Domain Eukarya:Kingdom Plantae

Seedless vascular plants

Seedless vascular plants

What traits are new in this groupof plants?

Ferns and other seedless vascular plants formed the first forests

Vascular tissue enhanced transportAnd favored erect growth

Vascular tissue internal tubes that transportwater (xylem)

nutrients (phloem)

Lignin is an organic polymer (wood)strengthens cell walls of the xylem

Shoot and root systems improvedgrowth, support and photosynthesis

Other traits that appear in vascular plants

• Life cycles switched todominant sporophytestiny gametophytes

• Thicker waxy cuticle

• Fully functional stomata

Phylum Lycophyta (club mosses, spike mosses and quillworts)

Most primitive group of vascular land plants

During the carboniferous period, there were lycophytes that were about 120 feet tall.

Thrived in moist swamps, but became extinct when the climate got drier

Phylum LycophytaToday’s lycophytes grow on tropical trees.

Lycophytes have sporangia clustered into club-shaped cone (strobilus)

Some species are homosporous (one type of spore)

And others are heterosprous (two types of spores)

Phylum LycophytaThe genus Selaginella includes familiar species such as the Resurrection Plant

(Selaginella lepidophylla)

the most diverse genus of which is Lycopodium.

Phylum Pterophyta (ferns, horsetails and whisk ferns)Ferns and horsetails grew along side lycophytes during the Carboniferous.

This is a diverse group, with more than 11,000 species, second only to the flowering plants in variety.

They are all homosoprous, with spronagia on sorus or strobilus

The most familiar pteridophytes are the ferns.

Phylum Pterophyta: FernsMost of them grow in the tropics.

Ferns have large leaves (called fronds)

They underside of fronds have dots called sori, which contain many sporangia

Life cycle of the ferns has a dominant sporophyte

Sporangia are stalked with spring like devicesthat catapult spores

Spore gives rise to a heartshaped gametophyte that is bisexual

The sprophyte sprouts From the notch of the heart

Gametophyte shrivels and dies after the youngsporophyte detaches itself.

Phylum Pterophyta: HorsetailsName refers to the brushy appearance of the stems.

They were very diverse in the Carboniferous, today only 15 species remainAll are in the genus Equisetum

Stems have joints. Small leaves emerge from each joint.

Stem is the main photosynthetic organ.

At the tip of the stem are the strobili with sporangiathat produce spores

Phylum Pterophyta: whisk fernNo tissue differentiation between roots and shoots.

Lack leaves

Each yellow knob on a stem consists of three fused sporangia.

Ecological and Economic Importance of PterophytesThe evolution of vascular tissue, roots and leaves accelerated

photosynthesis rates.

These Carboniferous forests removed CO2 to such degree that it

caused global cooling and the spread of glaciers.

Their remains of these plants formed thick deposits of organic matter.

Pressure and heat gradually converted them to coal.

Today coal is mined and burned

to generate much of the electricity.

Trends in Seedless vascular plants

Which generation is the dominant one?

Which generation grows on top of the other one?

Why are these plants not totally adapted to dry land?

What are the key differences between seedless vascular plants and the nonvascular plants?

All gametophytes are _____. haploid a myth dreamed up by biology professors to confuse students diploid single-celled female, but not male, reproductive structures

The diploid generation of the plant life cycle always _____. produces spores is called the gametophyte develops from a spore is larger and more conspicuous than the haploid stage produces eggs and sperm

Plants undergo alternation of generations in which _____. the vascular generation alternates with the nonvascular generation the sporophyte generation alternates with the gametophyte generation male gametes alternate with female gametes male plants alternate with female plants all of these occur

In mosses gametes are produced by _____; in ferns gametes are produced by _____. mitosis ... mitosis binary fission ... mitosis meiosis ... mitosis meiosis ... meiosis mitosis ... meiosis

The noticeable part of a fern plant is a _____.diploid gametophyte haploid sporophyte haploid gametophyte diploid sporophyte

The innovation essential to the survival of mosses on land was _____.freedom from the need for water to reproduce the retention of the embryo on the parent plant chlorophyll vascular tissue flowers