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
Pollen core pollen grains and stratigraphy of the core so researchers frequently select locations where the sediments are under anaerobic conditions. The cores are then subjected to pollen analysis by palynologists who are able to infer the proportions of major plant types from the concentrations of different pollen types found in the cores. There are a number of tools used for coring, often with specialized uses: Pollen core A pollen core is a core sample of a medium containing a stratigraphic sequence of pollen. Analysis of the type and frequency of the pollen in each layer is used to study changes in