Asarum canadense Xylem
This is a transverse section on the stem of Asarum canadense, or wild ginger under crossed polarizers showing a vascular bundle. The xylem is birefringent on account of its ordered cellulose structure. The Xylem walls are helical like a spring, and this can bee seen where the ends are visible in several areas.
The protocol was as follows. Specimens fixed in FAA (formaldehyde, acetic acid, ethanol) 48 hr. Dehydrated in 35, 50, 75, 85, 95, 99 % IPA in water, 6 hours each min. Infiltrated in xylene saturated with Paraplast for 2 days, followed by 2 changes of melted Praplast for 2 hours each. Embedded in Paraplast. Sectioned on a Spencer 820 microtome at 11 micron. Cleared in xylene, 5 min, 2X. Rehydrated in 99, 95, 80, 70 %IPA. Stained in Johansen's Safranin-O, Fast Green (24 hours in Safranin-O, 15 sec. in fast green). Cleared 2 X in xylene 10 min each and mounted with DPEX.
Photographed on a Spencer 42 petrographic polarizing microscope under crossed polarizers using an original magnification of 200X, using a Sony NEX 5N with a Leica MIKAS 1/3X adapter.
Asarum canadense Xylem
This is a transverse section on the stem of Asarum canadense, or wild ginger under crossed polarizers showing a vascular bundle. The xylem is birefringent on account of its ordered cellulose structure. The Xylem walls are helical like a spring, and this can bee seen where the ends are visible in several areas.
The protocol was as follows. Specimens fixed in FAA (formaldehyde, acetic acid, ethanol) 48 hr. Dehydrated in 35, 50, 75, 85, 95, 99 % IPA in water, 6 hours each min. Infiltrated in xylene saturated with Paraplast for 2 days, followed by 2 changes of melted Praplast for 2 hours each. Embedded in Paraplast. Sectioned on a Spencer 820 microtome at 11 micron. Cleared in xylene, 5 min, 2X. Rehydrated in 99, 95, 80, 70 %IPA. Stained in Johansen's Safranin-O, Fast Green (24 hours in Safranin-O, 15 sec. in fast green). Cleared 2 X in xylene 10 min each and mounted with DPEX.
Photographed on a Spencer 42 petrographic polarizing microscope under crossed polarizers using an original magnification of 200X, using a Sony NEX 5N with a Leica MIKAS 1/3X adapter.