Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings PowerPoint ® Lecture Slides for Essential Biology, Second Edition & Essential Biology with Physiology Neil Campbell, Jane Reece, and Eric Simon Presentation prepared by Chris C. Romero CHAPTER 16 Plants, Fungi, and the Move onto Land Figures 16.1 – 16.5

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Some giant sequoia trees weigh more than a dozen space shuttles Flowering plants such as corn, rice, and wheat provide nearly all our food

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings A mushroom is probably more closely related to humans than it is to any plant Every 2 seconds humans destroy an area of tropical rain forest equal to the area of 3 football fields

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Coniferous forests are highly productive BIOLOGY AND SOCIETY: THE BALANCING ACT OF FOREST CONSERVATION –They provide lumber for building and wood pulp for paper

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Our demand for wood and paper is so great that clear-cut areas have become commonplace Figure 16.1

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The loss of coniferous forests –Threatens the trees and other organisms that live in forests –Can be minimized by conservation practices

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Plants COLONIZING LAND –Are terrestrial organisms –Are multicellular eukaryotes that make organic molecules by photosynthesis

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Living on land poses different problems from living in water Terrestrial Adaptations of Plants Structural Adaptations –Plants require structural specializations –Roots and shoots

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 16.2 Plant Leaf performs photosynthesis Cuticle reduces water loss; stomata allow gas exchange Shoot supports plant (and may perform photosynthesis) Alga Surrounding water supports the alga Whole alga performs Photo- synthesis; absorbs water, CO 2, and minerals from the water Roots anchor plant; absorb water and minerals from the soil (aided by fungi)

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Most plants have mycorrhizae, symbiotic fungi associated with their roots Figure 16.3

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Leaves –Are the main photosynthetic organs of most plants –Have stomata for gas exchange –Contain vascular tissue for transporting vital materials Figure 16.4

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Other types of vascular tissue are found in the roots and shoots of plants

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Plants produce their gametes in protective structures called gametangia Reproductive Adaptations

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings In plants, but not algae, the zygote develops into an embryo while still contained within the female parent

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 16.5 Ovary of flower Embryo Maternal tissue

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The Origin of Plants from Green Algae The move onto land and the spread of plants to diverse terrestrial environments were incremental

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Molecular comparisons and other evidence place a group of green algae called charophyceans closest to plants Figure 16.6

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The history of the plant kingdom is a story of adaptation to diverse terrestrial habitats PLANT DIVERSITY

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Highlights of Plant Evolution The fossil record chronicles four major periods of plant evolution

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 16.7 Cenozoic Mesozoic Paleozoic Charophyceans (a group of green algae) Bryophytes (e.g., mosses) Seedless vascular plants (e.g., ferns) Gymnosperms (e.g., conifers) Angio- sperms Origin of plants Early vascular plants First seed plants Diversification of flowering plants

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The first period –Was the origin of plants from their aquatic ancestors, charophyceans The second period –Was the diversification of vascular plants

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The third period –Began with the origin of the seed The fourth period –Was the emergence of flowering plants, or angiosperms

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Bryophytes Mosses Figure 16.8 –Are the most familiar bryophytes

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Mosses display two key terrestrial adaptations –A waxy cuticle that helps prevent dehydration –The retention of developing embryos within the mother’s gametangium

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Mosses have two distinct versions of the plant –The gametophyte, which produces gametes –The sporophyte, which produces spores Figure 16.9

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The life cycle of a moss exhibits an alternation of generations

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure Spores n Mitosis Sporophyte 2n Mitosis Gametes (sperm and eggs) n Fertilization Zygote 2n Mitosis Spore capsule Meiosis Gametophyte n Haploid Diploid

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Ferns Figure –Are seedless vascular plants

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings During the Carboniferous period, about 290–360 million years ago, ferns formed swampy forests that covered much of what is now Eurasia and North America –These forests formed what would become fossil fuels Figure 16.12

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Gymnosperms A drier, colder climate at the end of the Carboniferous period favored the evolution of gymnosperms, the first seed plants

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Conifers –Cover much of northern Eurasia and North America –Are usually evergreens, which retain their leaves throughout the year Figure 16.13

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Conifers and most other gymnosperms have three terrestrial adaptations Terrestrial Adaptations of Seed Plants –Further reduction of the gametophyte –The evolution of pollen –The advent of the seed

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The first adaptation is a greater development of the diploid sporophyte compared to the haploid gametophyte generation

