Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter 20 Lecture Outline Introduction to the Plant Kingdom: Bryophytes Luminous Moss

 REVIEW Binomial System of Nomenclature? Largest Group? Smallest Group? Species being defined most by what?

Outline  Introduction– Plant Characteristics Alternation of Generation  Introduction to the Bryophytes  Phylum Bryophyta – Mosses  Human and Ecological Relevance of Bryophytes

INTRODUCTION  PLANTS = Land Plants & Green Algae  Plant Characteristics Photosyntheic Pigments: ________________ Energy stored as ______________ Cell walls made of ______________ Mitosis w/ phragmoplasts & _________ Telophase Green Algae

Introduction …  Green Algae vs. Land Plants– primitiveness? Land Plants evolved from _____________ in water.  LAND PLANTS 1 st land plant fossils = 400 Million years ago –  so Evolved earlier

Introduction-Land Plants …  TYPES BRYOPHYTES: Primitive – Have No: ________________ 23,000 FERNS & RELATIVES: Less Primitive: Have ________ 12,000 GYMNOSPERMS: Complex Have: ________________ 700 ANGIOSPERMS: Most Complex Have: _____________ 250,000

Introduction– LAND PLANTS …  1 st Land Survival Characteristics Leaves with: Multicellular organs for making reproductive cells: – Gametangia: make __________ o Antheridia o Archegonia Archegonia of moss Antheridia of moss

1 st Land Characteristics … Multicellular organs … _________ - Sporangia Egg + Sperm = Zygote = 1 st cell of embryo – Develops into ___________ while held within ___________

 Alternation of Generation: Sexual Reproduction in plants Sexual Reproduction – Mitosis & Meiosis – Sexual Reproduction Criteria: parents: type cell division: meiosis fertilization: – 1N cells: have ½ the normal # of DNA – 2N cells: have normal # of DNA

HUMAN LIFE CYCLE « ADULT HUMAN = 2N OVARY ZYGOTE TESTES MEIOSIS 1N EGGS 1N SPERM FERTILIZATION

Alternation of Generation … 1N generation alternates with the 2N generation Characteristics 1. Sporophyte: o 2N Adult o Produces: o Organ used = o Cell division type = 2. Gametophyte o 1N Adult o Produces: o Organ used = o cell division type

Alternation of Generation … Characteristics … 3. Spores grow into what adult plant? ______________ 4. Eggs & Sperm do what process? ______________ o Creating = _____________ o The ______ grows  ___________ 5. Primitive Plants have Gametophyte generation Dominant 6. Primitive Plants are mostly Monecious:

HUMAN LIFE CYCLE « ADULT HUMAN = 2N OVARY ZYGOTE TESTES MEIOSIS 1N EGGS 1N SPERM FERTILIZATION

Alternation of Generation … Diagram of 2N Sporophyte Sporangia 2N Zygote FERTILIZATION Spore Mother Cells MEIOSIS 1N Eggs 1N Sperm 1N Spores MITOSIS Archegonia Antheridia 1N Gametophyte

Introduction to the Bryophytes  Bryophytes = Group which includes 3 Phyla: Mosses, Liverworts, and Hornworts Phylum Bryophyta = moss

Introduction to the Bryophytes …  Need for Water:  Vascular Tissue: NONE Most water absorbed: Specialized Cells to move fluids – Hydroids: – Leptoids: Moss Sperm

Phylum Bryophyta – Mosses Interesting Types—Luminous Moss  Classes: 3 – Peat mosses – True mosses – Rock moss A true moss Peat Moss Rock Moss

Phylum Bryophyta – Mosses …  Structure Gametophytes – Blades: o Cells with chloroplasts. – Axis: o Often with central strand of hydroids - Rhizoids:

Gametophyte Structure …  Reproductive Structures: Gametangia – Location – Archegonium o Shape o Venter in swollen base contains egg o Neck w/ narrow canal. - To attract sperm: – Paraphyses multicellular filaments scattered among archegonia.

– Antheridia on short stalks, surrounded by walls one cell thick. – Sperm Paraphyses

Phylum Bryophyta – Mosses …  Sexual reproduction: – Sperm forced out top. Archegonia release: Sperm swim: Fertilization Zygote = 1 st cell of Sporophyte

SPOROPHYTE Embryonic Sporophyte grows into spindle-shaped embryo. Mature sporophyte Seta Foot Capsule

Capsule of Sporophyte Function: Calyptra: Top of archegonium splits off and stays on top of sporophyte Operculum Peristome, composed of one or two rows of teeth, under operculum at tip of capsule. Function:

Spores Spores develop into filamentous protonema that produces buds that develop into leafy gametophytes.

Phylum Bryophyta – Mosses  Sexual reproduction:

Human and Ecological Relevance of Bryophytes  Pioneer species: Example: bare rock after volcanic eruptions Help form organic matter in soil  Ground Cover:  Indicators of surface water  Packing material  Peat mosses most important Soil conditioner Poultice material: is antiseptic Fuel

Review  Introduction  Introduction to the Bryophytes  Phylum Bryophyta – Mosses  Human and Ecological Relevance of Bryophytes

END

Phylum Hepaticophyta – Liverworts  8,000 species  Structure and form: Most common and widespread liverworts have flattened, lobed thalli (singular: thallus).

Phylum Anthocerophyta – Hornworts  Structure and form 100 species