10/13 Gymnosperms Flashcards
Seedless plants have tiny gametophytes that are dependent on the…?
Sporophyte
Life cycle of a seed plant
Heterospory
Heterospory
Production of two different size of spores and sexes in the same plant.
microspores
smaller, male gametophyte
megaspores
larger, female gametophyte
Innovation
gametophytes develop from spores that are retain by the sporophyte
sperm
travels by pollen
seed plants
sporophyte is dominant
pollen grain
male gametophyte
sperm no longer needs
water
terrestrial adaptations of seed plants
female gametophyte develops inside the ovule
Ovule consists of
Megasporangium, megaspore and the protective tissue (integument)
Megaspore remain within the…
parent sporophyte
Megaspore develops into the..
female gametophyte (has one or more eggs)
adaptation
sporophyte tissue protects the megasporangium after fertilization.
seedless plants have…
vascular tissue in the sporophyte
megasporangium
produces spores
female gametophyte
in the ovule
ovule develop into seeds when?
after fertilization
fact
sperm fertilizes the egg –> zygote –> sporophyte embryo
ovule surrounding the embryo is what?
seed coat and food supply
seeds have 3 generations which are?
unfertilized ovule, fertilized ovule and gymnosperm seed
pollen grain release how many sperms in the microphyle?
2 sperms
gymnosperms bear naked seeds where?
typically on cones
gymnospores have tiny gametophytes where?
on its cones
second largest group of gymnosperms after conifers?
Phylum cycadophyta (cycads)
Phylum cycadophyta
have fern like features (pinnate leaves)
Phylum cycadophyta
have cones (non photosynthesizing reproductive structures)
Cycads thrived during what era?
dinosaur era (today restricted to tropical parts)
Cycads are dioecious
having the male and female reproductive organs in separate individuals.
(cycads) sperm is flagellated but confined where?
in the pollen tube
Phylum Cycadophyta (cycads).. Zamia pumila only native where?
only native in the US
Zamia pumila
are poisonous and a butterfly consumes it therefore making it poisonous too.
Phylum Ginkgophyta (Ginkgo)
ginkgo biloba is the only surviving species
Phylum Ginkgophyta (Ginkgo)
fan like leaves, turn gold in the fall.
Phylum Ginkgophyta (Ginkgo)
popular in cities because they can tolerate air pollution well.
Phylum Ginkgophyta (Ginkgo)
sperm are flagellated but confined to a pollen tube
seeds are fleshly
Phylum Coniferopyta (conifers)
largest group of gymnosperms
Phylum coniferopyta (conifers) group include
cypresses, pines, redwoods, firs and junipers
Phylum Coniferopyta (conifers) form forests where?
Northern Hemisphere
Evergreen
stay green throughout the year, have needle leafs, less surface area, less water and does not hold snow during winter, survive harsh conditions, start photosynthesis right away after winter is over.
Conifers
used to make paper, pinenuts, wood for houses (rapid growth)
Phylum coniferopyta (conifers) SEQUOIAS
are the largest living things, can weigh 24 blue whales.
Phylum coniferopyta (conifers) REDWOOD
are the tallest living thing
Phylum Gnetophyta: Ephedra and Welwitschia
similarities with angiosperms, flower like strobili, loss of archegonia and double fertilization
Phylum Gnetophyta Welwitschia
live in SW Africa
Phylum Gnetophyta Ephedra
found in the US
(Seed plants) which generation is the dominant one?
sporophyte
(Seed plants) which generation disperses the species?
sporophyte
(Seed plants) what are the key differences between seedless vascular plants and the seed plants?
pollen, vascular tissue, larger surface area