Seedless Plants Overview

These flashcards cover key terms and concepts relating to seedless plants, their structures, life cycles, and ecological significance.

Seedless Plants

Plants that reproduce without seeds, including mosses, ferns, and horsetails.

Sporophyte

The diploid, spore-producing phase in the alternation of generations.

Gametophyte

The haploid phase that produces gametes in the alternation of generations.

Haplontic

Dominant haploid stage in the life cycle of an organism.

Diplontic

Dominant diploid stage in the life cycle of an organism.

Alternation of Generations

A reproductive cycle in which organisms have both a haploid and diploid multicellular stage.

Sporangia

Structures in which spores are produced.

Homosporous

Plants that produce only one type of spore.

Heterosporous

Plants that produce two types of spores: microspores and megaspores.

Sporopollenin

A tough polymer that protects the spores from desiccation.

Antheridium

The male gametangium that produces flagellated sperm.

Archegonium

The female gametangium where the embryo develops.

Apical Meristem

A region of undifferentiated cells that promotes growth in plant shoots and roots.

Cuticle

A waxy covering on leaves and stems that prevents water loss.

Xylem

The vascular tissue responsible for water and nutrient transport in plants.

Phloem

The vascular tissue responsible for transporting sugars and other organic nutrients.

Stomata

Small openings on leaves that allow gas exchange.

Bryophytes

Non-vascular plants, including mosses, liverworts, and hornworts.

Liverworts

A division of bryophytes that lack specialized conducting tissues.

Hornworts

Bryophytes with a dominant gametophyte and unique cylindrical sporophytes.

Mosses

The most diverse non-vascular plants, found in varied habitats.

Vascular Plants

Plants with specialized tissue for conducting water and nutrients.

Erosion Control

The process by which plants help to prevent soil erosion.

Nitrogen Fixation

The conversion of atmospheric nitrogen into a form usable by plants, often aided by symbiotic relationships.

Flagellated Sperm

Sperm cells that move with the help of flagella, requiring water for fertilization.

Gemmae

Asexual reproductive structures in liverworts.

Plasmodesmata

Channels that allow the transfer of materials between plant cells.

Cuticle

A protective, waxy layer on the surface of leaves and stems.

Fiddleheads

The coiled young fronds of ferns.

Sori

Clusters of sporangia found on the undersides of fern fronds.

Strobili

Cone-like structures that contain sporangia in certain plants.

Rhizomes

Underground stems that anchor plants and store nutrients.

Vascular Bundle

A cluster of xylem and phloem tissues in vascular plants.

Sphagnum Moss

A type of moss used to produce peat, which is a source of fuel.

Pulvinus

A thickened part of a leaf petiole or stem that allows for movement.

Embryophyte

A common name for land plants in reference to their embryonic development.

Flavonoids

Plant pigments that absorb UV light and have protective functions.

Secondary Metabolites

Complex organic molecules produced by plants that can have ecological roles.

Symbiosis

A close relationship between two organisms that benefits at least one of them.

Carboniferous Period

A geological period when large seedless plants thrived and contributed to coal formation.

Tracheophytes

Vascular plants capable of supporting land life due to water and nutrient conduction.

Gemmae Cups

Structures on liverworts that hold gemmae for asexual reproduction.

Sporophyte Dominance

In most seedless vascular plants, the sporophyte stage is the most conspicuous.

Photosynthesis

The process by which plants convert light energy into chemical energy.

Ecological Indicators

Species, such as mosses, that signal environmental conditions or changes.

Rizomes

Underground stems that serve as storage and reproductive structures in certain plants.