SECONDARY GROWTH ADDS GIRTH TO STEMS AND ROOTS IN WOODY PLANTS
2 LATERAL MERISTEMS VASCULAR CAMBIUM – PRODUCES SECONDARY XYLEM (WOOD) CORK CAMBIUM – PRODUCES A TOUGH COVERING THAT REPLACE EPIDERMIS EARLY IN SECONDARY GROWTH BARK – OUTSIDE THE VASCULAR CAMBIUM, INCLUDES THE PHLOEM, VASCULAR AND CORK CAMBIUM
CONCEPT 35.5 GROWTH, MORPHOGENESIS, AND DIFFERENTIATION PRODUCE THE PLANT BODY
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IT IS THE CELL EXPANSION THAT ACCOUNTS FOR THE ACTUAL INCREASE IN PLANT MASS MORPHOGENESIS – DEVELOPMENT OF BODY FORM AND ORGANIZATION PATTERN FORMATION – THE DEVELOPMENT OF SPECIFIC STRUCTURES IN SPECIFIC LOCATION
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PLANT HORMONES ABSCISIC ACID – MAKES SURE SEENDS DON’T GERMINATE TOO EARLY, INHIBITS CELL GROWTH, AND STIMULATES THE CLOSING OF THE STOMATA AUXIN – LEADS TO ELONGATION OF STEMS AND PLAYS A ROLE IN PHOTOTROPISM AND GRAVITROPISM
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CYTOKININS – PROMOTE CELL DIVISION AND LEAF ENLARGEMENT, SLOWS DOWN AGING OF LEAVES ETHYLENE – INITIATES FRUIT RIPENING AND CAUSES FLOWERS AND LEAVES TO DROP (ASSOCIATED WITH AGE) GIBBERELLINS – ASSISTS IN STEM ELONGATION, INDUCES THE GROWTH OF DORMANT SEEDS, BUDS, AND FLOWERS