Pollen of Pulmonaria, SEM

Pollen of Pulmonaria. Coloured scanning electron micrograph (SEM). Pulmonaria (lungwort) can be herbaceous or semi-evergreen rhizomatous perennials with terminal clusters of funnel-shaped flowers in late winter or early spring, and often strikingly patterned leaves developing in summer. Pollen grains are the male sex cells of a flowering plant. Their characteristic surface is used by botanists to recognise and classify plants. Pollen in plants is used for transferring male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anther of a flower to the stigma of the same flower. Magnification: x200 when printed at 10 centimetres wide., by STEVE GSCHMEISSNER/SCIENCE PHOTO LIBRARY