Plant Diversity I: How Plants Colonized Land

These flashcards focus on key vocabulary terms related to plant diversity and adaptations for colonizing land.

Cyanobacteria

Simple, single-celled organisms that were among the first to colonize land.

Charophytes

Green algae from which land plants evolved, specifically Zygnematophyceae are the closest living relatives.

Sporopollenin

A durable polymer that prevents drying of zygotes in charophytic algae and protects plant spores.

Alternation of generations

A life cycle pattern with multicellular haploid (gametophyte) and diploid (sporophyte) stages.

Walled spores

Spores that are produced in sporangia, allowing for protection and dispersal.

Gametangia

Multicellular organs in plants that produce gametes; includes archegonia (female) and antheridia (male).

Apical meristem

Regions of actively dividing cells at the tips of plant roots and shoots, responsible for growth.

Cuticle

A waxy covering over the epidermis of plants that prevents water loss and protects from pathogens.

Stomata

Specialized pores in plant leaves that regulate gas exchange and water loss.

Bryophytes

Nonvascular plants, including mosses, liverworts, and hornworts, notable for their dominant gametophyte stage.

Sporophyte

The diploid stage of the plant lifecycle that produces spores through meiosis.

Homosporous

Seedless vascular plants that produce one type of spore.

Heterosporous

Plants that produce two types of spores, leading to gametophytes of different sexes.

Xylem

Vascular tissue responsible for transporting water and minerals in plants.

Phloem

Vascular tissue responsible for transporting organic compounds, such as sugars.

Lignin

A polymer that strengthens water-conducting cells, allowing for vertical growth in vascular plants.