Bachelor’s Degree Programme (BSCG) – Plant Anatomy and Embryology Assig. Answer | BBYCT – 135 (Q- 3)
3. a) Enlist the major characteristic features of halophytes.
b) List various types of simple and complex tissues. Describe complex tissues with suitable diagrams.
a) These are a special type of plants, which grow in saline soil with a high concentration of sodium chloride, magnesium sulphate and magnesium chloride and/or other salts. Halophytes are found near saline lakes (Sambhar lake) and on the coasts of oceans.
General characters of Halophytes:
• Halophytes of subtropical places are herbs, and those found in tropical zone are shrubs and trees.
• The roots are present closer to the surface.
• Adventitious roots that develop from the main stem of halophytic plants support these plants, after entering into the soil.
• A special type of roots is developed in halophytes, which are called pneumatophores. These roots arise vertically from the ground and contain numerous pores called Lenticels for the exchange of O2 and CO2.
• Stems are fleshy and covered with hairs.
• The leaves of halophytes are less developed and fleshy.
• Most of the halophytes show vivipary. The seeds germinate inside the fruit, which is still attached to the parent tree. The germinated seeds fall on the soil and begin their development.
Examples: Rhizophora and Sonnertia.
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i) Nature of the Tissue – Homogenous
ii) Example – Parenchyma, Collenchyma, Sclerenchyma
iii) Function – Repair of tissue, food storage, secretion, and structural support
iv) Distribution – Located in every part of the plant
v) Cell Composition – Composed of a single type of cell/ all cells perform a similar function
i) Nature of the Tissue – Heterogenous
ii) Example – Xylem, phloem
iii) Function – Conduction of minerals and water to various parts of the plant body
iv) Distribution – Primarily located in the vascular regions
v) Cell Composition – Composed of various types of cells that perform various functions