Chapter 27 Seedless Plants Flashcards
Common ancestor of all land plants
Green algeae
Green algae and plants share many ____ and ___ traits
Green algae and plants share many biochemical and metabolic traits
Plants are complex multicellular eukaryotes with:
- Cellulose cell walls
- Chlorophylls a and b in plastids
- Starch as a storage product
- may have cells with two anterior flagella
Unlike green algae, all land plants develop from:
Multicellular embryos enclosed in maternal tissues
Waxy cuticle
Prevents plant tissues from dying out
Stomata
Allow gas exchange through the cuticle
Gametangia
Plant sex organs which have a layer of non-reproductive cells that protects the gametes
Antheridium
Male gametangia
Archegonium
Female gametangia
Plant life cycles have a ___ gametophyte stage and a ___ sporophyte stage
Plant life cycles have a haploid gametophyte stage and a diploid sporophyte stage
Antheridia
Male gametangia that form sperm cells
Archegonia
Female gametangia that bears a single egg
Archaeplastids
- Red algae
- Green algae
- land plants
Four major plant groups
- Bryophytes (nonvascular plants)
- Seedless vascular plants
- Gymnosperms
- Angiosperms
Mosses and other bryophytes rely on ___ and __ to obtain needed materials, which restricts their ___
Mosses and other bryophytes rely on diffusion and osmosis to obtain needed materials, which restricts their size
Mosses and other bryophytes do not form ___
Mosses and other bryophytes do not form seeds; they reproduce and disperse primarily via haploid spores
Vascular plants have two types of vascular tissues:
- Xylem
2. Phloem
Xylem
Conducts water and dissolved minerals
Phloem
Conducts dissolved organic molecules, such as sugar
Vascular plants include
- Seedless vascular plants
- Gymnosperms
- Flowering plants
A key step in evolution of vascular plants was the ability to produce ___
A key step in evolution of vascular plants was the ability to produce lignin
Seedless vascular plants reproduce and disperse primarily via ___
Seedless vascular plants reproduce and disperse primarily via spores
gymnosperms
reproduce by forming unprotected seeds on a stem or in a cone
Angiosperms
reproduce by forming seeds enclosed within a fruit
Angiosperms are ___ ___
Angiosperms are flowering plants
Bryophytes
The only living nonvascular plants
Typically small
Only plants with a dominant gametophyte generation-sporophytes remain permanently attached
Three phyla of bryophytes
- Bryophyta (mosses)
- Hepatophyta (liverworts)
- Anthocerophyta (hornworts)
Mosses usually live in denses ___ or ___
Mosses usually live in dense colonies or beds
Mosses have rhizoids
Tiny hairlike absorptive structures
Mosses are important for:
- Forming soil
- commercially (sphagnum)
- form peat bogs used for fuel
The dominant phase of the moss life cycle is the ___
The dominant phase of the moss life cycle is the gametophyte (haploid)
The moss sporophyte is completely dependent upon the ___ for its nutrition (mosses)
The moss sporophyte is completely dependent upon the gametophyte for its nutrition
The sporophyte is responsible for producing ___ (mosses)
The sporophyte is responsible for producing spores (mosses)
Liverworts
Body form is a thallus, not differentiated into leaves, stems, or roots
Hairlike ___ on the underside of the ___ anchor plants to the soil (liverworts)
Hairlike rhizoids on the underside of the thallus anchor plants to the soil
Liverworts lack
Liverworts lack stomata, although some have surface pores analogous to stomata
Liverwort life cycle
Basically the same as that of mosses
Some gametangia are borne on stalked structures
Some liverworts reproduce ___ by forming tiny balls of tissue called ___
Some liverworts reproduce asexually by forming tiny balls of tissue called gemmae
gemmae
asexual buds inside the gemmae cups
Fossils indicate that ___ were probably the first group of plants to arise from the common plant ancestor
Fossils indicate that bryophytes were probably the first group of plants to arise from the common plant ancestor
The oldest plant fossils resemble ___ in many respects
The oldest plant fossils resemble liverworts in many respects
Seedless vascular plants
Have true stems with vascular tissues - most with true roots and leaves
___ Are the main organs of photosynthesis
Leaves are the main organs of photosynthesis
Two classes of seedless vascular plants:
- Club Mosses
2. Ferns
Ferns include
horsetails and whisk ferns
Ferns
A monophyletic group - the closest living relatives of seed plants
Club mosses
Small, evergreen plants with true roots; rhizomes and erect aerial stems; microphylls
Club moss sporangia
Borne on reproductive leaves
Club mosses are common where?
n temperate woodlands
___ is an organic material formed from remains of ancient vascular plants, particularly those of the ___ period
Coal is an organic material formed from remains of ancient vascular plants, particularly those of the Carboniferous period
Ferns are mostly ___ plants with a dominant ___ generation and ___ roots
Ferns are mostly terrestrial plants with a dominant sporophyte generation and true roots
Ferns have Rhizomes
Sporophyte which has a horizontal underground stem
Fern rhizomes bear fronds which are what?
complex comound leaves
Fern fronds ___ from the ground tightly ___. This is called ___
Fern fronds emerge from the ground tightly coiled. This is called fiddlehead’s
The fern life cycle alternates between the dominants, ___ and the ___
The fern life cycle alternates between the dominants, diploid sporophyte and the haploid gametophyte
Fern spore production occurs in ___ on __ of the ___
Fern spore production occurs in sori on fronds of the sporophyte
Ferns have ___ sperm cells which swim from an ___ to the neck of a ___ through a thin film of water on the ground underneath the ___
Ferns have flagellate sperm cells which swim from an antheridium to the neck of an archegonium through a thin film of water on the ground underneath the prothallus
Some Ferns and club mosses are ___
Some Ferns and club mosses are Heterosporous
Homospory
Production of only one type of spore as a result of meiosis
Homospory is characteristic of
- Bryophytes
- Horsetails
- Whisk Ferns
- Most ferns and club mosses
Heterospory
Produce two types of spored
Heterospory is the forerunner of ___
Heterospory is the forerunner of the evolution of seeds
Certain ___ and ___ exhibit heterospory
Certain ferns and club mosses exhibit heterospory
Each strobilus bears two kinds of sporangia:
- Microsporangia
2. Megasporangia
Microsporangia
Produce microsporocytes, which undergo meiosis to form microscopic, haploid microspores and then develop into male gametophytes
Megasporangia
produce megasporocytes which undergo meiosis to form haploid megaspore and then develop into female gametophyte
