Lesson 13 Which way is up?
Completion requirements
Introduction
How do plants know which end to grow leaves on and which end to grow roots on?
A13.1 Plants need to respond to the sun and the soil.
Plants do not have eyes, so they cannot see where the sun is or where the soil is, yet it is extremely important they grow leaves in the sunlight and roots in the soil. How does a plant do this?
Plants, just like other organisms, respond to stimuli in their environment. This means they take cues from the area around them that help them know where to grow their leaves and roots. In this lesson, we will study these cues and the systems the plants use to interpret them. We will also look at how scientists discovered these systems.
Plants, just like other organisms, respond to stimuli in their environment. This means they take cues from the area around them that help them know where to grow their leaves and roots. In this lesson, we will study these cues and the systems the plants use to interpret them. We will also look at how scientists discovered these systems.
Targets
By the end of this lesson, you will be able to- explain the processes of phototropism and gravitropism
- trace the development of theories of phototropism and gravitropism
Watch This
Plant Hormones: Tropisms © YouTube FuseSchool-Global Education
This video will introduce the concepts of phototropism and gravitropism to you. Please note this video uses an older term for gravitropism and calls it geotropism instead.
The video will also introduce positive and negative tropisms as well.