Q.Student while observing a slide of leaf section observed many stomata on the upper surface. He thought he has placed slide upside down. Teacher confirmed it is rightly placed. Explain.

The isobilateral leaf, typical of monocots, has both surfaces more or less equally illuminated (as in a vertically held or edge-on grass blade), and its internal structure is essentially symmetrical top to bottom. It resembles the dicot leaf in overall plan but differs in three ways: it is amphistomatic, carrying stomata on both the upper and lower epidermis rather than mainly the lower; its mesophyll is not split into palisade and spongy layers, remaining a single, roughly uniform mass of chlorenchyma; and its venation is parallel rather than reticulate, with the vascular bundles (conjoint, collateral, closed, each in a bundle sheath) running alongside one another rather than branching and anastomosing. A furt …