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure Gametophyte (n) Sporophyte (2n) (a) Sporophyte dependent on gametophyte (e.g., mosses) Sporophyte (2n) Gametophyte (n) (b) Large sporophyte and small, independent gametophyte (e.g., ferns) Sporophyte (2n) Gametophyte (n) (c) Reduced gametophyte dependent on sporophyte (seed plants) Haploid (n) Diploid (2n)

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings A pine tree of other conifer is actually a sporophyte with tiny gametophytes living in cones Figure 16.15

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings A second adaptation of seed plants to dry land was the evolution of pollen A pollen grain –Is actually the much-reduced male gametophyte –Fertilizes the female gametophyte

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The third terrestrial adaptation was the development of the seed A seed consists of a plant embryo packaged along with a food supply within a protective coat Figure Integuments Spore (a) Ovule Haploid (n) Diploid (2n) Pollen tube Pollen grain (male gametophyte) Female gametophyte Egg nucleus Discharged sperm nucleus (b) Fertilized ovule Seed coat (derived from integuments) Food supply (derived from female gametophyte tissue) Spore case Embryo (new sporophyte) (c) Seed

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Angiosperms –Supply nearly all our food and much of our fiber for textiles More efficient water transport and the evolution of the flower help account for the success of the angiosperms

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The dominant stage of the angiosperms is a sporophyte with gametophytes in its flowers Flowers, Fruits, and the Angiosperm Life Cycle

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure Stamen Anther Filament Ovule Petal Carpel Stigma Style Ovary Sepal

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The life cycle of an angiosperm

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Mature sporophyte plant with flowers Germinated pollen grain (male gametophyte) on stigma of carpel Anther at tip of stamen Pollen tube growing down style of carpel Ovary (base of carpel) Embryo sac (female gametophyte) Egg Sperm nuclei Fertilization Endosperm Zygote Embryo (sporophyte) Fruit (develops from ovary) Seed (develops from ovule) Seed Germinating seed Sporophyte seedling Haploid (n) Diploid (2n) Ovule Figure 16.18

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The seed being enclosed within an ovary distinguishes angiosperms from gymnosperms

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings A fruit –Is a ripened ovary –Helps protect the seed and increase seed dispersal –Is a major food source for animals Figure 16.19

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Angiosperms Angiosperms and Agriculture –Supply fiber, medications, perfumes, and decoration Agriculture –Is a unique kind of evolutionary relationship between plants and animals

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Plant Diversity as a Nonrenewable Resource The exploding human population is extinguishing plant species at an unprecedented rate

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Humans depend on plants for thousands of products including food, building materials, and medicines

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Table 16.1

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Preserving plant diversity is important to many ecosystems as well as humans

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Fungi are extremely important to ecosystems because they decompose and recycle organic materials FUNGI

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Fungi –Are eukaryotes, and most are multicellular –Are more closely related to animals than plants

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings A gallery of diverse fungi Figure 16.20

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Characteristics of Fungi In this section, the structure and function of fungi are described

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Fungi are heterotrophs Fungal Nutrition –They digest their food externally and acquire the nutrients by absorption

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The bodies of most fungi are constructed of structures called hyphae Fungal Structure

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The hyphae –Form an interwoven mat called a mycelium –Are separated into cells by cross-walls made mainly of chitin

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure Hyphae Reproductive structure Spore- producing structures Mycelium

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Fungi reproduce by releasing spores that are produced either sexually or asexually Fungal Reproduction

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The Ecological Impact of Fungi Fungi –Have an enormous ecological impact

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Fungi and bacteria Fungi as Decomposers –Are the principal decomposers of ecosystems –Keep ecosystems stocked with nutrients necessary for plant growth

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Molds –Can destroy fruit, wood, and human-made materials

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Of the 100,000 known species of fungi, about 30% make their living as parasites Parasitic Fungi Figure 16.22

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings About 50 species of fungi are known to be parasitic in humans and other animals

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Fungi are commercially important Commercial Uses of Fungi –As food and in baking –In beer and wine production Figure 16.23

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Some fungi produce antibiotics Figure 16.24

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Interdependence between species, or symbiosis, is an evolutionary product EVOLUTION CONNECTION: MUTUAL SYMBIOSIS –Mutualism is symbiosis that benefits both species

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Lichens –Are symbiotic associations between fungi and algae Figure 16.25