Download to read offline
Plant tissues
- 1. Plant Tissues By Dr. AnuragTitov Professor Govt. Madhav Science PG College, Ujjain
- 2.
- 10. Meristematic Tissue • Cellscapable of division • No intercellular spaces • Active metabolism no food storage • Cells may be round, oval, rectangular or polyhedral • Dense protoplasm • Thin cell wall of cellulose • Conspicuous nucleus • Vacuoles absent or very small
- 11. Classification based onPosition • Apical Meristem 1. Dermatogen 2. Periblem 3. Plerome • Lateral meristem • Intercalalary Meristem
- 13. Classification based onstage of development • Promeristem or primordial meristem Group of young meristematic cells in early embryonic stage at the shoot and root tip of a plant from which the other meristems are derived. It forms the primary meristem in plants. Apical meristems are derived from promeristem and are present below the promeristem at shoot tip and root tip. They continuously divide and form permanent tissues in plants Also called as Urmeristem or Embryonic meristem
- 14. • Primary Meristem •Secondary meristem Classification based on Origin
- 15. • According toHaberlandt 1. Protoderm 2. Procambium 3. Ground Meristem Classification based on Function
- 16. Permanent Tissues 1. Simple: a.Parenchyma : Living thin walled, isodiametric cells, with or without intercellular spaces. Help in food storage, exchange of gases and photosynthesis
- 18. b. Collenchyma :Living cells with thickened walls due to cellulose or/ and lignin. 3 types angular, lacunar and Lamellar Provide strength, make hypodermis, storage and photosynthesis.
- 19. c. Sclerenchyma: Deadcells, lignified thick walls. Provide mechanical strength. Sclerieds or stone cells: Cells of same shape present in pith, cortex, pericycle & fruit pulp Fibres: Long with lignified wall, narrow lumen, tapering ends. Provide strength. Present in phloem, xylem and pericycle
- 21. 2. Complex; 1. Xylem:Tracheids, Vessels, parenchyma & Fibres 2. Phloem: Sieve tubes, companion cells, parenchyma & Fibres
- 27. 3. Special tissues:Glands secrete Oil, gum, resin etc. a. Glandular b. Laticiferous
- 61. Organization of ShootApical Meristem • Regions of Shoot Apex : Wardlaw (1957) described 5 regions
- 62. Foster (1939) identifiedfor regions in Ginkgo biloba Popham & Chan (1950) and Singh & Singh (1970) reported cambium as additional region
- 63. • Apical cellTheory: Hofmeister (1857) proposed, Nageli (1878) explained
- 64. • Histogen Theory:Hanstein (1870)
- 65. • Tunica CorpusTheory : Schmidt (1924)
- 66. • Histogenic LayerConcept: Derman (1947) L1 – Epidermis L2 – Cortex L3 – Stele
- 67. • Mantle- CoreConcept: Popham and Chan (1950)
- 68. • Annaeu initial& meristeme d, attentae theory: Buvat (1955)