CHAPTER 29 PLANT DIVERSITY I: HOW PLANTS COLONIZED LAND. Section A: An Overview of Land Plant Evolution

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1 CHAPTER 29 PLANT DIVERSITY I: HOW PLANTS COLONIZED LAND Section A: An Overview of Land Plant Evolution 1. Evolutionary adaptations to terrestrial living characterize the four main groups of land plants 2. Charophyceans are the green algae most closely related to land plants 3. Several terrestrial adaptations distinguish land plants from charophycean algae

2 Items referring to physiological processes are limited to photosynthesis, cellular respiration, transpiration, growth, and reproduction.

3 Know these for the EOC Roots, stems, leaves Flowers, fruits, cones, seeds Meristem, cambium, ground, dermal, vascular, xylem, phloem Stomata, guard cells,

4 The pattern of plant growth depends on the location of meristems. Cambium is the lateral meristem. These tissues are where mitosis, and therefore growth, occurs. Fig

5 1. Evolutionary adaptations to terrestrial living characterize the four main groups of land plants There are four main groups of land plants: bryophytes, pteridophytes, gymnosperms, and angiosperms. The most common bryophytes are mosses. The pteridophytes include ferns. The gymnosperms include pines and other conifers. The angiosperms are the flowering plants.

6 Fig. 29.1

7 2. Charophyceans are the green algae most closely related to land plants What features distinguish land plants from other organisms? Plants are multicellular, eukaryotic, photosynthetic autrotrophs. Land plants have cells walls made of cellulose and chlorophyll a and b in chloroplasts. However, several algal groups have cellulose cell walls and others have both chlorophylls.

8 In most land plants, the epidermis of leaves and other aerial parts is coated with a cuticle of polyesters and waxes. The cuticle protects the plant from microbial attack. The wax acts as waterproofing to prevent excessive water loss. Fig

9 All land plants show alternation of generations in which two multicellular body forms alternate. This life cycle also occurs in various algae. However, alternation of generation does not occur in the charophyceans, the algae most closely related to land plants.

10 One of the multicellular bodies is called the gametophyte with haploid cells. Gametophytes produce gametes, egg and sperm. Fusion of egg sperm during fertilization form a diploid zygote. and Fig. 29.6

11 Mitotic division of the diploid zygote produces the other multicellular body, the sporophyte. Meiosis in a mature sporophyte produces haploid reproductive cells called spores. A spore is a reproductive cell that can develop into a new organism without fusing with another cell. Mitotic division of a plant spore produces a new multicellular gametophyte.

12 Which of the structures in the diagram below identifies this cell as a plant cell rather than an animal cell?

13 Unlike animal cells, plant cells have a large central vacuole. How does a vacuole support plant structures? A. It fills with liquid, creating pressure that helps to support the cell. B. It releases materials into the air that decrease the weight of the cell. C. It contains genetic information that controls the activities of the plant. D. It forms a rigid substance called cellulose that supports the plant.

14 A sedge is a grasslike plant with fibrous roots, which are small, shallow roots that branch out from the base of the plant. Which of the following best explains how the structure of the roots helps the plant? A. The plant gets its support from the roots, which serve as a kind of anchor. B. The roots transport water between the stems and leaves of the plant. C. The plant uses its roots to capture water that is close to the surface of the soil. D. The roots allow for the exchange of gases the plant needs for photosynthesis.

15 Plants are composed of different organs, tissues and cells. Which are found only in vascular plants? A. Gametes and leaves B. Xylem and phloem C. Stomata and guard cells D. Flowers and spores