Root cap parenchyma in Zea mays embryo
1/ Micrograph of a longitudinal section.
This is a paraffin section (10 μm) through a Zea mays embryo fixed with FAA. It was stained with PAS to visualize polysaccharides. The root cap at the extremity is protected by a protective tissue called « coleorhiza« . The root cap and the coleorhiza are both constituted of parenchyma cells with a thin cellulosic wall.
2/ Micrographs of a cross section through the root cap.
Epon cross section (1μm) made with a diamond knife Histo and stained with methylene-blue basic fuchsin. Starch grains appear as pink stained globules (detail in the middle). On the right, electron micrograph showing four amyloplasts (A) containing each several starch grains (ga) in a root cap cell. They appear as electron dense.