Lecture 19 Flashcards
6 Major Charophytecharacteristics
- Phragmoplast
- Branching growth
- Apical Growth
- Oogamy
- Plasmodesmata
- Retention of Egg in archegonium
main lineages of embryophytes
- Chlorophytes
- Streptophytes
novel features of embryophytes
- Embryo: zygote retained, nourished by gametophyte (matrotrophy)
- Cuticle
- Sporopolenin walled spores(decay resistant)
- Antheridia & Archegonia with sterile jacket
- Sporic life cycle
- (Stomata)
types of bryophytes
- Marchantiophyta: Liverworts
- Bryophyta: Mosses
- Anthocerophyta: Hornworts
types of Polysporangiophytes
- Protracheophytes
* Vascular Plants
Bryophyte Characteristics
- Embryo: zygote retained, nourished by gametophyte (matrotrophy)
- Cuticle
- Sporopoleninwalled spores(decay resistant)
- Antheridia & Archegonia with sterile jacket
- Sporiclife cycle
- (Stomata)
- Gametophyte Dominant & Sporophyte Dependent
what kind of life cycle does a bryophyte have
a sporic life cycle
is the gametophyte or sporophyte generation dominant in bryophytes
the gametophyte
is the gametophyte or sporophyte generation dependent in bryophytes
the sporophyte
is water required for fertilization in bryophytes?
yes
what develops in spores in the life cycle of bryophytes?
protonema
protonema
the first stage in development of the gamtophyte of mosses and certain liverworts
describe the gametophyte of bryophytes
Gametophyte: free living and dominant.
describe the sporophyte of bryophytes?
Sporophyte: dependent on gametophyte.
how are spores dispersed in bryophytes
by the wind
do bryophytes require water for fertilization
yes
what is matrotrophy
penetrating to a form of nutrition provided by the maternal gametophyte, such as a moss gametophyte providing nutrients to the zygote and developing sporophyte
describe the matrotophy of bryophytes
gametophyte provides nourishment to developing sporophyte
do bryophytes have true vascular tissue?
no
how is water transported in bryophytes
water transports external via capillary action.
hydroids
elongate transport cells, no lignin, water permeable. (in some mosses)
leptoids
food conducting cells similar to phloem. (in some mosses)
do bryophytes have true leaves
no
true or false, bryophytes have roots
false
what is the function of a rhizoids
attachment
do bryophytes have hydroids and leptoids?
no
what bryophyte phylum do liverworts belong to
marchantiophyta
how many species of liverworts are there
approximately 6000
describe the morphology of a liverworts
- Leafy or…
- Thalus: Undifferentiated tissue.
- Cuticle with pores for gas exchange.
- No stomata.
- Rhizoids for attachment, no absorption.
what kind of environments do liverworts reproduce in?
moist, cool, and shady environments
do liverworts have sexual or asexual reproduction
both
how does asexual reproduction happen in liverworts?
fragmentation and gemmae
do liverworts require water for sexual reproduction?
yes
what is the function of an antheridia
to produce sperm located on the top surface of the disc.
what is the male gametophyte of a liverwort
antheridia
what is the function of an archegonia
to produce eggs
what is the function of the female gametophyte of of liverworts
to make the gametes
what is the female gametophyte of a liverwort
archegonia
bryophyta consists of the ____
mosses
what is the diversity of the bryophytes
- sphagnidae
- andreaeidae
- bryidae
how many species of sphagnidae are there?
less than 400 species
how many species of andreaeidae are there
approximately 100 species
how many species of bryidae are there?
less than 9500 species
what are the morphological types of mosses?
cushiony and feathery
how many cells thick are the leaves of mosses?
one
do mosses have a cuticle with a stomata?
yes, in their sporophyte only
do mosses have rhizoids? why?
for attachment and no absorbtion
does sexual reproduction of mosses require water?
yes
what kind of habitat do mosses reproduce in?
moist (sometimes transistently)
do all mosses have a green gametophyte?
yes
what are the male and female gametophytes of a moss
antheridia and archegonia
do all mosses have a sporophyte?
yes
where are spores made?
in the sporangium
what is the gametophyte morphology of sphagnidae mosses?
Branching Stems, dead leaf cells have high water holding capacity (20x dry wt., cotton 5-6x)
what are the functions of sphagnidae mosses?
- Release H+into environment…forms bogs…
* Antiseptic properties.
how are the spores of sphanidae mosses released?
they are released via explosive operculum
how many species of adreaeidae mosses are there?
100 species
what color are adreaeidae mosses
blackish green and reddish brown
where do adreaeidae mosses grow?
on rocks
describe the structure of protonema of adreaeidae mosses
they contain 2 rows of cells
describe the structure of the rhizoids of adreaeidae mosses
they contain two rows of cells
how many species of bryidae mosses are there?
less than 9500 species
describe the protonema of bryidae mosses
thy are one cell thick
describe the structure of the leaves of bryidae mosses
they are one cell thick
what is the function of hydroids and leptoids in bryidae mosses
internal water transport
do bryidae mosses have stomata?
only in the sporophyte and some only have one guard cell
what are the parts of the sporangium of bryidae mosses
the capsule
the calyptra
the peristome
and the operculum
what is a operculum?
the cap of the sporangium of bryidae mosses
what is a calyptra?
the covering of the sporangium of bryidae mosses
what is a capsule?
the sporangium of bryidae mosses
how are spores dispersed in bryidae mosses
by wind
what is the function of the peristome in bryidae mosses
spore dispersal
what byrophyte phylum do hornworts belong to?
antherocerophyta
how many species of hornworts are there?
aproximately 100
what is the morphology of hornworts?
- Similar to liverworts
- Cuticlewith stomata (sporophyte only)
- Rhizoids for attachment, no absorbtion.
- Single large chloroplast (most species)
- Placenta & meristematicregion at base of sporophyte.
what is the function of hornworts?
they are a host for N-fixing Nostoccyanobacteria.
what kind of reproduction do hornworts have
sexual reproduction
do hornworts require water for sexual reproduciton?
yes
what kind of habitat do hornworts reproduce in?
moist environments
what is the ancestor of bryophytes?
Aglaophyton major
describe Aglaophyton major
- they had no vascular tissue
- they had hydroids and leptoids
- they had terminal sporangia
how did early bryophytes reproduce?
with alternation of Isomorphic generations.
are bryophytes primitive?
- Many bryophytes (mosses) can withstand intense desiccation and recover rapidly upon rehydration.
- Survive Freeze drying!!!
- Few Vascular Plants can.
