Chapter 29: Seedless Plants

What is the order of the evolution of land plants?

Green algae --> charophytes --> land plants

What is the link between green algae and land plants?

Charophytes

What issues did plants have to overcome on land?

Water loss and protection from the sun

Who helped colonize the land?

Fungi

What are the two major clades of green algae?

Charophytes and Chlorophytes

What are Charophyte's?

It is green algae that never made it to land

What are Chlorophytes?

Sister to all land plants

Describe land plants.

- Have multicellular haploid and diploid stages
- Trend towards more diploid embryo protection
- Trend toward smaller haploid stage

What adaptation protected plants from desiccation?

A waxy stomata and cuticle

What does stomata do?

Stomata opens and closes to limit water loss

What does an closed stomata mean?

Temperatures are too hot

How do plants move water through the plant?

Through tracheids

What type of plants have tracheids?

Tracheophytes

What are the two types of transport tissues in vascular plants?

Xylem and Phloem

What does the Xylem do?

Transports water and dissolved minerals upward from the roots

What does the Phloem do?

Transports sucrose(food) and hormones throughout the plant.

The shift from a _________ haploid generation to a _________ diploid generation:

Dominant

Are humans diplontic or haplontic?

diplontic

What is the multicellular diploid stage called?

Sporophite

How many haploid spores are after the diploid mother cells undergo meiosis?

4 haploid spores

What is the multicellular haploid stage called?

Gametophyte

How do spores divide in the haploid stage?

Mitosis

When gametes fuse during fertilization, a(n) ________ is produced.

Zygote

Haplodiplontic Life Cycle

All land plants Haplodiplontic? True or False.

True

What are two examples of haplodiplontic land plants?

Moss and Angiosperm

What is an angiosperm?

Any plant that flowers

Describe Moss.

- Large gametophyte
- Small, dependent sporophyte

Describe Angiosperm.

- Small, dependent gametophyte
- Large sporophyte

Who are the closest living descendants of land plants?

Bryophytes

Why are bryophytes call nontracheophytes?

They lack tracheids

What type of relationship do bryophytes have that enhances water uptake?

Mycrorrhizial relationship. (Symbiotic relationship between fungi and plants)

Bryophytes have three clades with approximately _________species.

16,000

What are the three clades of bryophytes?

- Liverworts
- Mosses
- Hornworts

Who dominates in Bryophytes?

Gametophytes

What are the characteristic of the gametophyte and sporophyte of a Bryophyte plant?

Gametophyte - conspicuous and photosynthetic
Sporophytes - small and dependent

Describe Liverworts.

Have flattened gametophytes with liverlike lobes
- 80% look like mosses
Form gametangia in umbrella-shaped structures
Also undergo asexual reproduction

Describe Mosses.

Gametophytes consist of small, leaflike structures, areound a stem-like axis.
- Not true leaves - no vascular tissue
Anchored to substrate by rhizoids

What is a female gametangia called?

Archegonia - contains the egg

What is a male gametangia called?

Antheridia - contains the sperm

Life Cycle of Moss

Describe Hornworts.

Origin is puzzling - no fossils until Cretaceous
Sporophyte is photosynthetic
Sporophyte embedded in embedded in gametophyte tissue
Cells have a single large chloroplast

What was the first vascular land plant called and when did it appear?

Cooksonia, which appeared about 420 MYA. It had no roots or leaves & was homosporus (only produced one type of spore)

What are tracheophytes?

Vascular plants

What are the three clades of tracheophytes?

- Lycophytes
- Ptetrophytes
- Seed Plants

Describe Stems.

- Early fossils reveal stems but no roots or leaves
- Lack of roots limited early tracheophytes

Describe Roots.

-provide transport and support
-lycophytes diverged before true roots appeared

Describe Leaves.

- Increase surface area for photosynthesis
- Evolved twice

What is a Lycophyll?

A singular vein

What is a Euphyll?

