Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh Edition Solomon Berg Martin Chapter 26 The Plant Kingdom: Seedless Plants
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Environmental challenges of living on land required evolution of adaptations Anatomical Physiological Reproductive
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Examples of adaptations Cuticle to prevent water loss Stomata for photosynthesis Alternation of generations –Gametophyte –Sporophyte
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Basic plant life cycle
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Generalized reproductive structures of algae and plants
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Alternation of generations, cont. Gametophyte produces gametes by mitosis Gametes fuse to form zygote Zygote develops into embryo
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Alternation of generations, cont. Mature sporophyte develops from embryo, producing sporogenous cells Sporogenous cells undergo meiosis to form spores
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Examples of adaptations, cont. Gametangia protect gametes –Antheridia –Archegonia Xylem conducts water and sugar nutrients Phloem conducts dissolved sugar
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Plant gametangia
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Plants are probably descended from charophytes Both have similar biochemical characteristics –Same photosynthetic pigments –Same cell wall components –Same carbohydrate storage material –Similarities in fundamental processes
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Plant evolution
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Features distinguishing bryophytes from green algae and other plants Bryophytes have cuticle, stomata, etc. Bryophytes are non-vascular and do not have xylem or phloem Bryophytes have a dominant gametophyte generation
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants The three phyla of bryophytes Phylum Bryophyta (gametophytes grow from protonema) Phylum Hepaticophyta (some have gametophytes that are thalli) Phylum Anthocerotophyta (thalloid gametophytes)
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants The life cycle of mosses Green moss gametophyte bears archegonia and/or antheridia During fertilization, sperm cell fuses with egg cell in archegonium Zygote develops into embryo Embryo develops into moss sporophyte
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Life cycle of mosses
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants The life cycle of mosses, cont. Moss sporophyte is attached to gametophyte Meiosis occurs in capsule of sporophyte to produce spores When spore germinates, it germinates into a protonema that forms buds
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Life cycle of Marchantia polymorpha
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Features distinguishing ferns and other seedless vascular plants from algae and bryophytes Ferns and fern allies have adaptations including –Vascular tissues –A dominant sporophyte generation
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Evolution of microphylls and megaphylls
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants The four phyla of seedless vascular plants Phylum Polypodiophyta Phylum Psilotophyta Phlylum Equisetophyta Phylum Lycophyta
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants The life cycle of ferns Fern sporophytes have megaphylls Their fronds bear sporangia in clusters (sori) Meiosis in sporangia produces haploid spores Prothalli develop from these and bear both archegonia and antheridia
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Life cycle of ferns
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Generalized life cycles of homosporous and heterosporous plants Homospory –Bryophytes, whisk ferns, horsetails, most club mosses, and most ferns –Spores give rise to gametophyte plants producing both egg and sperm cells
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Generalized life cycles of homosporous and heterosporous plants, cont. Heterospory –Some clubmosses, some ferns, and all seed plants –Microspores give rise to male gametophytes –Megaspores give rise to female gametophytes
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Basic life cycle of heterosporous plants
Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 26 The Plant Kingdom: Seedless Plants Life cycle of Selaginella