Lesson Worksheet: Hormones in Plants Biology
In this worksheet, we will practice describing the importance of auxins in plant growth and development and explaining the action of auxin in plant phototropism.
Q1:
In light of your study of auxins, which of the following would most likely be their main commercial use in agriculture?
- AInhibiting the growth of roots so that crops would need a smaller amount of water
- BProtecting the crops from birds and pest insects due to their toxic effect
- CStimulating the vertical growth and the development of different parts of the plant
- DDirecting the growth of the shoots of crop plants towards the sunlight to track the direction of the Sun
Q2:
Where in a plant are the highest concentrations of auxins found?
- AIn the guard cells of the stomata
- BIn the wall of the xylem
- CIn the tip of the stem
- DIn the pollen of the flowers
Q3:
The diagram provided shows the effect of IAA (a type of auxin) on the growth of a plant shoot. What effect does IAA have on the cells in the shoot?
- AIAA helps break down dead cells in the stem.
- BIAA encourages cell elongation.
- CIAA prevents cell growth.
- DIAA stimulates cell differentiation.
Q4:
In high concentrations, what effect do auxins have on cells in the root?
- AAuxins inhibit cell elongation and growth in the root.
- BAuxins stimulate cell elongation and growth in the root.
- CAuxins have no effect on the growth of root cells.
Q5:
In plants, the high concentrations of auxins affect the cells of the root by their growth and affect the cells of the stem by their growth.
- Ainhibiting, slowing
- Bincreasing, also increasing
- Cinhibiting, increasing
- Dincreasing, inhibiting
Q6:
The provided diagram shows a coleoptile undergoing light tropism.
If we took a tissue sample from side A and side B to quantify the concentration of auxins in each side, what should we expect to find?
- AThe samples from both sides will have equal levels of auxins.
- BThe samples from both sides will have no auxins at all.
- CThe sample from side A will have more auxins than that from side B.
- DThe sample from side A will have less auxins than that from side B.
Q7:
Shoots and roots respond differently to the same concentrations of auxins. Which of the following statements correctly justifies the statement of the question?
- AThe same concentration of auxins might stimulate the elongation of root cells while having no effect on shoot cells.
- BLow concentrations of auxins stimulate the growth of both the stem and the root but in different directions.
- CHigh concentrations of auxins stimulate the growth of both the stem and the root but in different directions.
- DThe same concentration of auxins might stimulate the elongation of shoot cells while having no effect on root cells.
Q8:
If the seedling in the diagram is to perform a typical phototropism, on which sides of the stem and root should the concentration of auxins be higher?
- AOn the sides of both the stem and the root away from the light
- BOn the sides of both the stem and the root facing the light
- COn the side of the stem away from the light and on the side of the root facing the light
- DOn the side of the stem facing the light and on the side of the root away from the light
Q9:
Which of the following is correct about auxin production during phototropism?
- AAuxins are produced in the illuminated side and diffuse to the shaded side of the stem.
- BAuxins are produced in the stem tip and accumulate on the shaded side.
- CAuxins are produced in the shaded side of the stem.
- DAuxins are only produced in the roots and diffuse to the stem.
Q10:
A plant seedling was put in a cupboard and a single light bulb was hung above it for 2 days. Which of the following would be true about the concentration of auxins on sides of the coleoptile tip?
- AThe concentration of auxins on the right side would be higher.
- BThe concentration of auxins on the illuminated side would be higher.
- CThe concentration of auxins on the left side would be higher.
- DThe concentration of auxins on all sides would be equal.