Bryophytes and Early Land Plants - Vocabulary

Vocabulary flashcards covering key bryophyte terms, their structures, life cycle roles, and differences among mosses, liverworts, and hornworts.

Bryophytes

Non-vascular land plants (mosses, liverworts, hornworts) with a dominant gametophyte and a dependent sporophyte; require water for reproduction.

Mosses (Phylum Bryophyta)

Bryophyte group whose gametophyte is leafy and anchored by rhizoids; lacks true vascular tissue.

Liverworts (Phylum Hepatophyta)

Bryophytes with prominent gametophyte thallus; sporophyte poorly developed; pores (not true stomata) on the epidermis.

Hornworts (Phylum Anthocerophyta)

Bryophytes with flat gametophyte thallus and elongated sporophyte; stomata present on sporophyte; Nostoc symbiosis common.

Gametophyte

Haploid, photosynthetic generation that produces gametes in bryophytes.

Sporophyte

Diploid generation that develops from the zygote and is typically dependent on the gametophyte for nutrition.

Archegonia

Female gametangia that produce eggs in bryophytes.

Antheridia

Male gametangia that produce sperm in bryophytes.

Sperm

Male gametes; usually flagellate and swim to archegonia in bryophytes.

Egg cell

Female gamete produced in archegonia.

Zygote

Diploid fertilization product that grows into the sporophyte.

Seta

Stalk of the sporophyte elevating the capsule.

Capsule (sporangium)

Sporangium at the tip of the sporophyte where spores develop.

Sporangium

Structure containing spores; develops into the capsule in bryophytes.

Peristome teeth

Hygroscopic teeth at the capsule end that help release spores.

Operculum

Lid covering the peristome that dehisces when spores mature.

Hygroscopic

Responding to humidity; drives movements that aid spore release.

Elaters

Hygroscopic leaf- or filament-like tissues in sporangia that aid spore dispersal (especially in liverworts).

Pseudo-elaters

Elater-like structures lacking spiral thickening; function in hornwort spore release.

Gemmae

Asexual propagules produced in liverwort gemmae cups for clonal reproduction.

Gemmae cups

Cup-like structures on liverworts containing gemmae.

Thallus

Body plan of many liverworts and hornworts; flattened, unstructured tissue.

Leafy vs. thallose

Gametophyte growth forms in liverworts: leafy (branched) or thallose (flat/simple).

Adaxial

Upper (dorsal) surface of a thallus or leaf; rich in chlorenchyma for photosynthesis.

Chlorenchyma

Chloroplast-rich tissue on the adaxial side used for photosynthesis.

Abaxial

Lower (ventral) surface of a thallus or leaf; storage tissue with few or no chloroplasts.

Nostoc (cyanobacteria)

Cyanobacterial symbionts in hornworts; fix atmospheric N2 and provide nitrogen for the plant.

Columella

Central column of sterile cells inside a hornwort sporangium aiding spore production.

Pyrenoids

Chloroplast-associated bodies; hornworts have one chloroplast per cell with pyrenoids.

Archegoniophore

Umbrella-like stalk bearing archegonia in liverworts.

Antheridiophore

Stalk bearing antheridia in liverworts.

Archegonium

Female gametangium containing the egg cell.

Antheridium

Male gametangium producing sperm.

Meiosis

Cell division producing haploid spores from a diploid cell.

Hepatophyta

Phylum name for liverworts, a basal lineage of bryophytes.

Anthocerophyta

Phylum name for hornworts, with distinctive sporophyte traits.