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What is 1 + 3?
modifications for successful life on land
1. reduction of gametophyte size
2. the almighty seed
importance of pollen
no longer needed water for fertilization
importance of seeds
-zygotes developed into sporophyte embryos with packaged food supply in a protective coating.
-replaces spores as means of dispersal
points of gametophytes being reduced
seed plants are even more reduced
reverses trend gametophyte/sporophyte relationship.
diploid generation can withstand solar radiation with extra chromosomes
coated resilient polymer
where are pollen grains produced?
developed from microspores from microsporangia.
What is the development of seed associated with?
______ became the vehicle for sperm cells in plants
megasporangium of seed plants, fleshy structure. Unlike a chamber of spores like ancestors.
tissues surrounds the megasporangium, part of protective coating.
resulting structure consisting of megaspore, megasporagnium, and integuments
female gametophyte develops within the wall of the ______ and is nourished by the _________
egg from gametophyte is fertilized, the zygote becomes a _____________
sporophyte containing ovule develops into a ______
some ___________ have flagellated sperms, e.g. (________)
Gymnosperms are _______ than Angiosperms
gymnosperms lack __________
enclosed chamber (ovary) in which seed develop
Florida native cycad
Florida coontie, Zamila Pumila
Groups of Gymnosperms
cycads, ginkgo, gnetophytes, conifers
largest group of gymnosperms
needle shape conifer leaves are adapted for __________
characteristics adapted for dry conditions
thick cuticle on leafs
stomata are in pits, less water loss
needles are megaphylls, i.e. leaves
from ephedra, gnentophyte
Male gametophyte of pine is in the _____________
pollen grain, there is no antheridium
Female gametophyte of pine is in the ___________
ovule, consists of nutritive tissue and archengonium.
Conifers are _________, male and female gametophyte develop from different types of spores produced by different _________.
pollen cones have ___________, under goes meiosis producing __________ microspores.
microspores developed into pollen grains, i.e.
the male gametophyte
megaspores becomes female gametophyte, consists of _________ and ________
egg and endosperm mother cell
Ovulate has Megasporangia, each megasporangium (nucellus) is enclosed in a protective integuments wiht a single opening called __________
male cones and female cones, respectively
pollen cone and ovulate cone
It takes ____ years to complete pine life cycle
pollen falls onto the ovulate and is drawn into the ovule through the ___________
Pollen grain germinates in the ovule, forming ________, that begins to digest its way through the nucellus.
male gametophytes in seed plants are ________
endosperm is haploid or diploid?
haploid, only the egg is fertilized to be diploid.
megaspore mother cell produces 4 megaspore, only which one will survive, giving rise to
the female gametophyte
fertilization occurs more than one year after pollination,
two sperm cells developed from pollen tube and pollen tube grown through nucellus to reach female gametophyte
more than one egg can be fertilized, but...
only one zygote developes into embryo
new pine embryo, _____________
new sporophyte, gets embedded in the female gametophyte, nourishes until capable of photosythesis, it is now a ________
seed; with (2n) embryo, food source (n) endosperm), seed coat 2n integuments of parent's.
scales of the cone releases winged seeds carried by the wind, this replaces the _________ as a means of dispersal.
evolutionary significance of petal, nectar and fragrance?
reproductive structure of angiosperm, compressed shoot with four whorls of modified leaves
enclose the bud
you know what petals are idiot
anther and filament, produces pollen
evolved from seed beareing leaf, that became rolled into a tube. Made up of stigma, ovule, style.
protect ovules, which later become seeds. No archegonium in ovule.
angiosperms disperse seeds through
fruits, ripoened ovary that protect dormant seeds and disperses
several ovaries that are part of the same flower,eg raspberries
one that develope from several separate flowers, eg pineapple
modifications of fruits that aid in dispersal
shapes like kites for wind dispersal.
burr-like fruit cling to animal fur
edible fruit passes through digestive tract, dispersing miles away
The female gametophyte of angiosperms do not produce __________, located within an
angiosperm gametophyte has embryo sac with
eight haploid nuclei, but seven cells. One cell is (n+n) not 2n, this is the future endosperm.
double fertilization happens when
two sperm fertilize the (n+n) to form make (3n)endosperm and an egg, to make an embryo (2n)
angiosperm embryo develop with rudimentary roots and one or two seed leaves called,
cotyledons, ex. dicotyledons and monocotyledons.
seed coat is derived from
integuments, outer layers of ovules.
ovule becomes seeds, ovaries becomes
fruits,ovules are inside ovaries.