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.
Safranin-stained cross-sections of etiolated hypocotyls in three height classes showing the extent of xylem differentiation. Height classes shown are: A, 2 to 3 cm; B, 4 to 6 cm; and C, 7 to 8 cm. Representative micrographs of the maximum size of vascular bundles at the base of the hypocotyl are shown in each case. The micrographs are black and white digital reprints of the scanned original color slides. Bar = 30 μm.
