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Plant hormones
There are five general classes of hormones: auxins, cytokinins, gibberellins, ethylene, and abscisic acid. for more details see plant biology
Types of Movement
Plants in motion: http://plantsinmotion.bio.indiana.edu/plantmotion/starthere.html
- A great collection of short time lapses showing plants in motion
Phototropism
- movement in response to light.
- shoots grow toward light and are positively phototropic; roots grow away from light and are negatively phototropic.
- IAA increase in shaded side → plant curve toward light
- wavelengths less than 500μm—is most effective in producing a growth response.
Gravitropism
- response to gravity
Thigmotropism
- reaction to a solid object
- eg. tendrils of climbing plants wrapping around a support
- IAA (lengthening) and ethylene (contracting) are probably involved
Other
via Tropism
- Chemotropism, movement or growth in response to chemicals
- Gravitropism (or geotropism), movement or growth in response to gravity
- Hydrotropism, movement or growth in response to moisture or water
- Heliotropism, movement or growth in response to sunlight
- Phototropism, movement or growth in response to lights or colors of light
- Thermotropism, movement or growth in response to temperature
- Thigmotropism, movement or growth in response to touch or contact
Reading / / Notes
- “The Power of Movement in Plants” Charles Darwin's book on phototropism > http://www.gutenberg.org/etext/5605
- Roger P. Hangarter's research into plant's responses to environmental stimuli: http://www.bio.indiana.edu/%7Ehangarterlab/abstracts/research.html
- Roger P. Hangarter & Dennis DeHart - Slow Life: http://plantsinmotion.bio.indiana.edu/usbg/ http://dennis4.fatcow.com/lowlife/slowlife_intro.html