Plant Tropisms and Hormones Lab Student Handout
Student Name: _____________________________________ Date: ________________
Directions: Use the information in the “Plant Tropisms and Hormones Lab” lesson to help you complete
this handout. Once you have completed this handout, save it to your device, and upload it to the
appropriate assignment.
Use the video clips and scenarios from the lesson to help you answer the following questions.
Part 1: Plant Tropisms (5pts each = 40pts)
1. Phototropism is a plant’s response to _____________________________________.
2. Geotropism is a plant’s response to _______________________________________.
3. Hydrotropism is a plant’s response to _____________________________________.
4. Shoots will always grow upward due to ________________ ___________________.
5. Plants will also always grow towards the source of light energy due to ___________
______________.
6. The roots of plants grow down into the ground because of ______________
________________.
7. ________________ ___________________ causes the roots of plants to grow towards water.
8. The amount of ________________ is affected by external conditions and regulates plant
growth.
Part 2: Lab-based Scenarios (6pts each = 30pts)
9. Make a hypothesis on the direction each plant will grow.
10. What type of tropism is most likely being tested based upon the lab setup and why?
11. What is your observation of the roots for each plant in the image?
12. What type of tropism is most likely being tested based upon the lab setup and why?
13. Under normal conditions, the roots of plants grow downward. This illustrates what type of
tropism?
Part 3: Plant Hormones (5pts each = 30pts)
14. ________________________are chemical messengers that can deliver signal to various
locations.
15. Removing a plant’s stem tip reduces the amount of __________________, a plant hormone
responsible for aiding the plant in exhibiting positive phototropism.
16. Plants require the plant hormone ______________________ in order to germinate.
17. __________________works alongside other plant hormones to aid in the development of
shoots and the abscission of leaves, flowers, and fruits.
18. The plant hormone ____________________ is also especially important to plants in that it is not
only responsible for helping fruits ripen, but also aids shoots in pushes upward through the soil
before blooming.
19. Plants use ______________________to help prevent dehydration by leaking this hormone into
the chloroplast to signal the closing of the stomata.