Test Your Knowledge on Plant Hormones

Effects of Plant Hormones:

• Survival of plants depends on their ability to respond to changes in their environment
• Plants respond to several types of stimuli including light, gravity, physical objects, herbivory, water, and physical touch
• Plants do not possess a nervous system; their responses rely on chemical substances that are released or altered in response to a stimulus
• Phytochromes are plant pigments that react to different types of light, leading to different plant responses
• Phytochrome pigments exist in two forms: PR (inactive) and PFR (active)
• Absorption of different wavelengths of light causes a reversible conversion between the PR and PFR forms of phytochrome
• Phytochrome is responsible for seed germination: red light triggers germination while far-red light prevents it
• Phytochrome controls flowering: long day plants flower when the nights are short, high levels of PFR activate flowering, and PFR activates expression of genes that stimulate flowering
• Phytochromes are also involved in plant responses to light and gravity by acting as transcription factors
• PFR can move into the nucleus via the nuclear pores and bind to a protein known as phytochrome-interacting factor 3 (PIF3)
• PIF3 can initiate transcription and activate various different genes, controlling many different aspects of plant growth and development
• The length of night can be detected by a plant because it determines the quantities of different forms of phytochrome in the leaf

Do you know how plants respond to changes in their environment and stimuli? Test your knowledge with our quiz on the effects of plant hormones. Learn about the role of phytochromes in seed germination, flowering, and plant responses to light and gravity. Discover how different wavelengths of light can trigger reversible conversions in phytochrome pigments and how PFR can activate genes that control plant growth and development. Take the quiz and become an expert on plant hormones!