OBJECTIVE FORESTRY

Detailed explanation-1: -Tracheids, vessels, xylem fibers, and xylem parenchyma are the four types of elements that make up the xylem. Tracheids: Tracheids are long, tube-like cells with lignified walls and a tapering end. These are non-protoplasmic and dead.

Detailed explanation-2: -The xylems structure consists of lignified tracheary elements like tracheids and vessel elements which are dead at maturity. Both tracheary elements are long hollow cells with tapered end walls.

Detailed explanation-3: -The xylem tracheary elements consist of cells known as tracheids and vessel members, both of which are typically narrow, hollow, and elongated. Tracheids are less specialized than the vessel members and are the only type of water-conducting cells in most gymnosperms and seedless vascular plants.

Detailed explanation-4: -A vessel element or vessel member (also called trachea or xylem vessel) is one of the cell types found in xylem, the water conducting tissue of plants. Vessel elements are typically found in angiosperms (flowering plants) but absent from most gymnosperms such as conifers.