Transcript Nonvascular Plants

Nonvascular
(Hepatophyta, Bryophyta, Anthocerotyphyta)
Nonvascular Plants
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Definition: Any of various plants that lack vascular
tissue; a bryophyte
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Around 25,000 species of bryophytes all together
Bryophytes used to be all the different types of nonvascular
plants now it just includes moss
Hepatophyta includes liverworts
Anthocerotophyta includes hornworts
Nonvascular plants are plants that do not use a system
of vessels to transport water and nutrients between
different parts of the plant
Bryophytes
(Mosses)
Classifications
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There are 8 classes of moss
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Takakiopsida
Sphagnopsida
Andreaeopsida
Andreaeobryopsidea
Oedipodiopsida
Polytrichopsida
Tetraphidopsida
Bryopsida
Important Facts
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Approximately 12,000 species of moss
Mosses are nonvascular and do not have roots meaning that then need moist
environments so that water can be absorbed directly into the cells of the
gameophyte
In northern latitudes, the north side of trees and rocks will have more moss
than others
In the south, it’s the opposite
Fossil records of moss are sparse
Recovered as early as the Permian in Antarctica and Russia
A moss plant body has no roots and has tiny cellular threads that serve as
anchors
The structures on moss look like a leaf although the "leaves" of the moss are
only thin sheets of cells, usually a single layer
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The leaf like structures will curl up and dry out when water is unavailable and
then revives when they obtain water
Obtain energy through photosynthesis
Description
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Small, soft plants usually around
1-10 cm (0.4-4 in) tall
Commonly grow close together
either in clumps or mats
Mostly in damp or shady
locations
Produce spore capsules that
may appear as beak-like
capsules on thin stalks
Are distinguished by their
multicellular rhizoids
Rhizoids-structure that
functions like a root in support
or absorption
Life Cycle
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Begins with a haploid spore
Spore germinates to produce a protonema
 Protonema is either a mass of thread-like filaments of flat
 Usually looks like a thin green felt and mainly grows on stable surfaces
 damp soil, tree bark, rocks, concrete or other
From the protonema grows the gametophore
 (gamete-bearer)
 A single mat of protonemata can develop several gametophores which is what causes
clumps of moss
The tips of the gametophore stems or branches develop sex organs
 Female organs (archegonia)-small flask-shaped clumps of cells with an open neck
that the male sperm swims down
 Male organs (antheridia)-enclosed by modified leaves called perigonium
Mosses can either be dioicous or monoicous
Life Cycle 2
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Diocious- Male and female sex organs are on different gametophyte
plants
Monoicous or autoicous- both male and female sex organs are on
the same plant
When there is water, the sperm swim from the antheridia to the
archegonia and fertilization occurs creating a diploid sporophyte
 Sperm has two flagellae the aid in propulsion
The immature sporophyte pushes its way out the archegonial venter
 Takes about a quarter to half a year for the sporophyte to
mature
The sporophyte then develops a capsul and a operculum which are
then sheathed by the remaing archegonial venter
Inside the capsule, spore producing cells undergo meiosis
to form haploid spores so the process can start over again
Life Cycle Diagram
Asexual Reproduction
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In some kinds of moss such as Ulota phyllantha,
leaves or bits of the stem which break off and
form new plants without fertilization
This means all units are genetically identical
Habitat
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Mosses are normally found in areas that are damp and have low
amounts of light
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Some types of moss have adapted and are only found in cities
Some types of moss are completely aquatic
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Common in wooded areas and near streams
Also found in cracks in damp city streets
Inhabiting bogs, marshes, and slow moving waterways
Some types are semi-aquatics
Wherever mosses are they require moisture
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Small size
Lack of tissue and cuticule
Need of liquid for fertilization
Why is moss important?
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Supplies food and shelter for small animals and
insects
Protect soil
Keeps slopes from washing away during severe
weather or storms
Help form new soil
Anthocerotyphyta
(Hornworts)
Classifications
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Leiosporocerotopsida
Anthicerotopsida
Description
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Get their name from their horn shaped pore
capsule
Grow as a sheet of green tissue
Without sporophytes present they are
10 to 20 mm in length
Have no leaves or stem
Attached to ground by rhizoid
The plant body of a hornwort—the haploid
gametophyte stage—usually grows thin rosette
like or ribbon-like
Between one and five centimeters in diameter
Description Cont.
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Each cell in a hornwort usually contains just one
chloroplast
In most species of hornworts, the chloroplast is fused
with other organelles to form a large pyrenoid
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Pyrenoids are the centers of carbon dioxide fixation within
the chloroplasts of algae and hornworts that both
manufactures and stores food
The pyrenoids manufacture and store food
This is unusual in land plants, but very common in
algae
Reproduction
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Reproduction in hornworts is the same as in moss
The spores germinate into protonema which grows into
a gametophore
The gametophore then develops sex organs on the
branches
The antheridia then swims down the archegonia and
fertilization occurs
A diploid sporophyte then grows and the sporophyte
develops a capsule with a spore inside
Inside the spore meiosis happens so the cycle can begin
again
Habitat
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Hornworts can be found worldwide, but they usually
grow only in places that are damp or humid
Species can grow as weeds in gardens or fields
Large tropical or subtropical species such as
Dendroceros can be found on trees
Hornworts are usually in the submersed plant
community
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Since they lack roots they can drift to various water levels to
find nutrients
Tolerant of cool temperatures and low light levels
Hepatophyta
(Liverworts)
Classifications
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Marchantiopsida
Jungermanniopsida
Haplomitriopsida-newly recognized class
Important Facts
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6000 to 8000 species
Some species grow flattened and leafless called thallus
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Many thallus liverworts live on the surface of water
Most species however grow in a leafy form
The first liverworts were found 400,000,000 years ago
during the Devonian Era
Named a liverwort because the people that found them
felt that the arrangement of cells on the surface was
similar to cells from actual animal livers
Description
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Small, ranging from 2-20 mm
A flat, branching ribbon shaped plant that
resembles the lobes of a liver
Many different shapes of liverwort leaves:
undivided, variously-lobed, divided into hair-like
segments, or two lobes of unequal size
Often used as indicators of the habitat condition
Asexual Reproduction
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Certain species of liverworts
produce vegetatively
Liverworts contain bowlshaped structures call cupule
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Cupule holds gemmae which
looks like little green eggs
Raindrops splash gemmae
onto the ground
If the gemmae lands in a
hospitable environment then
it will develop rhizoids and
produce liverworts
Reproduction
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Same as moss and
hornworts
Archegonial receptacle
from below with
capsules filled with
spores
Spores will be released
and if the conditions are
right then the spores will
germinate
Life Cycle of Liverworts
Habitat
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Mainly in deeply shaded,
moist areas
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Such as under shrubs or plants
Most common in the
Northern Hemisphere
Must be moist and have a
source of water
Some liverworts are aquatic
and can live on the surface of
water
Desert species can tolerate
direct sunlight and total
desiccation
Works Cited
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http://www.mainevolunteerlakemonitors.org/mciap/herbarium/
Hornworts.php
http://www.teara.govt.nz/en/liverworts-and-hornworts/3
http://www.hiddenforest.co.nz/bryophytes/difference.htm
http://www.essortment.com/all/mossplant_rmir.htm
http://en.wikipedia.org/wiki/Hornwort#Life_cycle
http://www.anbg.gov.au/bryophyte/classificationliverworts.html
http://www.backyardnature.net/liverwrt.htm
http://dermnetnz.org/dermatitis/plants/liverwort.html
http://creationwiki.org/Hepatophyta