Lab Report For Plants And People Lab About Chemical Composition Cells
Excellent! You used distilled water as a negative control in this experiment. This verifies that any color reactions you saw were caused by the test solution used and not some other factor.
Excellent! You have used the starch solution as a positive control. This insures that your experimental proceedure, and reagents, can detect the presence of starch in an unknown sample.
Good technique! You used a graduated cylinder to insure that precise amounts of all reaction components were added to each experiment.
Good job! Good lab technique begins with avoiding the cross-contamination of your experiments.
Good technique! You have washed the mortar and pestle between uses. This prevents cross-contamination of samples.
Good job! You have realized that potatos contain more starch than onions.
SCORE
Test for Starch 100%
The Experiment 100%
Test both onion and potato for starch 100%
Use distilled water as a negative control 100%
Use starch as a positive control 100%
Use the graduated cylinder 100%
Put dirty stirring rods into wash tray 100%
Avoid contaminating the tubes 100%
Wash the mortar 100%
Realize that potatos contains more starch than onions 100%
Post-Lab Questions 100%
Identify the experimental samples that tested positive for starch 100%
Which of the following samples are likely to have a very dark color after the addition of Iodine reagent?
Did you know the answer: You said ‘Think so’.
You answered correctly:
• Starch Suspension • Potato Juice
Identify the controls in this experiment 100%
Which of the following was the negative control in the Test For Starch solution?
Did you know the answer: You said ‘Think so’.
You answered correctly:
Water
Recall the relative starch concentrations of the experimental solutions 100%
Arrange the following solutions in the correct order of highest starch concentration to lowest from top to bottom.
Did you know the answer: You said ‘Think so’.
You answered correctly:
• Potato solution • Onion Solution • Glucose Solution
