Tissue (biology) parts of the plant. The complex tissue consists of more than one type of cells which work together as a unit. Complex tissues help in the transportation of organic material, water, and minerals up and down the plants. That is why it is also known as conducting and vascular tissue. The common types of complex permanent tissue are: Xylem and phloem together form vascular bundles. Xylem consists of: Xylem serves as a chief conducting tissue of vascular plants. It is responsible for the conduction of water and mineral ions/salt. Xylem tissue is organized in a tube-like fashion along the main
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