Seedless Plants

Seedless Plants

  • Monophyletic - descended from a single common ancestor.

  • Synapomorphy - developed from embryos - embryophytes

  • Chlorophylls a & b, Starch as a storage product, Cellulose in cell walls.

Glaucophytes:

  • Unicellular,

  • freshwater organisms

  • Contain small amount of peptidoglycan b/w inner & outer membrane

Red Algae: Division Rhodophyta

  • Multicellular, marine organisms with red pigments called phycoerythrins, and other accessory pigments phycocyanin, and carotenoids, which allow them to absorb light at greater depths.

  • Used to make thickness in foods.

  • Example: Porphyra (Nori), Rhodymenia sp.

Green Algae:

  • Photosynthetic organisms

  • Cytoplasm of adjacent cells connected through plasmodesmata

Chlorophytes:

  • Largest clade of green algae

  • Chlamydomonas → single celled green algae

  • Reproduce sexually or asexually

  • Found → soil, freshwater, oceans, even snow

  • Green algae are mostly freshwater organisms, with chlorophyll a and b pigments, and store excess carbohydrates as starch.

  • Example: Volvox, Chlorella

Volox:

  • forms spherical colonies

  • two flagella, type of locomotion → rolling motion

  • colonies are photosynthetic

  • found → freshwater environments

  • cellular differentiation

    • Less cellular differentiation → colonial

    • More cellular differentiation → multicellular.

Oedogonium:

  • long, unbranched filaments composed of cylindrical cells.

  • contains one or more chloroplasts

  • reproduces both sexually and asexually

    • Sexual Rep: Sperm from Antheridum fertilizes an egg from an oogonium. Produces a diploid zygote which → meiosis produce haploid zoospores. The swim around → settle → undergo mitosis → form new filament.

Alternation of Generation:

Spores & Gametes are haploid.

Spores are produced by meiosis.

Gametes are produced by mitosis.

Ulva:

  • Also known as sea lettuce, it is a multicellular green alga with a sheet-like thallus structure.

Chara:

Non-Vascular Plants:

  • Simple plants that lack specialized tissues for conducting water and nutrients, typically found in moist environments.

  • Form paraphyletic group

  • Example: Mosses (Bryophyta), Liverworts (Marchantiophyta)

Liverworts: Division Marchantiophyta

  • Liverworts are nonvascular plants

  • small, leafy, or thalloid plants.

  • leaf-like thallus.

  • lack cuticle, true roots, stems, and leaves (vascular system) not true stomata, but they have unicellular rhizoids (type of roots) that anchor them to the substrate and absorb water and nutrients.

  • Provide habitat and food for various organisms

  • Reproduce

    • Asexually through gemmae cups

    • Sexually through the production of spores.

    • The sporangium in the mature sporophyte contains spores and elater

Ex - Marchantia

Mosses: Division Bryophyta

  • Small, herbaceous plants, grow in moist environments because they dry out very quickly.

  • Leafy stems and leaf-like structures called gametophytes.

  • Lack vascular system (true roots, stems and leaves)but have true stomata, have multicellular rhizoids

  • Retain moisture, preventing soil erosion, and providing habitat for various organisms.

  • Flourished → swampy forest of Carboniferous period → gave rise to large deposits of coal.

  • reproduce

    • asexually through fragmentation

    • sexually through production of spores.

Ex - Mnium

Hornworts: Division Anthocerotophyta

  • small, horn-shaped plants, grow in damp environments.

  • body structure with a flattened, ribbon-like thallus.

  • lack Vascular system (true roots, stems, and leaves), have true stomata, have unicellular rhizoids

  • Hornworts also have a symbiotic relationship with cyanobacteria, which help fix nitrogen from the atmosphere.

  • Reproduce

    • asexually through production of gemmae

    • sexually through production of spores.

Seedless Vascular tissue:

  • 2 types of vascular tissue in plants → xylem and phloem.

    • Xylem transports water and minerals from the roots to the rest of the plant. Provide support as cell wall contains lignin.

    • Phloem transports sugars and other organic compounds from the leaves to other parts of the plant.

  • Tracheids evolved in the sporophytes of early vascular plants and is therefore a synapomorphy for vascular plants

Ex - Pteridium Moss (Mnium) vascular tissue

Lycophytes: Division Lycophyta

  • small, herbaceous plants

  • reproduce through spores.

  • have true roots, stems, and leaves, unique vascular system → xylem and phloem

  • Include clubmosses and spike mosses.

Monilophytes: Horstails and Ferns

Horsetails: Division Tracheophyta

Ferns: Division Tracheophyta

Fern Prothalim: Haploid With sporophyte: Diploid