i. bryophytes - mosses = many plants growing in a tight pack. no waxy cuticle and do not retain...

I. Bryophytes - mosses = many plants growing in a tight pack.

• No waxy cuticle and do not retain developing embryos w/i mother plant’s gametangium.

• Need water to reproduce; sperm are flagellated, must swim through water to reach eggs

• No vascular tissue to carry water(grow low to ground) and lack lignin

• Like damp, shady places

• Green spongy plant = gametophyte (male & female are separate plant shoots)(n)

• Taller brown shoot with a capsule, grows out of gametohyte = sporophyte (2n)

Alternation of Generations -

2 generations that take turns producing each other

• Gametophytes produce eggs and sperm; must unite to form a zygote, which forms new sporophytes.

• Sporophytes produce spores

• Spores can develop into a new organism without uniting, & have a tough coat to resist harsh environments.

• The new organism then produces gametophytes again.

• Gametophyte = larger more obvious plant in mosses

• Moss- Gametophyte (left) and Archegonium (female gametophyte) (right)

(Antheridium = male gametopyte.)

• Sporophyte generation (left) and Sporangia (right)

• Moss is cool! E.C. for bringing in moss with both generations. (In late spring.)

• II. Ferns - diverse with 12,000 species, most in tropics, many in temperate woodlands of U.S.

• Evolution of vascular tissue (xylem and phloem)

• Sperm are still flagellated-must swim through a film of water to fertilize eggs

• Are still seedless - have spores

• During Carboniferous Period, ferns in swamp forests converted to coal - (black sedimentary rock made up of fossilized plant material)

• Alternation of

Generations in ferns.

• Sporophytes are diploid and gametophytes are haploid

• Sporophyte is the dominant stage in ferns. (Gametophyte was dominant in mosses)

• Heart shaped gametophyte = prothallus