LAND PLANTS AND THEIR EVOLUTION Chapter 19 Characteristics

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 PROBLEM SOLUTION Obtain water Transport water, food Roots and root hairs Xylem phloem Prevent dessication Gravity Obtain CO 2 Reproduce Protect Embryo Cutin, drop leaves, stomates Cell walls, lignin, xylem Stomates Pollen—sperm Seeds, Fruit

Plant Kingdom Non Vascular Bryophytes Mosses Liverworts Vascular Tracheophytes

BRYOPHYTES 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 2 N n Diploid haploid

MOSS LIFE CYCLE: Alternation of Generations

Antheridia and Archegonia

Figure 29. 16 x Moss life cycle

Figure 29. 16 x Moss life cycle

Figure 29. 18 A moss sporangium with a “spore-shaker” tip

MOSS PROTONEMA Haploid or diploid?

Figure 29. 16 x Moss life cycle

Figure 29. 19 Sphagnum, or peat moss: Peat bog in Oneida County, Wisconsin (top), closeup of Sphagnum (bottom left), Sphagnum "leaf" (bottom right)

Figure 29. 19 x A peat moss bog in Norway

Figure 29. 16 The life cycle of Polytrichum, a moss (Layer 1)

Figure 29. 16 The life cycle of Polytrichum, a moss (Layer 2)

Figure 29. 16 The life cycle of Polytrichum, a moss (Layer 3)

LIVERWORT THALLUS (LEAF-LIKE BODY)

GEMMAE CUPS: REPRODUCTION ASEXUAL

Female liverworts with archegonia § This is a female liverwort.

Male liverworts with antheridia § Gemmae cups

What Sex are these liverworts?