Pollen tube through wind, water or pollinators. The last step before fertilization is the growth of the pollen tube to transfer non-motile sperm to the protected egg. Pollen tubes are unique to plants and their structure had evolved over plant history. The pollen tube formation is complex and the mechanism is not fully understood, but is of great interest to scientists. Pollen is produced by the stamen, the male reproductive organ of the flower. Each pollen grain contains a vegetative cell, and a generative cell that divides to form two sperm cells. The pollen is delivered by the opening of anthers for
What Is This Thing Called Love? What Is This Thing Called Love? "What Is This Thing Called Love?" is a 1929 popular song written by Cole Porter, for the musical "Wake Up and Dream". It was first performed by Elsie Carlisle in March 1929. The song has become a popular jazz standard and one of Porter's most often played compositions. "Wake Up and Dream" ran for 263 shows in London. The show was also noticed in New York, and the critics praised Tilly Losch's performance of the song. The show was produced on Broadway in December 1929; in the American rendition, "What Is This Thing Called