15: Development
Development is the process by which an organism changes over its life. In angiosperms, development after sperm from the pollen tube fertilizes the egg in the ovule, forming the diploid zygote . Through cell division and differentiation, the zygote forms a mature embryo, which lies dormant within the seed until germination (Figure \(\PageIndex{1}\)). A seedling emerges and continues to develop into mature plant, which will ultimately flower and undergo pollination, completing the life cycle.
The variety of tissues and organs in the plant body result from differences in gene expression. While all the diploid cells in a plant have the same genetic information, which genes are active in each structure varies, resulting in a complex, multicellular organism.
Attribution
Melissa Ha ( CC-BY-NC )
Thumbnail image: Different stages of germination in Arabidopsis . Image by Alena Kravchenko ( CC-BY-SA )