Haploid Gametophyte contains archegonium and antheridium (produces haploid eggs and sperm cells through mitosis). 
Starting with the gametophyte, draw the life cycle of a typical moss. Protonema are thread like filaments that will develop into gametophyte. If spores disperse and land in ideal area, spores germinate and a protonema grows Calyptra covers and protects the capsule. 
Capsule contains haploid spores that will be released under ideal conditions. Contains seta or stalk raises spores for dispersal (by wind or water). Gametophyte is photosynthetic and supplies water and nutrients to the sporophyte that grows out of it. Sporophyte cannot live independently… Grows out of the gametophyte Diploid zygote forms and eventually germinates and grows into diploid sporophyte. When water is present, fertilization can occur if sperm swims to egg Sperm require water to swim to egg in archegonium… involves dew or rain droplets. Antheridium- produces flagellated sperm cells. Structures protect gametes (egg and sperm) from drying out. Rhizoids are root-like structures that anchor the moss to the ground. Gametophyte (haploid) generation is the common green fuzzy moss. Sporophyte (diploid) generation grows out of the gametophyte, and is a skinny stalk with a capsule full of spores at the top. Don’t have true roots to transport water. Water can only diffuse short distances to cells. Water moves by osmosis from one cell to the next. Don’t have vascular tissue to transport water. Gametophyte generation is dominant (mainly exist as a haploid individual). Require water for fertilization (adapted for wet habitats) Do NOT have true leaves, stems and roots. include ferns, conifers, and flowering plants. possess water/nutrient transporting system (xylem-water and phloem-nutrients from photosynthesis). include mosses, liverworts, and hornworts Vascular. - Lack vascular tissue which transport H2O and nutrients. General Plant Life Cycle Sporophyte is the dominant generation in higher plants (diploid stage: 2n) Gametophyte is the dominant generation in lower plants (haploid stage: n) Plant Phylogeny Cone-bearing plants (Gymnosperms) Flowering plants (Angiosperms) Ferns & relatives (Seedless vascular plants) Flowers: seeds enclosed in fruit Mosses & relatives (“Bryophytes) Seeds Water-conducting (vascular) tissue Green algae ancestor Plant Kingdom Distribution Cone-bearing Plants 760 species Flowering Plants 235,000 species Ferns & relatives 11,000 species Mosses & relatives 15,600 species Question to think about: Why bother move onto land? Helps to disperse spores and the meeting of gametes. Provides nutrients and gas exchange by diffusion. 
Gives structural support (less affected by gravity).Transition onto Land Advantages of living in the water included…
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