The structure of these organs may be written out as a formula containing degree symbols, superscript 'r's and 'o's, and square and curly brackets. In many families, two parts of this structure are combined into a single organ called the "column." The development of these structures depends on the additive effect of three kinds of genes according to the ABC model. An organism's ability to develop these structures is known as (*) vernalization. The outermost part of this structure, comprising the corolla and the calyx, is known as the perianth. A classic example of coevolution is the development of these organs and the 
The structure of these organs may be written out as a formula containing degree symbols, superscript 'r's and 'o's, and square and curly brackets. In many families, two parts of this structure are combined into a single organ called the "column." The development of these structures depends on the additive effect of three kinds of genes according to the ABC model. An organism's ability to develop these structures is known as (*) vernalization. The outermost part of this structure, comprising the corolla and the calyx, is known as the perianth. A classic example of coevolution is the development of these organs and the evolution of bumblebees, which interact with their stamens. For 10 points, name these reproductive organs of angiosperms, where pollen is produced.