Transcript Botany Ch20_Mosses lecture-2015

Chapter 20
Lecture Outline
Luminous Moss
Introduction to the
Plant Kingdom:
Bryophytes
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

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
Green Algae
•
Photosyntheic Pigments: ________________
•
Energy stored as ______________
•
Cell walls made of ______________
•
Mitosis w/ phragmoplasts & _________
Introduction …

Green Algae vs. Land Plants– primitiveness?
•

Land Plants evolved from _____________ in water.
LAND PLANTS
•
1st 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 …
1st Land Survival Characteristics

•
Leaves with:
•
Multicellular organs for making reproductive cells:
–
Gametangia: make __________
o
Antheridia
o
Archegonia
Archegonia
of moss
Antheridia
of moss
1st Land Characteristics …
Multicellular organs …
• - _________
Sporangia
Egg + Sperm = Zygote
•
•
–
= 1st 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:
Moss Sperm

Vascular Tissue: NONE
•
Most water absorbed:
•
Specialized Cells to move fluids
–
Hydroids:
–
Leptoids:
Phylum Bryophyta – Mosses
Interesting Types—Luminous Moss

Classes: 3
–
Peat mosses
Peat Moss
–
True mosses
–
Rock moss
A true moss
Rock Moss
Phylum Bryophyta – Mosses …

Structure
•
Gametophytes
–
Blades:
o
–
Axis:
o
-
Cells with
chloroplasts.
Often with central
strand of hydroids
Rhizoids:
Gametophyte Structure …

Reproductive
Structures:
•
Gametangia
–
Location
–
Archegonium
o
o
o
Shape
Venter in
swollen base
contains egg
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 = 1st 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