introduction plantae (seedless) liverworts hornworts mosses nonvascular fern whisk fern horsetail...
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Plantae (Seedless)
Nonvascular
•Liverworts •Hornworts •Mosses
Vascular
•Fern •Whisk fern •Horsetail •Club mosses
1. Phylum Psilophyta (Whisk ferns)2. Phylum Lycopodophyta (Club
Mosses)3. Phylum Sphenophyta (Horsetails)4. Phylum Pterophyta (Ferns)
1 2 3 4
Alternation of generationsHaploid (n) stage that produces gametes
followed by diploid (2n) stage producing spores
Gametophyte (haploid) that produces gametes. Gametes fuse to form zygotes that develop into sporophytes
Sporophytes (diploid) that produce spores. Spores are haploid cells that can develop into a new organism without fusing with another cell.
Homosporous and Heterosporous
HomosporousOne spore type produced and released
HeterosporousTwo spore types produced one developing
into a male gametophyte, the other into a female gametophyte
Only one size of spore is produced The spore germinates into a bisexual
gametophyte. The gametophyte releases the sex cells,
or gametes,then fertilize and produce a zygote.
The zygote, over time, then develops into a sporophyte, the plant.
Two sizes of spores are produced. The spore germinates into a gametophyte. The gametophyte will then produce
megaspores(egg) and microspores(sperm). After receiving water, the sperm will swim out
of the microsprorangium and go inside the megasporangium, where it will fertilize the egg.
After many years, the sporophyte will grow out of the megasporangium or microsporangium
Dominant generationIn alternation of generations, the dominant
generation is the generation that occupies the largest portion of the life cycle.
Bryophytes
No vascular tissues Live in damp/moist environments and are
small Gametophyte is the dominant generation in
the life cycles of bryophytes Root
Absent Rhizoid (root like structure)
Gametophyte of a moss is dominanceLargest and longest lived generation
Green moss gametophyte produces gametangia Function : Produce gametes Male (antheridia-produce sperm)Female (archegonia-produce egg)
Gamete protect by jacket of sterile cell- protect from drying and dying
Male gamete/ spermSmallHave flagellaEnable to swim through water to reach the
egg Female gamete/ egg
LargeContain much cytoplasmCan’t move
Gametophytes cover with water
Sperm swim to the egg and egg release chemical
Fertilization produce diploid zygote (2n)
Matured sporophytes Foot for anchors it to gametophytesStalk grow up from foot Capsule
○ Slender stalk, at the top○ Contain sporogenous cell /spore mother cell○ Covered by calyptra
Matured sporophyte, spore mother cells undergoes meiosis to form haploid spores
Spores begin gametophyte generation
Spore maturecapsule openspore carry of by windgerminateprotonemabudgametophyte
Asexual Reproduction
Fragmentation Small pieces broken from gametophyte,
grow into new plant Gemmae
Tiny pieces of tissues from new gametophyte
When raindrop splash,gemmae germinate to gametophyte
Liverworts
Hepaticophyta Gametophyte dominated
generation Thallus
Lobes structure Rhizoid
Anchor to soil
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