To disperse off-spring to new locations away from thier parents
What do seed plants always produce?
Seeds and fruit
Why do seed plants produce fruit?
To attract animals to eat the fruit containing the seeds so the seeds will be distributed
What did the first vascular plants lack?
What were the first forests composed of?
Vascular plants that did not produce seeds
Like non-vascualar plants, what do ferns and other seedless vascular plants have?
Swimming sperm that require a film of water for fertilization
When did forests of vascular plants lacking seeds thrive?
In the warm, humid climate of the late Paleozoic era
What are teh most abundant and familiar group of seedless vascular plants?
What stage are the lives of non-vascular plants dominated by?
teh gametophyte stage
What do fern gametophytes produce thier eggs and sperm in and where are these located?
Eggs in archegonia
Sperm in antheridia
Located on the lower surface of the plant
What do fern sporophytes consist of?
Roots, horizontal underground stems called rhizomes, and long, often highly divided leaves called fronds
Where do clusters of spore-producing sporangia form?
On the lower surgafes of fronds
Explain a ferns life cycle.
The clusters of sporangia found on the underside of fronds undergo mieosis to create haploid spores. The haploid spores drop off the leaves into the ground and form a gametophyte. On the gametophyte is the antheridium and archegonia. The antheridium undergoes mitosis to create sperm and the archegonia undergoes mitosis to create eggs. Sperm swim to eggs and fertilize them to create a zygote that grows into the sporophyte.