Cellular Characters,Tissues Phylogeny and Life Cycles Kingdom Plantae Cellular Characters,Tissues Phylogeny and Life Cycles

What is a plant? Figure 17.1c-0 Key Vascular tissue Spores Pollen Leaf Alga Surrounding water supports alga. Whole alga performs photosynthesis; absorbs water, CO2, and minerals from the water. Flagellated sperm Seed Flagellated sperm Leaf Stem Leaf Stem Roots Roots Fern Stomata; roots anchor plants, absorb water; lignified cell walls; vascular tissue; fertilization requires moisture Stem Roots Moss Stomata only on sporophytes; primitive roots anchor plants; no lignin; no vascular tissue; fertilization requires moisture Figure 17.1c-0 Comparing the aquatic adaptations of Chara, a multicellular green alga, with the terrestrial adaptations of moss, fern, and pine Pine tree Stomata; roots anchor plants, absorb water; lignified cell walls; vascular tissue; fertilization does not require moisture Flagellated sperm Holdfast (anchors alga)

Plantae Photoautotrophs by chloroplasts Cellulose cell walls (a few are absorptive heterotrophs) Cellulose cell walls Locomotion rare Some green algae are flagellated Male gamete is flagellated in many plants multicellular

A Composite Plant Cell Campbell Fig. 31.6

Plant tissues and organs Leaf Stem Root Campbell 31.5

Plant tissues and organs Leaf tissue Upper epidermis Lower epidermis Mesophyll Functions Photosynthesis Gas exchange Campbell 31.5

Plant tissues and organs Campbell 32.4 Guard cells Prevent water loss Control gas exchange

Plant tissues and organs Stem tissue Function Conducts water and nutrients between roots and leaves Vascular bundles- xylem (water) and phloem (sugars) Ground tissue epidermis Campbell 31.6

Plant tissues and organs Campbell 31.7B Root tissue Conducts water and nutrients to/from stems and leaves Vascular tissue- xylem (water) and phloem (sugars) Meristem = growth

Evolutionary History of Plants Figure 17.2a-0 Evolutionary History of Plants Liverworts Nonvascular plants (bryophytes) Origin of land plants (about 470 mya) Land plants Ancestral green alga Mosses 1 Hornworts Lycophytes (club mosses, spike mosses, quillworts) Seedless vascular plants Origin of vascular plants (about 425 mya) 2 Monilophytes (ferns, horsetails, whisk ferns) Vascular plants Gymnosperms Seed plants Origin of seed plants (about 360 mya) Figure 17.2a-0 Some highlights of plant evolution 3 Angiosperms 500 450 400 350 300 Millions of years ago (mya)

17.2 Plant diversity reflects the evolutionary history of the plant kingdom Early diversification of plants gave rise to seedless, nonvascular plants called bryophytes mosses, liverworts, and, hornworts. The seedless vascular plants include ,lycophytes and monilophytes (ferns and their relatives). Student Misconceptions and Concerns  Students often mistakenly conceive of evolution as a deliberate and directed process, in which organisms somehow acquire adaptations out of want or need. This chapter provides good examples of how evolution actually occurs. During the period when plants first moved onto land, the demands of a terrestrial environment selected among the diversity already existing within the various marginal plant species. For example, plants that produced structures that provided some physical support outside of water had an advantage over those without such structures. Plants did not evolve adaptations to address the needs of living on land. Instead, terrestrial adaptations in existing aquatic plants conveyed advantages in this new environment and were therefore favored.  The text identifies charophytes as the algal group most closely related to plants. Students might misinterpret this to mean that modern charophytes were the direct ancestors of plants. Instead, modern charophytes and plants share a common ancestor, but each has been evolving since the lineages diverged. This same confusion occurs when considering the evolutionary history of humans and chimpanzees. Humans and chimpanzees share a common ancestor. Modern humans did not evolve from modern chimpanzees. Although such distinctions may be clear to us as instructors, beginning students with little experience can easily be confused. Teaching Tips  Consider an analogy between a chicken egg and the first seeds to evolve, although the parallels are limited: each consists of a developing embryo enclosed in a water-resistant packet, along with a store of food.  The support provided by many tightly packed mosses is analogous to the collective support of the many fibers of plush carpeting. Each fiber of carpet and each individual moss plant might easily collapse without the support of its neighbor. Active Lecture Tips  Before addressing plant evolution, have your students work in small groups and list the demands of living on land versus in water. Asking them to consider the challenges that plants faced when they moved onto land prepares them for the discussion of the resulting adaptations in Chapter 17. In part, we all are made curious by such exercises to learn what we figured out on our own!

