6 allow the bags to sit for one hour bi205

6. Allow the bags to sit for one hour.

BI205: Introductory Biology II Week 4 Lab Page 6 of 8
7. Using the examples provided in the “BI20x Hypotheses & Predictions Guide” available in
Canvas, develop a hypothesis for your experiment. Include your hypothesis, along with
supporting scientific reasoning in the space below.
8. Using the examples provided in the “BI20x Hypotheses & Predictions Guide” available in
Canvas, develop predictions for whether water will flow into or out of each dialysis bag.
9. Now that treatments have soaked for an hour, re-measure the weights of each dialysis bag
using the digital scale. Record your measurements in the following table.
10. Calculate the change in weight for each bag. If the weight of the bag increased during the
experiment, put a “+” symbol in front of the number. If the weight of the bag decreased
during the experiment, put a “-“ symbol in front of the number. Record your calculations in
the following table.
Treatment Band Color WEIGHT CHANGE
3% sucrose Yellow - 0.01
15% sucrose Red + 0.03
30% sucrose Blue 0
Sugar free pop Green -0.02
Regular pop White +0.01
You are now done with the experiment. Proceed to Part III where you will demonstrate what you
have learned by answering a series of related questions.

BI205: Introductory Biology II Week 4 Lab Page 7 of 8
Part III: Lessons Learned
1. In this experiment, what was the independent variable? The dependent variable? Refer to
your Week 4 readings in the Writing for Biology text for clarification.