Fig. 1.
Micrograph of vascular bundle in a grass stem showing large open vessels (metaxylem), early formed collapsed vessels (protoxylem) and phloem.
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.