Photoperiodism is the ability of a plant to flower in response to the length of day or night. They can be either short-day, long-day, or day-neutral plants.

Animation - Phytochrome Signaling
Animation - Phytochrome Signaling McGraw-Hill Companies Animation with audio.
long-day plant
long-day plant A Dictionary of Ecology | 2004 MICHAEL ALLABY, Copyright Encyclopedia.com Visit the web site for the definition.
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Photoperiodism
Photoperiodism Biology Reference The term "photoperiodism" was coined to describe a plant's ability to flower in response to changes in the photoperiod: the relative lengths of day and night.
Photoperiodism - YouTube
Photoperiodism - YouTube Posted by forensicked September 23, 2008 "A short video (10:24 minutes) about how plants respond to the seasons."
Photoreception: what are Phytochromes?
Photoreception: what are Phytochromes? Plant-Biology.com Plant photoreceptors are able to respond to visible light. There are three main classes of photoreceptors.... Visit the web site for t
Phytochrome
Phytochrome Wikipedia.org Phytochrome is a photoreceptor, a pigment that plants use to detect light. It is sensitive to light in the red and far-red region of the visible spectrum. Visit the we
Plant Biology: Photoperiod response, photoperiodism
Plant Biology: Photoperiod response, photoperiodism "Photoperiod describes the duration of daylight in the daily cycle, and the term photoperiodism describes an organism's ability to detect changes
Spark Notes: Plants: Essential Processes-Photoperiodism
Spark Notes: Plants: Essential Processes-Photoperiodism Plants have a wide variety of flowering strategies involving what time of year they will flower and, consequently, reproduce. In many plant
The Open Door Web Site: IB Biology: Plant Physiology - Photoperiodism
The Open Door Web Site: IB Biology: Plant Physiology - Photoperiodism by Paul Billiet Two Powerpoint presentation, text, an d illustrations on photoperiodism which is the ability of a plant or a
What Is a Phytochrome?
What Is a Phytochrome? Written by Caitlin Kenney WiseGeek.com Phytochrome is a pigment found in most plants and some bacteria that is used to monitor the color of light. Visit the web site