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

Finding the isotonic point for potato tissue

Extracts from this document...


Noémie Pauwels BIOLOGY COURSE WORK Finding the isotonic point for potato tissue 1. Raw results table Concentration of sucrose solution (M) Mass of potato sticks (g ±0.01g) Before soaking in sucrose solution After soaking in sucrose solution for 30 min. 0.0 2.90 3.05 2.90 3.04 2.86 3.05 2.88 3.01 2.80 2.98 2.87 3.01 0.2 2.96 3.01 2.97 3.03 2.90 3.04 2.91 2.98 2.80 2.86 2.87 2.96 0.4 2.90 2.84 2.87 2.83 2.76 2.73 2.84 2.77 2.83 2.79 2.90 2.81 0.6 2.97 2.81 2.98 2.74 2.99 2.78 2.91 2.80 2.97 2.79 3.00 2.77 0.8 2.81 2.61 2.88 2.63 2.87 2.61 2.90 2.62 2.91 2.64 2.92 2.68 1.0 2.88 2.69 2.88 2.62 2.92 2.64 2.89 2.61 2.90 2.61 2.88 2.62 1. Processed results table Concentration of sucrose solution (M) Mass of potato sticks (g ±0.01g) Before soaking in sucrose solution Before soaking in sucrose solution Difference Percentage change in mass of potato sticks (%) Mean percentage change in mass of potato sticks (%) Standard deviation of percentage change in mass of potato sticks (%) 0.0 2.90 3.05 + 0.15 2.90 3.04 + 0.14 2.86 3.05 + 0.19 2.88 3.01 + 0.13 2.80 2.98 + 0.18 2.87 3.01 + 0.14 + 5.17 + 4.83 + 6.64 + 4.51 + 6.43 + 4.88 + 5.41 0.82 0.2 2.96 ...read more.


This means that the rate of osmosis would be faster and that the potato sticks would increase or decrease in mass faster. TYPE OF ERROR: This is a procedural and significantly major error because the temperature is not even measured. IMPROVEMENT: Heat the sucrose solution for 20 minutes in a boiling tube in a water bath set to 25 °C and check the temperature of the water with a thermometer before adding the potato pieces. 1. PROBLEM: Difference of potato sticks EXPLANATION: The cells of the potato sticks have different concentrations of solutes because more than one potato was needed to obtain enough samples of potato. Cells with a greater concentration of solutes would absorb more water and gain more mass when soaked in 0.0 M sucrose solution. The potato sticks are not from the same potato. This means that the cells have a different solute concentration, a different concentration gradient and so the rate of reaction would be different. TYPE OF ERROR: This is a procedural and significantly major error. This factor limits the reliability of the method. IMPROVEMENT: Check the solute concentration of the potato cells and adapt the concentration of the sucrose solution to reach a same concentration gradient. ...read more.


From the graph, we can conclude that the more hypertonic the potato sticks are to the sucrose solution, the more the potato sticks will increase in mass. On the other side, when the potato sticks are more hypotonic to the sucrose solution, the mass of the potato sticks will decrease more. 1. Glossary - concentration gradient : a gradual change in the concentration of solutes in a solution - cytoplasm : living part of the cell, bound by the plasma membrane, excluding the nucleus. - dilute solution : a solution that contains a small concentration of solute.. - hypertonic solution : a more concentrated solution (one with a less negative water potential) than the cell solution. - hypotonic solution : a less concentrated solution (one with a more negative water potential) than the cell solution. - isotonic : being of the same osmotic concentration and therefore of the same water potential. - kinetic energy : energy in movement. - micrometer : A device for measuring very small distances - osmosis : passive movement of free water particles from a more dilute solution to a more concentrated solution across a partially permeable membrane along a concentration gradient. - plasmolysis : withdrawal of water from a plant cell by osmosis. - solute : a substance dissolved in another substance. - turgid : having high internal pressure ...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

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


    3 star(s)

    Place a blue coloured pin in 5 potato chips, push the pins to the middle of the chips. 7) Repeat the previous process with 5 more chips using red pins. Then repeat again with 5 more potato chips using white pins.

  2. The effect of concentration of sucrose solution on the osmosis in potato

    Try to make the mass and length as even as possible. Control Experiment The control experiment will be carrying out distilled water used in place of the sucrose solution. 1.3 Experimental Method Materials Apparatus Required Quantity * Cutting tile 1 * Scalpel 1 * 30 cm3Test tube 25 * Different concentration of sucrose solution (0%, 5%, 10%, 15% and 20%)

  1. Isotonic Point of Potatoes

    Mass Before (g) (+/- 0.01 g) Mass After(g) (+/- 0.01 g) Length Before (+/- 0.05 cm) (cm) Length After (+/- 0.05 cm) (cm) Sample 1 1.78 1.76 3.00 2.95 Sample 2 1.75 1.74 3.00 3.00 Sample 3 1.67 1.70 3.00 3.00 Sample 4 1.82 1.85 3.00 3.00 Sample 5 1.75

  2. Osmosis Experiment. This experiment is to consider how salinity influences osmosis in potato cells.

    TABLE 1: Practical Investigations Variables Independent Variable * The salinity concentrations in the water * (0%, 0.2%, 0.4%, 0.6%, 0.8%) Dependent Variable * Mass of the potato cubes (compare the mass of the potato cube before and after 20 hours)

  1. Investigating isotonic point of a potato

    Using the cork borers and cut out 15 chips of roughly the same size, length and thickness. Use the scalpel to cut the chips into equal length. So that it is a fair test. 3) Weigh each chip using the weighing scale and record the reading, then take the average of the results.

  2. Lung Capacity Fitness Level

    Ensure that participants are relaxed and not tense. Sitting upright will prevent any blockages of airways, enabling accurate results to be recorded. Technique of holding spirometer Spirometer should be placed in the palm (one hand pinching nose, one hand holding the spirometer) of the participant. The mouthpiece of the spirometer should be positioned directly in front of the participant's mouth.

  1. Investigation of osmosis in potato strips by measuring the length of the strips after ...

    from time of dropping the strips into the beakers. After 30 minutes. Each sample was drained off and measured using the same ruler again to see if the length of the potato strips has changed. Method for recording the raw data was to make a table and to write up any other observations Data collection and processing: Raw data

  2. How does changing the percentage of sucrose added to yeast affect the rate of ...

    ?These channels are the way in which medium-sized polar molecules like glucose may pass into the cell. The number of protein channels available limits the rate of facilitated transport? 1 this causes an increase in sucrose concentration to have less of an effect at higher sucrose concentrations.

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