Vascular tissue are typically found on the undersides of the leaves rather than on the top, since the phloem transports sugars manufactured by the plant and they are closer to the lower surface. Vascular tissue Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem. These two tissues transport fluid and nutrients internally. There are also two meristems associated with vascular tissue: the vascular cambium and the cork cambium. All the vascular tissues within a particular plant together constitute the vascular tissue system
Aphididae wing beats in synchrony. All aphids have very small eyes, sucking mouthparts in the form of a relatively long, segmented rostrum, and fairly long antennae. These insects are so small (a few millimeters in length), that winds can transport them for fairly long distances. They are often green, but might be red or brown, as well. They move quite slowly and cannot jump or hop. Aphids excrete a sugary liquid called honeydew, because the plant sap from which they feed contains excess carbohydrates relative to its low protein content. To satisfy their protein needs, they absorb large amounts of sap