Plant Responses

TROPISM Plant movement in response to an environmental stimulus -Caused by hormones

TROPISM POSITIVE NEGATIVE If the plant moves TOWARD the stimulus If the plant moves AWAY from the stimulus

Phototropism Movement of plants toward light

Gravitropism (Geotropism) Movement of plants in response to gravity Positive is toward gravity (roots grow down) Negative is away from gravity (shoot, stems, and leaves grow up) Allows plants to grow properly and get nutrients and sunlight

Thigmotropism Plants moving in response to touch. Positive is toward touch (vines wrap around structures) Negative is away from touch (some plants close up when touched)

TROPISM QUIZ Identify the type of tropism in the following pictures

Gravitropism

Phototropism

Gravitropism

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Watch the Tropisms Prezi to see video examples https://prezi.com/d6hkc6slagxl/plants-tropisms/