Kindbergia oregana Photo: Surrey W.L. Jacobs
Bryophytes For Biology 2410 Utah State University Kindbergia oregana Photo: 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 Thallose liverwort Leafy Liverwort
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 Protonema
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 teeth Peristome teeth
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