Connecting Concepts
Use Science Graphics
Recall that growth responses of plants to external stimuli are called tropisms. A tropism is positive if the affected plant part grows toward the stimulus. The response is negative if the plant part grows away from the stimulus. The experiment shown below was intended to test the effect of gravitropism on plant growth. The conclusion drawn from the experiment was that the plant stems grow upward due to negative gravitropism. Use the diagram to answer questions 30–33.
Interpret Visuals Describe the three experimental setups and the result of each.
Form a Hypothesis What was the probable hypothesis for this experiment?
Interpret Visuals From the experimental setups shown, was the hypothesis successfully tested? Explain.
Evaluate and Revise Indicate what kinds of changes you would make to improve this experimental design.
Write About Science
Explanation Sometimes, people grow houseplants on a windowsill. Books on houseplants often advise giving the plants a one-quarter turn every other week. Write a paragraph explaining why turning the plant is a good idea. (Hint: Be sure to include an explanation of tropisms in your answer.)
Assess the
Explain why flowers are the key to the evolutionary success of the angiosperms.
Analyzing Data
In a laboratory experiment, fruits from five different kinds of trees were dropped from a height of 4 meters, and the time it took them to reach the ground was measured. Assume that for every second a fruit falls, it is carried 1.5 meters away from the parent tree.
Draw Conclusions Based on the data and the illustrations of the fruit structures, which of the following is the most reasonable conclusion?
Winged seeds carry more nutrition for the growing embryo than do seeds without wings.
Wind is not very effective in carrying seeds away from the parent plant.
Acorns are more likely to germinate if they fall close to the parent plant.
Red oak and hickory depend on factors other than wind to achieve dispersal.
Analyze Data Given the same wind, which fruit type is most likely to be carried farthest from the parent tree?
Red oak
Silver maple
Norway maple
White ash
Table of Contents
- Formulas and Equations
- Applying Formulas and Equations
- Mean, Median, and Mode
- Estimation
- Using Measurements in Calculations
- Effects of Measurement Errors
- Accuracy
- Precision
- Comparing Accuracy and Precision
- Significant Figures
- Calculating With Significant Figures
- Scientific Notation
- Calculating With Scientific Notation
- Dimensional Analysis
- Applying Dimensional Analysis