What are the common chemical features of gibberellins, and to which general class of compounds are they related? Are all gibberellins biologically active?
Briefly describe seven different physiological responses to GA.
What are some commercial applications of GA in agriculture?
Which pathway produces the early intermediates for GA biosynthesis? What three cellular compartments are involved in gibberellin biosynthesis, and what are the major biochemical steps in each compartment?
Which reactions cause gibberellin inactivation? In what cellular compartment do they occur?
GA can inhibit its own synthesis by negative feedback regulation. Which steps in the GA biosynthesis pathway are down-regulated by GA?
One of the traits Mendel used to discover the laws of genetics in peas was dwarfism. How have subsequent genetic studies in dwarf peas helped to identify the biologically active GA?
How can plant height be altered through genetic engineering?
What are the three main classes of gibberellin response mutants, and how do they differ from mutants blocked in GA biosynthesis?
What effect does GA-binding have on the GID1 receptor?
What is the role of DELLA proteins in the GA response? How does GA-binding to its receptor affect DELLA proteins? Describe the series of steps following GA-binding that leads to the GA response.
The GA and phytochrome pathways are integrated. Compare and contrast the GA signaling pathways in dark-grown (tall) and light-grown (short) Arabidopsis hypocotyls.
How do cereal aleurone layers respond to GA, and what role does this response play in germination?
What is the role of the GAMYB protein in the response of barley aleurone layers to GA?
How do mutations in GAMYB affect flower development in rice?
What are the lag times for gibberellin-induced growth in deep-water rice and peas, and how do these lag times compare with that for auxin-induced growth in coleoptiles? Are the mechanisms of growth the same for the two hormones? How do they differ?