Pollen is the plant’s equivalent of an animal’s sperms. It carries the male reproductive genes.
Pollen consists of tiny grains, each with a tough coat that is often patterned with characteristic ridges and spikes. When inhaled, the fine pollen causes allergies such as hay fever in some susceptible people. Pollen can be found in fossil deposits, making it possible to identify the plants that were living then – even though no actual plant fossils may be found.
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