HORTICULTURE

Detailed explanation-1: -The phloem consists of sieve elements, companion cells, phloem parenchyma cells and phloem fibers. Other cell types may be found in the phloem of certain plant species.

Detailed explanation-2: -The phloem is a complex tissue and is formed typically by three cell types, the sieve elements, the parenchyma cells, and the sclerenchyma cells (Figure 2a–d).

Detailed explanation-3: -The sieve tube is the conducting element of the phloem. It is formed from a vertical series of elongated cells, interconnected by perforations in their walls in areas known as sieve plates. The perforations may be restricted to smaller areas, sieve fields, several of which are contained in each sieve plate.

Detailed explanation-4: -Sieve tubes, found in angiosperms, are living cells that are associated with companion cells. The association with companion cells helps in distant transportation within the plant cells. The sieve tubes are made up of longitudinal arrangement of sieve tube members from end to end.