• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Osmosis Internal Assessment (Biology)

Extracts from this document...

Introduction

BIOLOGY INTERNAL ASSESSMENT STANDARD LEVEL OSMOSIS OSMOSIS IN POTATO STRIPS i. Aim To investigate the change in the mass of potato strips as a result of the process of osmosis in potato strips over varying periods of time. ii. Research Question How does time affect the mass of potato strips (measured in grams) when immersed in distilled water (H20) over a period of five hours at one hour intervals: 1 hour, 2 hours, 3 hours, 4 hours, and 5 hours? iii. Introduction Osmosis is the passive movement of water molecules from a region of high water concentration to a region of lower water concentration (lower solute concentration to higher solute concentration), across a partially permeable membrane.1 The plasma membrane is selectively permeable, and it controls the movement of substances in and out of cells, but water is able to move freely in and out of the cell, allowing osmosis to occur.2 Potato cells have selectively permeable membranes and therefore can be used to show the process of osmosis. As plant cells generally have a higher solute concentration than their surroundings (lower water concentration), when immersed in H20, the potato strips will be surrounded by a region of high water concentration since water has a solute concentration of 0.3 This would mean that the distilled water is hypotonic whereby it has a higher concentration of water than the potato cells, causing water to flow from the area of higher water concentration (water solution) ...read more.

Middle

Dispose of all used material appropriately. vii. Results Table 1. Initial and final mass of the potato strips after immersion in distilled water () over a period of five hours at one hour intervals Duration given for osmosis to occur (hours ? 1min) Initial and final mass of potato strips ?0.1g Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Initial Mass Final Mass Initial Mass Final Mass Initial Mass Final Mass Initial Mass Final Mass Initial Mass Final Mass 1.0 3.0 3.0 3.0 3.0 3.0 3.1 3.0 3.2 3.0 3.0 2.0 3.0 3.2 3.0 3.3 3.0 3.3 3.0 3.2 3.0 3.1 3.0 3.0 3.4 3.0 3.4 3.0 3.6 3.0 3.5 3.0 3.4 4.0 3.0 3.5 3.0 3.6 3.0 3.5 3.0 3.7 3.0 3.7 5.0 3.0 3.6 3.0 3.6 3.0 3.6 3.0 3.7 3.0 3.6 *Note that the initial mass of all the potato strips are the same Table 2. Mean, standard deviation, and 33.33% of the mean for the final mass of potato strips immersed in distilled water () Duration given for osmosis to occur (hours ? 1min) Mean, S.D, and 33.33% of mean of final mass of potato strips ?0.1g Mean S.D. 33.33% of mean 1.0 3.1 0.09 1.02 2.0 3.3 0.08 1.09 3.0 3.5 0.09 1.16 4.0 3.6 0.10 1.19 5.0 3.6 0.04 1.19 *As the Standard Deviation is less than 33.33% of the mean for all the values of final mass of the potato strips, it can be seen that these mean values are accurate. ...read more.

Conclusion

Way in which mass was measured The mass of the potato strips were recorded using an electronic weighing scale up to only one decimal place, thus resulting in minimal differences in data collection, making conclusions more general and vague. Using a weighing scale with up to two decimal places will allow the data collected to be more accurate. Frequency of data collection* The mass of the potato strips were recorded after immersion in distilled water for 1 hour, 2 hours, 3 hours, 4 hours, and 5 hours, meaning large gaps between the data points, causing conclusions to be less accurate as the data was less reliable, and trends were more general and rather vague. Collection of data should occur at half an hour intervals over a period of six hours, providing ample data to make detailed conclusions. 1 Andrew Allot. IB Study Guide: Biology Standard and Higher Level (2nd edition). UK: Oxford University Press, 2007. 2 Alberts B, Johnson A, Lewis J. Molecular Biology of the Cell (4th edition). New York: Garland Science, 2002. 3 M B V Roberts. Biology, A functional approach (4th edition). UK: Thomson Nelson and Sons Ltd, 1986. 4 Ibid. 5 Regina Bailey. "Diffusion and Passive Transport" About.com Guide. Biology. 11 May 2011. <http://biology.about.com/od/cellularprocesses/ss/diffusion_3.htm>. 6 Alberts B, Johnson A, Lewis J. Molecular Biology of the Cell (4th edition). New York: Garland Science, 2002. ?? ?? ?? ?? Biology Internal Assessment - Osmosis Page 1 of 11 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology section.

Found what you're looking for?

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

Here's what a teacher thought of this essay

4 star(s)

****
An excellent investigation into the effect of osmosis on the potato chips.
The introduction gave a good scientific foundation for the investigation and was well laid out with relevant information.
The method was very thorough and gave enough detail for the investigation to be repeated.
One limitation to the experiment was the independent variable. By choosing time it left the scientific analysis a little basic as osmosis continuing to happen over time is rather obvious.
The analysis of the data was excellent. The graphs clearly shown the general trend of the results.

Marked by teacher Jon Borrell 22/05/2013

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

See related essaysSee related essays

Related International Baccalaureate Biology essays

  1. Marked by a teacher

    The effect of Pectinase Concentraton on the production of apple juice

    So by using a grater (included in the apparatus), the size/shape of the apples will be kept as similar as possible. Apparatus: Appropriate apparatus needs to be used so fewer errors will be made also measuring equipment should be regularly check so the results will be as accurate as possible.

  2. Biology Lab Report-Osmosis

    the potato cell, then water from the potato cell will move out into the solution, through the semi-permeable membrane by osmosis. This means that each cell of the potato chip will decrease in size and mass as water leaves the cell.

  1. Biology HL IA - Transpiration lab report

    Then, approximately one third of all leaves were cut, cutting places were immediately covered with nail polish. After 10 minutes of rest records were started to be taken every 5 minutes for a period of 25 minutes. Then, the same procedure was made with second third and last third of all leaves until the plant had no leaves at all.

  2. Potato and Sweet Potato Water Potential in Different Sugar Solutions

    10% 2. 17.6% 3. -0.66% 4. -5.66% 5. -11.66% - For sweet potato: 1. 17.3% 2. 15% 3. 4% 4. -7% 5. -10.66% Graph 1 (Potato): Graph 2 (Sweet Potato): Conclusion: What was found was that the concentration of the sugar solution increased while the weight of the potato decreased and this therefore, supports the hypothesis.

  1. Biology HL IA - Photosynthesis of elodea lab report

    The bubbles that collected on the highest point of photosynthometer were pulled to the measuring pipette by pulling the plunge of syringe gently. The volume of the gas bubbles released was recorded (mL) and experiment was repeated 4 more times using the same position of lamp in order to obtain reliable results.

  2. affect of age on reaction time

    are still new and unharmed therefore reacting quickly to a stimulus. The second age group which was between the ages 20 and 30 years scored the second best average reaction time just as I said in my hypothesis. The difference in the average reaction time between the first and second age group is very minimum (1 cm).

  1. To investigate the amount of protein present in different types of milk by measuring ...

    For the protein yield in nutrition panels, the mass of protein in goat milk is greater than the mass of protein in soya milk whereas the mass of protein in goat milk is smaller than the mass of protein in soya milk in my result.

  2. To investigate how aerobic exercise affects the heart rate

    of the results obtained are and to measure how close it is to the average mean. The less the spread of the value from the mean, the more reliable the results are. In addition, by repeating the experiment for all samples, results obtained will be more accurate as it allows

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