through semipermeable membranes, which depends on the concentration of solutes. We assumed that when using a more concentrated solution (with a high sugar content), the mass of potato slices will decrease, as water will escape from the potato cells.

1.

There might be some repetitions in the text, be careful.

2.

Also, pay attention to the verb tenses that I have used.

Ciao,
The flag of Italy.pngSandro
My signature: "Regardless of where you may be, expressing gratitude is a universally cherished gesture."

Thank you very much 🙂
This is very helpful and I appreciate it a lot!

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