Module 3 Diversity

Final exammmm!

What is a tracheophyte?

A vascular plant

What are the four main groups of tracheophytes?

Lycophytes, gymnosperms, ferns, angiosperms

What are the synapomorphies of vascular plants?

Sporophyte is independent and long-lived
Sporophyte is branched with multiple sporangia
Lignin in secondary cell walls
Sclerenchyma
Vascular tissue
An endodermis

Roots

What is a dichotomous sporophyte?

The apical meristem splits into two and divides into two branches of equal length

What is a pseudomonopodial sporophyte?

The apical meristem divides equally, but one branch remains dominant

What is lignin?

A complex polymer of phenolic compounds which is deposited in secondary cell walls in some cells. It adds strength and rigidity to the walls.

What are sclerenchyma?

Non-conductive cells with thick, lignified secondary cell walls (typically with pits) which are dead at maturity.

What are two kinds of sclerenchyma?

Fibers and sclereids

What is the purpose of sclerenchyma?

To add structure and support, and for sclereids alone maybe to deter herbivory

What are tracheary elements?

Elongate cells which are dead and maturity with secondary cell walls which make up the xylem

What are two kinds of tracheary elements?

Tracheids and vessel members

What are sieve elements?

Elongate cells with only a primary cell wall with specialized pores in sieve areas which make up the phloem

What are the two kinds of sieve elements?

Sieve cells, sieve tube members

What is a stele?

A spatial arrangement of xylem and phloem

What kind of vascular tissue do early vascular plants have?

Prostele - a central solid cylinder of xylem and phloem

What is the cortex?

Parenchyma tissue between the vascular tissue and the epidermis

What is the endodermis?

A cylinder of cells in roots and some stems surrounding the vascular tissue which allows selective control of solute passage from the outside

What is the hallmark of the endodermis?

The casparian strip

What is a Casparian strip?

A band of lignin and suberin in the cell wall of the endodermis

What make up the roots?

Apical meristem, protective root cap, endodermisk-bound vascular cylinder, and root hairs

When were the first vascular plants dated to?

Fossil record: 430-420 Ma
Molecular data: 450-420 Ma

What did the first vascular plants look like?

They were a few cm in height with dichotomous branching, a prostele, the stems were upright with a horizontal rhizome, they had no true roots or leaves, they had terminal sporangia with trilete spores and were homosporous.

What are two examples of extinct vascular plants and what did they look like?

Rhyniophytes and Zosterophyllophytes which were small, leafless, dichonomously branched with terminal sporangia, and had tracheids

What is Cooksonia?

An extinct rhyniophyte and hte oldest vascular plant fossil ever found

Which of the extinct vascular plants is ancestral to Lycophytes?

Zosterophyllophyta

How are the sporangia of Zosterophyllophyta arranged?

In a lateral position

What are the three lycopodiophyta?

Lycopodiaceae, Selaginellaceae, Isoetaceae

What are the synapomorphies of Lycopodiophyta?

More complex root/stem structures

Lycophylls/Microphylls

Protosteles

Sporangia at or near axils of microphylls

Sporangia often grouped into strobili

What is a strobilus?

Sporangia grouped into cones

What is the enation theory?

That lycophylls/microphylls evolved from enations (outgrowths of main stem that lack vascular tissue which eventually had vascular tissue thread into them)

What does the Lycophyte vascular system look like?

They have protoxylem and metaxylem mixed together in the center of the stem kinda brainlike lookin’

What are three living Lycophytes?

Club mosses (Lycopodiaceae)

Spike mosses (Selaginellaceae)

Quillworts (Isoetaceae)

What are the hallmarks of club mosses?

No ligule associated with microphyll

Homosporous

Four families represented in NZ

Strobilus of sporangia on sporophylls (spore-bearing lycophyll)

What are the synapomorphies for selaginellaceae and isoetaceae?

Heterospory

Ligule associated with leaf

What are the hallmarks of Selaginellaceae?

Ligules on sporophylls

Heterosporous

Endosporic gametophyte development

What does heterosporous mean?

They make two kinds of spores: mega and microspores

What are the hallmarks of Isoetaceae?

They have microphylls

Heterosporous

Fleshy underground stem (Corm)

Aquatic

What are the synapomorphies of Euphyllophyta?

Sporangia are terminal on lateral branches, longitudinally dehiscent

The shoot has euphylls

The chloroplast genome has a 30kB DNA inversion

What are Trimerophytes?

An extinct euphyllophyte lineage, ancestral to vascular plants with megaphylls and a monopodial habit

What is a monopodial habit?

A main stem with smaller side branches

What is the telome theory of leaf formation?

