Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
(A). Germinated pollen on the stigma. (B). Pollen tubes in the middle of the style. (C). Pollen tubes at the base of the style. (D). Pollen tubes penetrating into an ovule. Vertical bars represent the standard deviation.
