Question

Explain Detailed structure of phloem

Answer 1

Dear student. Phloem sieve tubes are primarily composed of two main types of cells – sieve element cells and companion cells The phloem also contains schlerenchymal and parenchymal cells which fill additional spaces and provide support. Sieve elements typically lack a nucleus and contain none to a very small number of ribosomes. The two types of sieve elements, sieve tube members and sieve cells, have different structure. The companion cells are intimately associated with the sieve tubes both structurally and functionally. The sieve tube and the companion cells are derived from a common mother cell of the procambial strand in primary phloem or from a phloem mother cell derived from the cambium in secondary phloem. Regard