bio lecture 3

Vocabulary flashcards covering major terms related to plant evolution, algal relatives, and key adaptations for life on land.

Embryophytes

Land plants; clade Embryophyta; embryos develop and are protected within parental tissues; includes mosses, ferns, and seed plants.

Bryophytes

Nonvascular land plants (mosses, liverworts, hornworts); lack true vascular tissue; life cycle often dominated by the gametophyte.

Mosses

A group of bryophytes; nonvascular, usually found in moist environments.

Liverworts

A group of bryophytes; example genus Marchantia polymorpha.

Hornworts

A group of bryophytes; nonvascular land plants.

Ferns

Vascular, seedless land plants (pteridophytes); sporophyte generally prominent; require water for fertilization.

Angiosperms

Flowering plants; seeds enclosed within fruits.

Gymnosperms

Seed plants with naked seeds, often in cones; no fruit enclosing the seed.

Vascular plants

Plants with xylem and phloem for transport; includes ferns, gymnosperms, and angiosperms.

Zygnematophyceae

Class of green algae believed to be closest relatives of land plants; may be single-celled or filamentous; often isogamous with no plasmodesmata.

Coleochaetophyceae

Group of charophyte algae; part of the lineage closely related to land plants.

Charophyceae

Stoneworts; a group of green algae (Charophyta) linked to land plant ancestry.

Charophytes

Green algae within Streptophyta; includes Coleochaetophyceae and Charophyceae; sister group to land plants.

Streptophytes

Clade that includes land plants and some green algae; shares features like phragmoplasts and plasmodesmata.

Viridiplantae

Green plants; includes Chlorophyta (green algae) and Streptophyta (land plants and related algae).

Phragmoplast

Microtubule-based structure guiding cell plate formation during plant cell cytokinesis.

Oogamy

Reproductive system with a large nonmotile egg and a small motile sperm.

Plasmodesmata

Cytoplasmic channels through plant cell walls enabling cell-to-cell communication and transport.

Apical growth

Growth at the tips of shoots and roots (apex) for elongation.

Multicellularity

Organisms composed of multiple cells; a key feature in land plant evolution.

Uniaxial growth

Growth along a single axis, often at tips (apical).

Sporopollenin

Durable polymer in spore and pollen walls; resists desiccation and decay.

Cuticle

Waxy protective layer coating the epidermis of aerial parts; reduces water loss.

Stomata

Pores in leaf surfaces that regulate gas exchange; opened/closed by guard cells.

Mycorrhizae

Mutualistic association between plant roots and fungi that aids nutrient uptake.

Ectomycorrhiza

Fungi form a sheath around root tips (mantle) and exchange nutrients outside root cells.

Arbuscular mycorrhiza

Fungi penetrate root cortical cells and form tree-like arbuscules to exchange nutrients.

Archegonium

Female gametangium; produces eggs and houses embryo after fertilization.

Antheridium

Male gametangium; produces sperm.

Gametangia

Organs that enclose and protect gametes in plants.

Gametophyte

Haploid multicellular stage that produces gametes via mitosis.

Sporophyte

Diploid multicellular stage that produces spores via meiosis.

Sporangium

Structure that produces spores in the sporophyte.

Spore

Haploid reproductive cell that can grow into a gametophyte.

Alternation of generations

Life cycle with both haploid (gametophyte) and diploid (sporophyte) multicellular stages.

Stoneworts

Common name for Charophyceae; a group of freshwater green algae related to land plants.

Chara

Genus of stoneworts (Charophyceae); often used as a model for life cycle studies in related plants.