Lecture Exam 1 - #4

BIOLIO

300,000 living species

Plants have diversified into roughly… how many species?

Terrestrial ancestors

Land plants have what kind of ancestors?

Photosynthetic protists (algae)

Land plants do not include…

Supply oxygen

Plants _____ and are the ultimate source of most food eaten by land animals

1. Eukaryotic

2. Photoautotrophs

3. Multicellular

4. Alternation of generations

5. Starch

6. Chlorophyll a and b, flavonoids to absorb harmful UV radiation

Plantae Characteristics (6)

Bryophytes (non-vascular)

Most related to starting ancestors

Starting Cycle

Seaweed → land (bryophytes) → Tissues (ferns) → Seeds (gymnosperm) → Flower (angiosperm)

Charophytes (green algae)

Closest relative of land plants

Nuclear and chloroplast

Comparisons of what types of genes point to charophytes as the closest living relatives of land plants.

Embryophytes

Plants with embryos

1. Alternation of generations and multicellular, dependent embryos

2. Walled spores produced in sporangia

3. Multicellular gametangia

4. Apical meristems

Derived Traits of Plants (4)

Non-vascular: Bryophyta, anthocerophyta, hepatophyta

First plants…

Archegonia

Female reproductive structure - produce eggs

Antheridia

Male reproductive structure - produces sperm

Gametophyte, mitosis

____ is haploid and produces haploid gametes by _____.

Sporophyte, meiosis

Fusion of the gametes results in a diploid _______, which produces haploid spores by _____.

• No conductive tissue

  • No roots or stems

  • Rely on diffusion/osmosis to move nutrients

• Need water for reproduction

Traits of non-vascular plants: (4 points)

Extant Lineages - 10 phyla

Still have a living member left, not only extinct ones

Vascular Tissue

Tissue that moves water and nutrients

Nonvascular plants (bryophytes)

Utilize diffusion, resulting in small plants

Spores

Reproductive cells that can develop into a new haploid organism without fusing with another cell. Mitotic division results in new multicellular gametophyte

1. Phylum Bryophyta - mosses

2. Phylum Hepatophyta - liverwort (marchantia)

3. Phylum Anthocerophyta - hornworts

Non-vascular plants = bryophytes, dominant stage is gametophyte

Mosses help retain nitrogen in the soil - capable of living in diverse/extreme environments, most common in moist forests and wetlands.

The ecological and economic importance of mosses

Peat

Sphagnum forms extensive deposits of partially decayed organic material - used as a source of fuel.

Sphagnum

Important global reservoir of organic carbon… over harvesting could release stored CO2 to atmosphere

Sporophyte

Consists of sporangium, seta, footSp

Sporangeous tissue, archesporium

Mass of fertile, spore-forming cells. Located between the columella and the cell wall layers. Called?

1. Phylum Lycophyta (club mosses, spike mosses) (has unbranched vascular tissue)

2. Phylum Monilophyta (ferns) (homosporous)

Seedless Vascular Plants, Sporophyte = dominant stage

Sporophyll Leaves

Modified leaves that bear sporangia that produce haploid cells via meiosis

Homosporous spore production

Sporangium on sporophyll results in single type of spore which is bisexual gametophyte resulting in the egg or sperm.

Heterosporous Spore production

Megasporangium on megasporophyll = megaspore → Female gametophyte (egg)

Microsporangium on microsporophyll = microspore → Male gametophyte (sperm)

Strobili

Clusters of sporophylls

• Archegonia

• Antheridia

• Rhizoids

Fern Gametophyte (Prothallus (heart)) has what three features?

1. Gingkophyta

2. Cycadophyta

3. Gnetophyta

4. Coniferophyta

Gymnosperms (4)

Anthophyta

Angiosperm phylum

Gymnosperms

“naked seed” plants, not enclosed in chambers (like ovaries) … utilize cones and sporophyll (spore-bearing appendages)

Angiosperm

Flowering plants are called:

1. Nonvascular (3 phylum)

2. Gingkophyta

3. Cycadophyta

Motile sperm phylums