AP BIOLOGY

Detailed explanation-1: -Xylem vessel is a long tube made up of dead cells joined end to end. It is a non-living tube which runs from roots of the plants and runs through the stem and reaches every leaf.

Detailed explanation-2: -Sieve tubes, which are columns of sieve tube cells having perforated sievelike areas in their lateral or end walls, provide the main channels in which food substances travel throughout a vascular plant.

Detailed explanation-3: -Xylem cells form long tubes (xylem vessels) that allow water and mineral ions to travel easily through them in one direction, from the soil around the plant up the stem and to the leaves. These tubes are hollow: mature xylem cells are dead. Spirals of woody lignin strengthen the xylem vessels.

Detailed explanation-4: -The vascular system is comprised of two main types of tissue: the xylem and the phloem. The xylem distributes water and dissolved minerals upward through the plant, from the roots to the leaves. The phloem carries food downward from the leaves to the roots.

Detailed explanation-5: -Plants have two transport systems-xylem and phloem . Xylem transports water and minerals. Phloem transports sugars and amino acids dissolved in water.