Presentation on theme: "Chapter 25 Plant Responses and Adaptations.. Set Up Foldable Fold Long and Skinny (hotdog) Fold short and fat 2 times (hamburger) Open so looks like below,"— Presentation transcript:
Chapter 25 Plant Responses and Adaptations.
Set Up Foldable Fold Long and Skinny (hotdog) Fold short and fat 2 times (hamburger) Open so looks like below, crease is on top
What is a tropism? Tropism ~ a response of a plant to an environmental stimulus.
Tropism Tropism is growth in response to an external stimulus (factor that elicits a response). Positive tropism: Plant growth toward a stimulus (water, sunlight) Negative tropism: Plant growth away from a stimulus (spilled gas, toxins, too much sun or not enough)
What is phototropism? Phototropism ~ a tendency of plants to grow toward a source of light.
Phototropism Phototropism is a change in the growth of a plant in response to light. The stalk displays positive phototropism growing towards the light.
What is gravitropism? Gravitropism ~ a tendency of a plant to grow in a direction in response to the force of gravity.
What is thigmotropism? Thigmotropism ~ the response of plants to touch.
Geotropism (Gravitropism) Geotropism is a change in the growth of a plant in response to gravity. The stalk displays a negative geotropism growing away from gravity. The roots display a positive geotropism growing towards gravity.
Hydrotropism Hydrotropism is a change in the growth of a plant in response to water. The roots display a positive hydrotropism growing towards water.
Turgor Pressure Click on link above for example
The cell’s vacuole does not have any water in it. The cell is flaccid. The vacuole does not have a lot of water in it. The vacuole and cell wall push against each other. The vacuole is now full of water.