LU4-LU6 Plant Biology: Growth, Development and Structure PDF
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Uploaded by PraisingHope3406
UNIMAS (Universiti Malaysia Sarawak)
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This PDF document appears to be a set of notes, possibly for high school biology, covering plant biology topics. The document includes information on growth, development, the structure of plants including tissues, and the rhizosphere. There are diagrams to aid the explanations making for a good study aid.
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LU4.1 Growth: Defined as the irreversible and permanent increase in size of the plant, its parts, or an individual cell. It includes parameters like cell size, tissue expansion, and...
LU4.1 Growth: Defined as the irreversible and permanent increase in size of the plant, its parts, or an individual cell. It includes parameters like cell size, tissue expansion, and overall plant mass. Development: Refers to a sequence of qualitative structural changes occurring throughout the plant's lifecycle, from germination to senescence (aging). Development involves: - Morphogenesis: The acquisition of form and structure. - Differentiation: Transformation of generalized cells into specialized ones. 1.DEFINITION OF GROWTH & 2. STAGES OF PLANT GROWTH 5. PRIMARY VS DEVELOPMENT - Primary Growth: SECONDARY GROWTH Occurs first and extends plant length above and Seed Germination: The initial stage where the seed absorbs below ground. water, breaks dormancy, and starts metabolic activities. Driven by apical meristems. LU4 Seedling Development: The seedling grows roots and shoots, - Secondary Growth: establishing itself in the soil. Occurs after primary growth, increasing Adult Plant Formation: The plant attains maturity with diameter and strength. fully developed tissues, organs, and reproductive structures. Controlled by lateral meristems. Includes growth from axillary/lateral buds, contributing to plant branching. 3.MERISTEMS (GROWING REGIONS) S 4. PHASES OF CELL GROWTH - Apical Meristem: - Located at the tips of roots and shoots. - Phase of Division (Meristematic Phase): - Responsible for primary growth, increasing the plant's length. - Involves mitotic cell division in the meristematic zone. - Lateral Meristem: - Produces new cells for growth. - Found along the sides of stems and roots. - Phase of Elongation: - Responsible for secondary growth, increasing the plant's girth - Cells increase in size, up to 10 times their original length. - Results in root penetration deeper into the soil. - Contributes to size and length of plant tissues. - Phase of Differentiation (Maturation): - Cells undergo specialization based on their position in the organ. - Differentiated cells form complex tissues like vascular bundles and perform specific functions. LU4.2 - Development Characteristics: Progression of chronological events like: - Growth Characteristics: Germination. Measured by increases in: seedling emergence Fresh or dry weight. Leaf appearance. Leaf area. Branching Plant height. Flowering. 12. FACTORS AFFECTING Fruiting. PLANT GROWTH Seedling 6.CHARACTERISTICS Maturation Senescence (aging). - Light: OF GROWTH AND Essential for photosynthesis, regulating stomata, and DEVELOPMENT floral induction. 7. PLANT GROWTH CURVE (SIGMOID CURVE) Intensity and quality affect plant processes. Duration influences leaf production and flowering. - Water: - Represents growth plotted against time: Constitutes 90% of the plant body. Necessary for: LU4 1. Lag Phase: Initial slow growth period. - Cell elongation and expansion. Growth percentage:
