NEET BIOLOGY

Detailed explanation-1: -They are dead cells as they do contain any protoplasm. They are elongated tube-like structures having a lignified wall. The transport of water and minerals through the xylem occurs by the transpiration pull, i.e. the negative pressure which is generated due to the evaporation of water through leaves.

Detailed explanation-2: -Xylem consists of dead cells. The cells that make up the xylem are adapted to their function: They lose their end walls so the xylem forms a continuous, hollow tube. They become strengthened by a substance called lignin .

Detailed explanation-3: -Xylem is a complex permanent tissue specialized for transport of water and minerals. The cells of xylem are dead at maturity and devoid of protoplasm except for xylem parenchyma cells, which are living cells.

Detailed explanation-4: -The xylem consists of tracheary elements, xylem parenchyma cells, and xylem fiber cells. Tracheary elements are dead, hollow cells with patterned cell walls comprising xylem vessels and tracheids, which function as conductive hollow tubes for water and nutrient transport throughout the plant body.

Detailed explanation-5: -Phloem parenchyma and companion cells are elements of phloem and both are living cells. Phloem fibres also called as bast fibres are the only dead cells present in the phloem.