Plants Move

TROPISMis a biological phenomenon, indicating growth or turning movement a plant in response to an environmental stimulus

TROPISMPOSITIVE

If the plant moves TOWARD the stimulus

NEGATIVE If the plant moves

AWAY from the stimulus

Phototropism

Movement of plants toward light

Why?Maximize amount of sun for photosynthesis to make their food.

Phototropismhttp://www.youtube.com/watch?NR=1&v=KQOC_bPrqFs&safety_mode=true&persist_safety_mode=1

Gravitropism

http://www.youtube.com/watch?v=mYZXax8V_L0&feature=related&safety_mode=true&persist_safety_mode=1

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)

Why?Allows plants to grow properly and get nutrients and sunlight

Hydrotropism

http://virtualastronaut.tietronix.com/textonly/act25/text-plants.html

Movement by plants toward water.

Why?Roots search for and grow toward water, because it is needed for photosynthesis and to support cell structure.

Thigmotropism

http://www.youtube.com/watch?v=8HeedWWe6VA&feature=related&safety_mode=true&persist_safety_mode=1

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)

Why?to support leaves as they grow higher to reach the sun to make more food (photosynthesis).

Gravitropism Gravity causes a response in plant growth

In the picture above, which part of the plant exhibits positive tropism, and which exhibits negative tropism?

Hydrotropism The way a plant grows or bends in response

to water

Why would it be important for some parts of a plant to be pulled toward water?

Thigmotropism Plants bend and grow because of touch.

What are some other ways a plant can be “touched”?

Phototropism The way a plant grows or bends in response

to light.

Why do you think sunflowers were given their nickname?

Hydroptropism

Gravitropism

Phototropism

Gravitropism

Phototropism

Thigmotropism

TROPISM QUIZ

Identify the type of tropism in the following pictures

1

2

3

4

5

6

7

http://www.youtube.com/watch?v=Ze8NV7cvW8k&feature=results_main&playnext=1&list=PL5464C68C7644DD4D&safety_mode=true&persist_safety_mode=1

8

9

10

http://www.youtube.com/watch?v=8SkKuwbmR5Y&feature=related&safety_mode=true&persist_safety_mode=1

11

http://www.youtube.com/watch?v=9sggQQuBU40&feature=related&safety_mode=true&persist_safety_mode=1

12

13

http://www.youtube.com/watch?v=mYZXax8V_L0&safety_mode=true&persist_safety_mode=1

14

15

http://www.youtube.com/watch?v=8HeedWWe6VA&feature=fvsr&safety_mode=true&persist_safety_mode=1

16

http://www.youtube.com/watch?v=FC5eBkDJbMs&feature=BFa&list=PL5464C68C7644DD4D&lf=results_main&safety_mode=true&persist_safety_mode=1

17

18

http://www.youtube.com/watch?v=Zq3UuHlPLQU&feature=related&safety_mode=true&persist_safety_mode=1

19

20

http://www.youtube.com/watch?v=frmyzIhD29Q&safety_mode=true&persist_safety_mode=1