Kindbergia oreganaPhoto: Surrey W.L. Jacobs

Bryophytes

For Biology 2410Utah State University

Kindbergia oreganaPhoto: Surrey W.L. Jacobs

Three groups

mosses

Leafy liverwort

hornwort

Characteristics Chlorophyll a, Starch, Cellulose No lignin Usually no conductive tissue,

sometimes poorly developed tissue Gametophyte dominant, perennial Sporophyte parasitic on gametophyte NEED MOIST ENVIRONMENT, when

active

Structure: Gametophyte Gametophore – leafy

structure or thick, conspicuous part

Gametophore produces archegonia and antheridia – which produce gametes

Moss gametophore

Thalloseliverwort

LeafyLiverwort

Sex! Sperm swim from antheridia

into archegonia and fertilize egg

Sporophyte grows out of archegonium

Antheridia

Archegonia,with egg

Structure: Sporophyte Sporophyte produces

capsule In capsule: MEIOSIS,

produces spores Spores fall to ground

and germinate to form protonema, first stage of gametophyte generation

Liverwort

Hornwort

Moss

ProtonemaProtonema

Nutrition Autotrophic Gametophore most important for

energy capture [In mosses and hornworts some photosynthesis in

sporophyte] Absorb water and nutrients through

leaves/body and rhizoids Some conduction by capillary action

Distribution & Role Most abundant in humid, temperate or

tropical regions Intercept rains drops – prevent wash-outs Pioneers Soil protection 100 years to regenerate trees; 300 years

to regenerate bryophyte flora Shelter and food

Three groups

mosses

Leafy liverwort

hornwort

Mosses Most abundant

bryophytes Persistent

sporophyte Leaves 3-ranked Leaves not lobed,

mostly 1 cell thick Leaves often with

costa

Moss Sporophyte Persistent Seta + capsule Capsule has:

Sporangium Peristome teeth Operculum

Covered by calyptra Calyptra = Top of

archegonium

Hairy calyptras

teethPeristometeeth

Liverworts Two kinds

Leafy Well-defined

leaves Ill-defined leaves

Thallose Big, dichotomous

lobes Small, rosettes

Liverworts Leafy – 2 or 3 rows Leaves often lobed Leaves no costa Two layouts

Incubus – water catching

Succubus – roof style Underleaves … Sporophyte ephemeral Capsule splits