2 repeat steps 22 and 23 with another cotton ball

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2.Repeat steps 22 and 23 with another cotton ball piece and the second test tube. At thispoint, the cotton balls will secure the seeds in the end of the test tubes, when turned over.3.Fill the 100-ml glass beaker with approximately 50 ml of distilled water.4.Use the scissors to cut open the yellow food coloring then add 2 drops of food coloring intothe distilled water.Note: The food coloring will help you make observations about the water levels of thetest tubes. The food coloring does not influence the experimental results.1.Swirl the beaker to mix the food coloring into the water.2.Pick up 1 of the 2 test tubes and turn it over and place it into the yellow-colored distilledwater. The tube should be straight up and down, not tilted. Use the clear tape to hold thetest tube up against the side of the glass beaker, leaving approximately 5 mm of distancebetween the bottom of the beaker and the opening of the test tube. See Figure 16.Note: It is helpful to first tape the back of the test tube to the outside of the beaker, andthen tape the rest of the tube to the beaker.1.Repeat step 28 for the second test tube, placing the 2 test tubes next to one another. SeeFigure 16.Figure 16.Placing tubes in beaker.A.Tubes taped to the beaker.B.5 mm space between the openingof the test tubes and the bottom of the beaker.1.Gather the desk lamp with the 100-watt incandescent light bulb, and place the lampapproximately 1 foot away from the beakers with the light shining directly at the seeds. Thelight source is used to keep the seeds warm so they will respire more quickly. See Figure 17.Figure 17.Light shining on the beaker and seeds.1.Using the distance markings on the test tubes, measure the distance of the water in each ofthe tubes, as shown in Figure 18.
Figure 18.Reading from the water line. Note the meniscus of the water.1.Record the distance of the water in each tube (0 cm to 6 cm) inData Table 1for “0minutes”.2.Record any additional observations at “0 minutes” inData Table 1. Observations mayinclude: moisture forming, bubbles forming, condensation in the tube, etc.3.Repeat steps 32 and 33 every 10 minutes for 2 hours.4.As you are waiting to record your second set of observations, create a hypothesis (aneducated guess), about your test and record inData Table 1. For example, a hypothesismight state, “The water level of test tube _____ will be higher than the water level in testtube _____ because _____.”Cleanup:Dispose of any remaining 0.5M NaOH and yellow food coloring down the drain with copiousamounts of running water.Place all used pipets in the trash.When all data has been collected, wash and dry all materials (including the Petri dishes) andreturn the clean materials to the lab kit for future use.Exercise 1 - Questions1. Were the seeds in the “N” tube undergoing respiration? Use your results in Data Table 1to support your answer. Do your results support your hypothesis?2. Were the seeds in the “G” tube undergoing respiration? Use your results in Data Table 1to support your answer. Do your results support your hypothesis?3. Describe the relationship between photosynthesis and respiration.4. Review the equations below used to describe photosynthesis and respiration (as provided

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Term
Winter
Professor
P. Pepe
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