LAND PLANTS AND THEIR EVOLUTION Chapter 19 Characteristics of Plants  Multicellular autotrophs  Cell wall of cellulose  Food stored as starch  Evolved from green algae  Primarily terrestrial

PROBLEMS OF LIFE ON LAND PROBLEMSOLUTION Obtain water Roots and root hairs Transport water, food Xylemphloem Prevent dessication Cutin, drop leaves, stomates Gravity Cell walls, lignin, xylem Obtain CO2 Stomates ReproducePollen—sperm Protect Embryo Seeds, Fruit

Plant Kingdom Non VascularVascular Bryophytes Tracheophytes MossesLiverworts

BRYOPHYTES Mosses and Liverworts Mosses and Liverworts 1.No vascular tissue (xylem and phloem) 2.No true roots, stems, flowers or leaves 3.Tiny! 4.Water is required for fertilization 5.Gametophyte generation is dominant.

MOSS ANATOMY  Antheridium: Reproductive structure that makes sperm  Archegonium: Reproductive structure that makes eggs  Protonema: A filament that grows into a new plant

ALTERNATION OF GENERATIONS  GAMETOPHYTE: plant generation that produces gametes  SPOROPHYTE: Plant generation that produces spores

Plant Life Cycle ALTERNATION OF GENERATIONS 2Nn Diploidhaploid

MOSS LIFE CYCLE: Alternation of Generations

Antheridia and Archegonia

Figure 29.16x Moss life cycle

Figure A moss sporangium with a “spore-shaker” tip

MOSS PROTONEMA Haploid or diploid?

Figure 29.16x Moss life cycle

Figure Sphagnum, or peat moss: Peat bog in Oneida County, Wisconsin (top), closeup of Sphagnum (bottom left), Sphagnum "leaf" (bottom right)

Figure 29.19x A peat moss bog in Norway

Figure The life cycle of Polytrichum, a moss (Layer 1)

Figure The life cycle of Polytrichum, a moss (Layer 2)

Figure The life cycle of Polytrichum, a moss (Layer 3)

LIVERWORT THALLUS (LEAF-LIKE BODY)

GEMMAE CUPS: ASEXUAL REPRODUCTION

Female liverworts with archegonia  This is a female liverwort.

Male liverworts with antheridia  Gemmae cups

What Sex are these liverworts?