biological_process Term "pollen development" (GO:0009555)

Term Name	pollen development
Term Accession	GO:0009555
Aspect	biological_process
Synonyms (7)	formation of generative and vegetative cells, GO:0009564, GO:0048231, male gametophyte development, male gametophyte formation, microgametophyte development, pollen grain formation
Definition	The process whose specific outcome is the progression of the pollen grain over time, from its formation to the mature structure. The process begins with the meiosis of the microsporocyte to form four haploid microspores. The nucleus of each microspore then divides by mitosis to form a two-celled organism, the pollen grain, that contains a tube cell as well as a smaller generative cell. The pollen grain is surrounded by an elaborate cell wall. In some species, the generative cell immediately divides again to give a pair of sperm cells. In most flowering plants, however this division takes place later, in the tube that develops when a pollen grain germinates.
Comment	None
Source Ontology Database	The GO browser of Gene Ontology Database