Seedless Vascular Plants

What are the major groups of seedless vascular plants?

• Horse tails

• Club mosses

• Whisk ferns

• Ferns

What are equisetum?

Horse tails

What are lycophytes?

Club mosses

What are Psilotum?

Whisk ferns

When did seedless vascular plants dominate the landscape?

350 mya

What type of significance do Seedless vascular plants have?

• Horticultural

• Ecological

How do seedless vascular plants have ecological significance?

• The brake fern removes Arsenic from water and soil

• They form mutualistic relationships

What are other uses of seedless vascular plants?

Fiddleheads are one of the few edible parts of a fern—ostrich fern

What is the leaf of a fern called?

The frond which has leaflets and subleaflets

Example of world wide problem fern?

Lydogium

Example of a mutualistic relationship fern?

Water fern Azolla with cyanobacteria

What are the two apical meristems of vascular plants?

root and shoot

What are the three tissue systems of vascular plants?

• Dermal

• Vascular

• Ground

What primary meristem is for dermal tissue system?

Protoderm

What primary meristem is for ground tissue system?

Ground meristem

What primary meristem is for vascular tissue system?

Procambium

What do vessel elements have that tracheids lack?

perforation plates

What are microphylls?

Simple leaves with one vein down the middle

What are megaphylls?

Leaves with branched veins

What is independent in seedless vascular plants?

Both the gametophyte and sporophyte at maturity

What were the three most important phyla of seedless vascular plants the devonian period?

• Rhyniophyta

• Zosterophyllophyta

• Trimerophytophyta

What is homospory?

The production of only one type of haploid spore

• Can result in separate male and female gameotphytes or bisexual depending on the species

What is heterospory?

The production of two types of spores in two different kinds of sporangia

• Microspores—produced in microsporangia

• Megaspores—produced in megasporangia

Why is heterospory important?

It is the precursor to seeds and pollen

In the production of sperm and eggs, seedless vascular plants are similar to
bryophytes in having both __

Antheridia and archegonia

The sporophyte-gametophyte relationship in seedless vascular plants differ from

both bryophytes and seed plants

In seedless vascular plants, what is larger the sporophyte or gameotphyte

Sporophyte

Rhyniophytes, zosterophytes, and trimerophytes all had __-

branching photoysnthetic stem systems without roots or leaves and underground rhizomes

What was the key transitionary feature of seedless vascular plants

Tracheids

What are the two phyla of living seedless vascular plants

1. Lycopodiophyta (lycophytes)

2. Monilophyta

The first phyla of living seedless vascular plants (lycopodiophyta or lycophytes) contain what

1. Lycopodiacea (club mosses)

2. Selaginellacea (spike mosses)

3. Isoetacea (quillworts)

The second phyla of living seedless vascular plants (monilophyta) contains what

• Psilotopsida (whisk ferns)

• Marattiopsida (small group of tropical ferns)

• Polypodiopsida (true ferns)

• Equisetopsida (horsetails)

How do modern lycophytes compare to extinct lycophytes

Modern lycophytes are small herbaceous plants while ancient lycophytes dominated moist tropical forests during the Carboniferous period

All lycophytes have ___

Microphylls—single leaf vein

Which lycophytes are heterosporous and which are homosporous?

• Lycopodiacea (club mosses)—homosporous

• Selaginellacea (spike mosses)—heterosporous

• Isoetacea (Quillworts)—heterosporous

What is a strobilus>

A reproductive structure that consists of sporophylls at the end of aerial branches

What is a sporophyll?

A specialized leaf-like organ that bears spore producing structures (sporangia)

Where are sporangia found on sporophylls

On the upper surface

In heterosporous members, the gametophyte development is ___

endosporic

What is endospory?

Gametophyte development takes place MOSTLY inside the spore wall

Homospores are __

exosporic

Psilotopsida (whisk ferns) consists of what two orders?

Both homosporous

• Ophioglossales

• Psilotales

The psilotales include which two living genera?

1. Tmesipteris

2. Psilotum (whisk ferns)

What is an epiphyte?

A plant that grows on another plant but is not parasitic?

How do Tmesipteris grow?

As epiphytes

What are enations?

Leaf-like structures that are different from leaves as they lack vascular tissue

How do psilotum (whisk ferns) grow?

Lack true roots and have enations instead of leaves. Homosporous and bisexual gametophytes that are small underground structures

The leaves/fronds of Polypodiopsida are ___

Megaphylls

Most ferns are __

Homosporous

Where do the sporangia of Polypodiopsida occur?

On the lower surface of the leaves

What is a fiddlehead?

The young fern megaphylls that arise from an underground stem termed a rhizome

What is this?

A fern sorus

What is an indusium?

The upside down umbrella structure of fern sori that holds the sporangia

How do the archegonia and antheridia of ferns grow?

Both antheridia and archegonia produce on the same thallus (bisexual) but mature at different times to prevent self-fertilization

• Some species are unisexual

What is an annulus?

A thickened ridge of cells along the back of fern sporangia which aids in spore dispersal

What is sporopollenin?

A substance found in plant spore cell walls to prevent cellular damage

What is a prothallus?

The gametophyte of ferns

What is a rhizome?

horizontal underground plant stem that can produce both shoots and roots

What type of sporous are the water ferns of polypodsidia

heterosporous

What are trichomes?

Extensions of epidermal cells that look like egg beaters

Equistium (horse tails) may be

the oldest survivng genus of plants on earth

What type of sporous is Equistium?

Homosporous

Equisetum are made up of what?

Sporangia are clustered into umbrella-like structures sporangiophores that are grouped together into strobilus

What are the characteristics of the spores of Equisetum?

Spores are wrapped with elongated structures called elaters that uncoil as it matures and dries releasing the spores. Each spore becomes a bisexual gameotphyte photosynthetic

What two tissue types is vacular tissue composed of?

Xylem and phloem

What does xylem carry and to where?

water up through the plant

What does phloem carry and to where?

Carries photosynthate down through the plant

Where can you find vascular tissue in ferns?

In the rhizomes, stem, and leaves

Is there vascular tissue in the fern prothallus/gametophyte?

No; it is green so photosynthetic and thin so no space for vascular tissue

Identify?

Lycopodiacae

Identify

Selaginella

Identify

Selaginella; flattened leaves and third row of leaves on underside

Identify

Psilotopsida

What type of branching is seen in Psilotopsida ?

Dichotomous

Identify?

Equisetopsida; shows two sporophyte forms (vegetative; left, and reproductive; right)

Microphylls can be found in both ___

Lycopodiophyta and Equisetopsida

What type of branching

Dichotomous

What type of branching

Alternate

What type of branching?

Opposite

What type of branching?

Whirled

What type of branching?

Whirled

On what generation do you find rhizomes

Sporophyte

How is a root different from a rhizome

A rhizome is a modified stem that grows horizontally

What is the pinna?

One small subleaf of a fern

What is this?

A fern sorus

How is the gametophyte connected to the ground? How does nutrients move aroun?

Rhizoids; diffusion