Why does Phloem consist of living cells whilst Xylem consists of dead cells?
Answers
Explanation:
Xylem parenchyma cells will make tyloses“stoppers” for tracheary elements made by parenchyma cells (“stoppers”) which will grow into dead tracheary elements and stop water if needed.
Phloem is the chief conducting tissue of vascular plants responsible for translocation of organic solutes. The phloem is composed of several different kinds of cells. The basic components are sieve elements, companion cells, phloem parenchyma and phloem fibres. Sieve element is the main component of phloem and these elements are placed one over the other to form a continuous sieve tube. The sieve elements are living elements without nucleus because each sieve cell is present in association with companion cells which contain active protoplasts and cellular organelles. Phloem parenchyma is living parenchymatous cells present as components of phloem. They store food materials in the form of starch and fats. Phloem fibres are the only non-living cells present in association with phloem. They provide mechanical support and give strength and rigidity to the organ.