tailieunhanh - Lecture Biology (6e): Chapter 35 - Campbell, Reece
Chapter 35 - Plant structure and growth. This chapter compare structures or cells; explain the phenomenon of apical dominance; distinguish between determinate and indeterminate growth; describe in detail the primary and secondary growth of the tissues of roots and shoots; describe the composition of wood and bark; distinguish between morphogenesis, differentiation, and growth; explain how a vegetative shoot tip changes into a floral meristem. | CHAPTER 35 PLANT STRUCTURE AND GROWTH Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A1: The Plant Body 1. Both genes and environment affect plant structure 2. Plants have three basic organs: roots, stems, and leaves With about 250,000 known species, the angiosperms are by far the most diverse and widespread group of land plants. As primary producers, flowering plants are at the base of the food web of nearly every terrestrial ecosystem. Most land animals, including humans, depend on plants directly or indirectly for sustenance. Introduction Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings A plant’s structure reflects interactions with the environment on two time scales. Over the long term, entire plant species have, by natural selection, accumulated morphological adaptations that enhance survival and reproductive success. For example, some desert plants have so reduced their leaves that the stem is actually the primary photosynthetic organ. This is a morphological adaptation that reduces water loss. 1. Both genes and environment affect plant structure Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Over the short term, individual plants, even more than individual animals, exhibit structural responses to their specific environments. For example, the submerged aquatic leaves of Cabomba are feathery, enhancing the surface area available for the uptake of bicarbonate ion (HCO3-), the form of CO2 in water. Leaves that extend above the surface form oval pads that aid in flotation. The architecture of a plant is a dynamic process, continuously shaped by the plant’s genetically directed growth pattern along with fine-tuning to the environment. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Even faster than a plant’s structural responses to environmental changes are its physiological (functional) adjustments. Most plants are rarely exposed to severe drought and | CHAPTER 35 PLANT STRUCTURE AND GROWTH Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A1: The Plant Body 1. Both genes and environment affect plant structure 2. Plants have three basic organs: roots, stems, and leaves With about 250,000 known species, the angiosperms are by far the most diverse and widespread group of land plants. As primary producers, flowering plants are at the base of the food web of nearly every terrestrial ecosystem. Most land animals, including humans, depend on plants directly or indirectly for sustenance. Introduction Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings A plant’s structure reflects interactions with the environment on two time scales. Over the long term, entire plant species have, by natural selection, accumulated morphological adaptations that enhance survival and reproductive success. For example, some desert plants have so reduced their leaves that the stem is actually the primary .
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