The phloem elements which are formed from the procambium of apical meristem are called primary phloem.
Reason: Phloem fibresare generally found in primary pholem. These are generally absent in the primary phloem but are found in the secondary phloem. Like xylem, phloem is also a complex tissue. They support the conductive cells of the phloem and provide strength to the stem. Question No : 19 An organised and differentiated cellular structure having cytoplasm but no nucleus is called _________. Parenchyma may store various types of materials like, water, air, ergastic substances. Phloem Fibre: These are also called bast fibres and are made up of sclerenchyma. Parenchyma tissue normally has prominent intercellular spaces. In monocots, usually phloem parenchyma is absent. Some of the fibres used in textile industries like Jute, Hemp are obtained from the bast fibres of secondary phloem. It is usually colourless. Parenchyma tissue normally has prominent intercellular spaces. Parenchyma. The ependyma is composed of ependymal cells known as ependymocytes, which is a type of glial cell. Phloem parenchyma is usually absent in monocotyledonous. Natural Bast fibres are strong and cellulosic. Parenchyma is a living tissue and made up of thin walled cells. Posted at 06:54h in Uncategorized by 0 Comments. It is comprized of conducting elements, parenchyma and sclerenchyma cells, the bast or phloem fibres. It contains a lining layer of cytoplasm. The conduction of food material takes place through cytoplasmic strands. LNFs, eg, bast fibres, are made up of similar elements as wood fibres, namely, cellulose, hemicellulose, lignin and other minor elements (Table 6.1). The cells are dead. Phloem, also called bast, tissues in plants that conduct foods made in the leaves to all other parts of the plant. Bast fibres are obtained from 1) Phloem 2) Pith 3) Seed surface 4) Epidermis 11. Companion cells are absent in pteridophytes and gymnosperms. They are distinguished into sieve cells and sieve tubes. ... At maturity, these fibres lose their protoplasm and become dead. Phloem fibres (bast fibres) are made up of sclerenchymatous cells. Phloem parenchyma also contain resins and tannins in some plants. 1A). Phloem is the living bark. The fibres support the conductive cells of the phloem and provide strength to the stem. Sucrose accumulation within sugarcane stem inter-nodes has been suggested to utilize a symplasmic phloem unloading pathway followed by post-phloem su-crose … In contrast to sieve elements, the companion cells have cytoplasm and a prominent nucleus. On the other hand, the spongy chlorenchyma has cells with huge gaps in distances in order to facilitate aeration. The ground tissue of plants includes all tissues that are neither dermal nor vascular. The phloem fibres are much elongated, unbranched and have pointed, needle-like apices. Question No : 16 Phellogen and phellem respectively denote. These are generally absent in the primary phloem but are found in the secondary phloem. 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