That leaves (Megaphylls) formed from overtopping, planation, and webbing. Basically, the umbel looking branching went lateral and then tissue webbed out between some of the smaller branches to make a leaf

What are the synapomorphies of Monilophyta?

Stem protoxylem mesarch

Siphonostele

What is a siphonostele?

A stele with a central pith, ring of xylem or arranged ring of xylem, and phloem to the outside

What is a Eustele?

A type of stele with distinct vascular bundles surrounding a pith. Each bundle is xylem to the inside, phloem to the outside.

What is an Atactostele?

A stele where the vascular bundles are just buckshot throughout the stem

In which early vascular plant group do we see siphonosteles with no leaf gaps?

Selaginella, because they still have microphylls

What early vascular plant group has a Siphonostele with leaf gaps?

Ferns, they have megaphylls

Which early vascular plant group has a eustele?

Seed plants

What three plant types fall under Monilophytes?

Ferns, whisk ferns, and horsetails

What is the most speciose group after angiosperms?

Monilophytes

What plant group has the highest known chromosome number?

Monilophytes

How are Monilophytes classified into groups?

Based on the type of sporangium

What are the two kinds of sporangia found in Monilophytes?

Eusporangia - found in the more primitive ferns as well as in the lycopods - and Leptosporangia - found only in leptosporangiate ferns

Which ferns are Leptosporangiate?

Polypod ferns, tree ferns, heterosporous ferns, schizaeoid ferns, gleichenioid ferns, filmy ferns, osmundaceous ferns

Which ferns are Eusporangiate?

Marattioid ferns, ophioglossid ferns, whisk ferns, horsetails

What are the hallmarks of a Eusporangia?

They form from several initial cells (Multicellular origin)

Rounded and sac-like with no stalk

Several cell layers, no annulus

Many spores produced

What are the hallmarks of a Leptosporangia?

They form from one initial cell (Unicellular origin)

Rounded, usually with a stalk

One cell layer, annulus present

Few spores produced

What is an annulus?

The outer layer of a Leptosporangia made up of one layer of cells which cracks open at the lip cells at maturity and HOONS the spores

What are the synapomorphies of Esquitales?

Stems with ribbed canals

Leaves reduced and whorled

Sporangiophore

Spores with elaters

What are the hallmarks of Equisetum (horsetail, scouring rush)

Distinctive ribbed & jointed stems

Homosporous

Grow in river margins, lake edges, swampy ground

High silica content

Extensive underground rhizome

Noxious

What are the synapomorphies of Psilotales (whisk ferns)

Leaves reduced

Roots lost

Synangium with bifid appendage

What is the synapomorphy for Ophioglossales?

Leaf with sterile and fertile segments

What are the parts of fern fronds?

Pinna, pinnule, primary pinna, secondary pinna

True or False: A rhizome can be a trunk

True. It’s those funky fresh ferns again

What is a sorus?

A cluster of sporangia

What is an indusium?

A flap of tissue that covers leptosporangia until maturity

What is a false indusium?

Where the margin of the frond rolls over to cover the sporangia

Where is the archegonia on a prothallus?

At the top, near the heart shape

Where are the antheridia on a prothallus?

Towards the bottom tip of the heart shape

Do prothalluses have rhizoids?

Yes

What are the hallmarks of Hymenophyllales (Filmy ferns)?

Sensitive to dessication

Sori found at the frond margin covered by a tube or flap-shaped indusia

What are the hallmarks of Gleicheniales (forking ferns)

Distinctive branching of frond

No indusium

How can you tell something is a member of Schizaeles?

Their fertile fronds look different from their non-fertile fronds

What are the heterosporous ferns?

The water ferns like Azolla rubra

What are the two subgroups of Cyatheales (tree ferns)?

Dicksoniaceae & Cyatheaceae

What are the hallmarks of Dicksonia ferns?

Fronds harsh to touch

Sori at pinnae margins

Indusium present

Hairs on fronds and rhizome

What are the hallmarks of Cyathea?

Fronds soft to touch

Sori at centre of pinnae

Scales on frond and rhizome

What are some examples of Polypod ferns?

Pteridaceae, Aspleniaceae, Blechnaceae, Polypodaceae, Notogrammitis, Zealandia pustulata, Pyrrosia elagnifolia

Does Pteridaceae have an indusium?

It has a false indusium

What’s funky about Aspleniaceae sori?

They’re elongated, often in a herringbone pattern and have an indusia

What’s groovy about Blechnaceae?

It has distinct sterile and fertile fronds where the fertile ones look dead

What’s neat about Polypodaceae?

Naked sori, epiphytic mostly, and they have creeping rhizomes

What’s hip about Notogrammitis?

Naked sori, irregular, and they have a short creeping rhizome