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A dumb-bell shaped guard cells
Sugarcane are monocots and like all monocots, they have dumb-bell shaped guard cells. In the case of dicots, the guard cells are bean-shaped. Guard cells are a part of the stomatal apparatus on the epidermis that enclose the stomatal pore. They regulate the opening and closing of stomata.
The arrangement of veins and veinlets in the leaf lamina is known as venation. In dicots, the veinlets form a network which is known as reticulate venation. In monocots, the veins run parallel to each other and the arrangement is known as parallel venation.
In dicots, the radicle elongates directly into the soil and forms tap-roots. Whereas in monocots, the primary root is short-lived and is replaced by a large number of roots originating from the base of the stem. This is known as the fibrous root system.
The open vascular bundle is a feature of dicot plants as they have cambium in between xylem and phloem. Monocots like sugarcane have no cambium between the xylem and the phloem and, hence, have a closed vascular bundle.