A branched vein

Describe a Seed?

- Highly resistant
- Contain food supply for young plant
- Lycophytes and Ptetrophytes do not have seeds
- Fruits in the flowering plants(angiosperms) add a layer of protection to seeds and attract animals that assist in seed dispersal, expanding potential range of the species

Describe Lycophytes.

- Worldwide distribution
- Lack seeds
- Superficially resemble true mosses
- Sporophyte dominant

Describe Ptetrophytes.

Phylogenetic relationships among ferns and their relatives is still being sorted out
Common ancestor gave rise to two clades
- whisk ferns and horsetails
All form antheridia and archegonia
All require free water for flagellated sperm

Describe whisk ferns.

Found in tropics
Sporophyte consists of evenly forking green stems without true leaves or roots
Some gametophytes develope elements of vascular tissue
- only one known to do so

Describe Horsetails.

All 15 living species are homosporous
Constitute a single genus, Equisetum
Sporophyte consists of ribbed, jointed photosynthetic stems that arise from branching rhizomes with roots at nodes
Silica deposits in cells -scouring rush

What is the most abundant group of seedless vascular plants?

Ferns with about 11,000 species

Where did coal form and about how many years ago?

Formed from forests about 300 MYA

Describe the Sporophyte and gametophyte of Ferns.

Gametophyte - conspicuous and photosynthetic
Sporophytes - small and dependent (FIX)

How is a ferns life cycle different from moss?

- Much greater development, independence, and dominance of the ferns sporophyte.
- Gameophyte lacks vascular tissue

Life cycle of a fern

True or false. Sporophytes do not have rhizomes.

Fasle

What are fiddleheads?

Fronds(leaves) that are tightly coiled that develop at the tip of the rhizome.

Diploid spore mother cells in sporangia produce haploid spores by meiosis. True or False.

True

Distinctive sporangia in clusters on the back of fronds are clalled?

sori

Today's land plants most likely evolved from a form of _______ called a charophyte.

Green algae

All of the following phyla belong to the Gymnospers except:
A. Cyadophyta
B. Gnetophyta
C. Coniferophyta
D. Ginkophyta
E. Lycophyta

E

Non-vascular plants...
A. Lack roots, stems, and leaves
B. Are tall plants
C. Produce pollen

A

Kingdom Plantae is a clade comprised of bryophytes and what other group?

Tracheophytes

The substance in horsetail stems that makes them suitable for scouring is...

silica

When spores are released from the underside of the fern frond, they fall to the ground where they germinate, growing into:

Haploid Gametophytes

Which of the following is not a characteristic of all plants?
A. They carry out photosynthesis
B. They are eukaryotes
C. They are heterotrophs
D. They are autotrophs
E. They are multicellular organisms

C

Which of the following is not true of fronds?
A. They are synonymous with leaves
B. They number among the largest leaves on the planet
C. They represent the gametophyte generation of ferns
D. They produce sori on their undersides
E. New fronds grow from rhizomes

B

When you see a fern, the large plant you are looking at is the:
A. gametophyte
B. antheridium
C. endosperm
D. sporophyte
E. rhizoid

D

Mosses produce sperm during the _______ stage.

gametophyte

A ______ is an example of a nonvascular plant
A. Maiden hair-fern
B. Liverwort
C. Red Pine
D. Rose

B

The so-called fern allies [relatives of ferns] include several divisions of plants related to ferns. Which of the following belongs to this group?
A. Hornworts
B. Liverworts
C. Club Mosses
D. Lichens
E. Tree Ferns

C

What is the dominant generation in ferns?

Sporophyte

What seedless vascular plant grows in the RGV?

Fern

What does a seed contain?

Embryo, food supply, protective coat

What bryophyte grows in the RGV?

Moss

What is a haplodiplontic life cycle?

Multicellular diploid and haploid phases

What was the trend for the dominant generation in plants?

For sporphytes to dominate