The cells are no longer alive. Lignin gives strength and support to the plant. We call lignified cells wood. Phloem The phloem moves food substances that the plant has produced by photosynthesis to where they are needed for processes such as: growing parts of the plant for immediate use storage organs such as bulbs and tubers developing seeds Transport in the phloem is therefore both up and down the stem.
The cells that make up the phloem are adapted to their function: Sieve tubes — specialised for transport and have no nuclei. Each sieve tube has a perforated end so its cytoplasm connects one cell to the next. Definition noun, plural: xylem fibers Any of the fiber s made up of dead sclerenchyma cells in between the xylem vessels and tracheids of the xylem tissue, and chiefly provide mechanical support Supplement The xylem is the vascular tissue responsible for the upward conduction of water and nutrient s from the root s.
The xylem tissue moves water and nutrient s to various parts of the plant such as shoots and leaves. Its major components include xylem parenchyma , xylem fiber s, tracheid s, and xylem vessels. The xylem fibers are non-living sclerenchyma cells as they lose their protoplast at maturity.
These cells are found in between the tracheid s and xylem vessels of the xylem tissue. Sclerenchyma cells are narrow and elongated cells with tapering ends. Phloem consists of living cells. The cells that make up the phloem are adapted to their function:. Plant transport tissues - Xylem and phloem Xylem The xylem is a tissue which transports water and minerals from the roots up the plant stem and into the leaves. 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. Lignin gives strength and support to the plant. We call lignified cells wood. Phloem The phloem moves food substances that the plant has produced by photosynthesis to where they are needed for processes such as: growing parts of the plant for immediate use storage organs such as bulbs and tubers developing seeds Transport in the phloem is therefore both up and down the stem.
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