Study questions for Hormone Chapter 14

1. Know what these terms mean.. again, as before, do not just memorize the definition.. understand the concept, the related process, the anatomy and so on.

• Abscisic acid (ABA)
• all or none response
• apical dominance
• auxin
• circadian rhythms
• critical night length
• cytokinins
• day- neutral plants
• differential growth
• dosage-dependent response
• endogenous rhythms ( including your own)
• ethylene
• gibberellins
• gravi-, chemo-, photo-, thigmo ( not only plants respond this way) ...responses - for each give an example of how it would modify plant structure ( ie. root growth and what hormone would be involved if any)
• nastic response
• hormone
• indolacetic acid
• long day vs short day vs neutral plants
• morphogenic response
• perception of a stimulus, presentation time, threshold for a stimulus, transduction, response to a stimulus
• photoperiod
• phytochrome
• taxis
• tropic response
• vernalization

2. Name 5 environmental factors that plants re able to detect as stimuli. In each case what types of information are provided to the plant? what are they actually responding to.

3. In the perception of a s stimulus, what are presentation time and threshold? how sensitive should a plant be? how can a mimosa who shuts it leaves with heat distinguish between your hot breath and a fire?

4. Give the 5 generally recognized classes of hormones, give several kinds of reactions, and give the characteristics of each of these hormones. What classes are now beginning to be recognized? what are their characteristics and responses?

5. What are the 4 ways a plant can respond to s stimulus? define and give examples of each. Why are some responses classified as positive, negative or dia whereas others are not\.?

6. What are short day vs long day plants. day neutral? What is critical day length? For what reasons did these timing responses evolve? consider the consequences of growing spinach in the spring Vs summer.

7. What is the difference between endogenous and exogenous rhythms? Give several examples of each type. Include some that have either short or long periods.