17.2 Plant diversity reflects the evolutionary history of the plant kingdom Gymnosperms have naked seeds that are not produced in special chambers and include ginkgo, cycad, and conifer species. Angiosperms evolved at least 140 million years ago, are flowering plants, and include flowering trees and grasses. Student Misconceptions and Concerns  Students often mistakenly conceive of evolution as a deliberate and directed process, in which organisms somehow acquire adaptations out of want or need. This chapter provides good examples of how evolution actually occurs. During the period when plants first moved onto land, the demands of a terrestrial environment selected among the diversity already existing within the various marginal plant species. For example, plants that produced structures that provided some physical support outside of water had an advantage over those without such structures. Plants did not evolve adaptations to address the needs of living on land. Instead, terrestrial adaptations in existing aquatic plants conveyed advantages in this new environment and were therefore favored.  The text identifies charophytes as the algal group most closely related to plants. Students might misinterpret this to mean that modern charophytes were the direct ancestors of plants. Instead, modern charophytes and plants share a common ancestor, but each has been evolving since the lineages diverged. This same confusion occurs when considering the evolutionary history of humans and chimpanzees. Humans and chimpanzees share a common ancestor. Modern humans did not evolve from modern chimpanzees. Although such distinctions may be clear to us as instructors, beginning students with little experience can easily be confused. Teaching Tips  Consider an analogy between a chicken egg and the first seeds to evolve, although the parallels are limited: each consists of a developing embryo enclosed in a water-resistant packet, along with a store of food.  The support provided by many tightly packed mosses is analogous to the collective support of the many fibers of plush carpeting. Each fiber of carpet and each individual moss plant might easily collapse without the support of its neighbor. Active Lecture Tips  Before addressing plant evolution, have your students work in small groups and list the demands of living on land versus in water. Asking them to consider the challenges that plants faced when they moved onto land prepares them for the discussion of the resulting adaptations in Chapter 17. In part, we all are made curious by such exercises to learn what we figured out on our own!

Alternation of Generations sporophyte Diploid (two of each chromosome) Produces haploid spores or gametes by meiosis Sporangium- produces spores Spores- haploid cells that develop into haploid multicellular adults gametophyte Haploid (one of each chromosome) Produces gametes by mitosis

THE PLANT LIFE CYCLE Key Haploid (n) Diploid (2n) Figure 17.3-1-5 THE PLANT LIFE CYCLE Key Haploid (n) Diploid (2n) Gametophyte plant (n) Sperm (n) Egg (n) Spores (n) Meiosis Fertilization Figure 17.3-1-5 Plant life cycle (step 5) Zygote (2n) Sporophyte plant (2n)

multicellular seaweed Green Algae Caulerpa Volvox multicellular seaweed Campbell Fig. 16.25C unicellular, colonial algae Gametophyte usually dominant Spirogyra

Mosses Campbell 17.5

A Moss Life Cycle Key Haploid (n) Diploid (2n) Male gametangium Sperm Figure 17.3-2-5 A Moss Life Cycle Key Haploid (n) Diploid (2n) Male gametangium Sperm Female gametangium Egg Gametophyte plants (n) Spores (n) Sporangium Sporophyte Fertilization Figure 17.3-2-5 Moss life cycle (step 5) Zygote Meiosis Gametophyte

Fern compare Campbell Fig. 17.6

A Fern Life Cycle Gametophyte plant (n) Key Haploid (n) Diploid (2n) Figure 17.3-6-5 A Fern Life Cycle Gametophyte plant (n) Key Haploid (n) Diploid (2n) Male gametangium Spores Sperm Female gametangium Egg Mature sporophyte Meiosis Fertilization Zygote New sporophyte growing from the gametophyte Figure 17.3-6-5 Fern life cycle (step 5)

Gymnosperms

Longitudinal section of ovulate cone Sporangia Figure 17.5a-0 Longitudinal section of ovulate cone Sporangia Figure 17.5a-0 Male and female pine cones Longitudinal section of pollen cone

Animation: Pine Life Cycle

Angiosperms Figure 17.10

Pollen grains (n) (male gametophytes) Anther Figure 17.7-5 Pollen grains (n) (male gametophytes) Anther 1 Meiosis 3 Stigma Egg within a female gametophyte (n) Pollen grain 2 Pollen tube Meiosis Ovary Sporophyte (2n) Ovule containing female sporangium (2n) Ovule Sperm Germination Figure 17.7-5 Life cycle of an angiosperm (step 5) 7 Seeds Food supply 6 Fertilization Fruit (mature ovary) Seed coat 4 Key Zygote (2n) Haploid (n) Diploid (2n) 5 Embryo (2n) Seed

Cellular Characters, Diversity and Ecological Roles Kingdom Fungi Cellular Characters, Diversity and Ecological Roles

Fungi Hyphae Mycelium Dikaryotic Fruiting body Life cycle Lichens Athlete’s foot Candida albicans Ringworm

Fungi entirely absorptive heterotrophs lack flagella haploid or dikaryotic nuclei in coenocytic hyphae thin, numerous hyphae give large surface area lack flagella except gametes of some chytrid fungi chitinous cell walls

Fungal Hypha Campbell Fig. 17.15B

Types of Fungi Growth forms of Fungi: molds, or mycelia - yeasts mushrooms - rusts,mildews lichens (with algae) Absorptive heterotrophs decomposers, parasites, mutualists

Fungi life cycle Figure 17.18B

unicellular growth form of fungi Yeast - Fungi unicellular growth form of fungi

Bread Mold Life Cycle Campbell Fig. 17.17B

A Mutualism: Mycorrhizae Campbell Fig. 17.17C

Mushroom Campbell Fig. 17.17E many mushrooms are fruiting bodies of mycorrhizae

Lichen Mutualism Campbell Fig. 17.20B fungal mycelium algal cells cyanobacteria OR green algae, with fungi

More Lichens National Geographic (blueberries, too)

Fungi you don’t want! Campbell 17.19C Corn Smut Athletes foot Ringworm

Fungi you don’t want! Candida albicans Candida growing in the Grows normally in digestive tract Normally controlled by intestinal bacterial Bacterial imbalance lets it grow Symptoms-lethargy, diarrhea, constipation, depression Treatment -diet change and medication monitoring Candida growing in the esophagus

Fungi you do want! Cheeses-Roqufort bleu cheese Truffles- fruiting bodies of mycorrhizal fungi Mushrooms Brewers yeast Antibiotics-Penicillin (Penicillium)