Biol 108 Final part 2 Flashcards
Bryophytes
Informal name for mosses, liverworts and hornworts, live on land but lack vascular tissue
diverged earliest
form a paraphyletic group with the three phyla of non vascular plants
Characteristics of bryophytes
non vasular tissue
no true roots water absorbed through rhizoids
absence of true leaves and stoma
Life cycle of non vascular plants (bryophytes)
Gametophyte stage is dominant larger and longer living
(free living haploid stage)
Sporophytes remain physically attached to gametophyte and get nutrients from
Haploid spores are produced (1n), spores germinate into gametophyte which matures and a female or male each with gametangia Gametes are produced by meiosis and sperm and eggs come together through water
Sporophyte stage
the diploid gametophyte zygote develops under the nourishment of the female gametophyte and zygote develops into diploid embryo
the sporophyte is retained in the female gametophyte archegonium
sporophyte creates spores that are released from sproangium and through meiosis
Liverworts, hornworts and mosses
liverworts-no xylem or phloem, no stoma oil bodies
mosses-no xylem or phloem, stoma
hornworts- no xylem or phloem, single large chloroplast
Shared derived features of vascular plants
xylem, phloem, vascular tissue develop only on sporophyte
sporophyte is dominant stage
well developed true roots and leaves
Microphylls and megaphylls and sporophylls
micro-small leaves with single vein
mega-large leaves with highly branched vascular systems
sporophylls- modified with sporangia
sori-on the underside of leaf
strobili-cone like stuctures
Homosporous
plants have single type of spore that develops into bisexual gametophyte (MOST SEEDLESS VASCULAR)
Heterosporous-plants have megaspores (female gametophyte) and microspores (males gametophyte) (ALL SEED PLANTS)
Seedless vascular and bryophytes
With bryophytes-flagellated sperm use water
Life cycle of seedless vascular plants
Haploid spores are released (1n)
spores germinate into gametophyte
which mature into male and female gametophyte (archegonium and antheridium) which create a diploid zygote. sporophyte develops in archegonium and the gametophyte eventually dies off sporophyte becomes independent
Shared derived features of seed plansts
gametophyte develops in spore wall and retained by parent sporophyte
heterospory- all plants are heterosporous
ovules
pollen
seeds-fertilized ovule embryo nutrient supply and seed coat
Ovules
composed of megasporngium (2n) and Megaspore (1n) with one or more protective integuments
Gymnosperms have 1 integument
Angiosperms have 2 integuments
Pollen
microspores develop into male gametophytes within pollen grains outer layer of sporopollen is produced by sporophyte contains one gametophyte one generative tube-nuclei and one and one tube cell-pollen tube
Gymnosperms
naked seed plants vascular
seeds are exposed on sporophylls strobili
Gymnosperm phylums
Cycadophyta- male and female cones ferns, dioecious, flagellated sperm
Ginkophyta- fan shaped leaves
gnetophyta- xylem contains vessel elements
conferophyta- cones rely on wind to pollinate xylem lacks vessel elements
Angiosperms
seed coat vascular plants
three fs fruit, flower, double fertilization
