Chapter 28: Seed plants
cotelydons
"seed leaf"; embryonic seed leaf
flower (angiosperms)
... may contain: - sepals - petals - stamens - carpels
sporophyte
A pine is a mature _____.
life cycle of angiosperms (1)
SPOROPHYTE GENERATION is dominant; gametophytes are: reduced in SIZE, nutritionally dependent on SPOROPHYTE generation
ovules, fruit
___ are enclosed within an ovary after fertilization, OVULES become SEEDS; OVARY develops into... (angiosperms, reproduction)
phylum pinophyta
conifers that produce: - wood - bark - needles - seeds in cones most are monoecious
phylum gnetophytes
consist of 3 genera - gnetum - ephedra - welwitschia (survives on fog) unique among gymnosperms, sharing traits with angiosperms: - vessel elements in their xylem - cone clusters resemble flower clusters - life cycle details resemble those of angiosperms
life cycle of angiosperms (2)
heterosporous; within flower, they produce MICROSPORES and MEGASPORES
phylum cycadophyta
look like palms or ferns diecious, but reproduce with pollen and seeds in conelike structures once numerous (during mesozoic era), now few members left
carpels
the "female" organ; produces gametes in floral plant
stamens
the "male" organ; produces gametes in floral plant
gymnosperms (distinguishing characteristics)
vascular plants with seeds - totally exposed or - on cones produce wind-borne pollen grains
sexually, fruits
(evolutionary adaptations of flowering plants) reproduce ____ by forming flowers; after double fertilization, seeds formed within ____
imperfect flower
If a plant is missing one or more characteristics of a flower (sepals, stamens, petals, carpels), then they are considered a(n)...
perfect flower
If all characteristics of a flower (sepals, stamens, petals, carpels) are within a plant, then they are considered a(n)...
microspores, air, megasporangium, pollen tube, archegonium, embryo
Male cones produce ____. [same as one before] develop into pollen grains. Pollen grains carried by ___ to female cones. One megaspore develops into a female gametophyte in a _____. After pollination, ____ ___ penetrates megasporangium. [same as before] reaches egg in the _____. After fertilization, zygote develops into ____. [life cycle of pine]
2
each pollen grain from microspores has _ sperm cells (life cycle of angiosperms)
life cycle of angiosperms (4)
egg cell and central cell with 2 polar nuclei participate in fertilization double fertilization resulting in formation of: - diploid zygote - triploid endosperm
8
embryo sac contains SEVEN cells with _ nuclei (life cycle of angiosperms)
seeds
embryonic development is further advanced contain an abundant food supply each has a protective ____ coat [(same as above) are reproductively superior to spores]
pollen grains
immature male gametophytes; life cycle of pine
life cycle of angiosperms (3)
microspores develop into pollen grain (EACH POLLEN HAS 2 SPERM CELLS); megaspores develop into an embryo sac; embryo sac contains 7 cells with 8 nuclei
pollen grain, embryo sac
microspores develop into... megaspores develop into... (life cycle of angiosperms)
core angiosperms
monocots, eudicots "dicots", and magnoliids
monocots
most have floral parts in multiples of 3; seeds that each contain one cotyledon; nutritive tissue in their mature seeds is endosperm ex) popcorn
eudicots (dicots)
most have floral parts in multiples of 4 or 5; seeds that each contain 2 cotyledons; nutritive organs in their mature seeds are the cotyledons
4 phyla of gymnosperms
phlyum pinophyta, phylum cycadophyta, phylum ginkgophyta, phylum gnetophyta
anthophyta
phylum ___ is divided into 2 clades: - basal angiosperms (primitive) - core angiosperms (advanced)
angiosperms
phylum anthopohyta/phylum magnoliophyta vascular plant that produces flowers and seeds enclosed within fruit the most diverse and successful group of plants
life cycle of pine
pine gametophytes are small and nutritionally dependent on sporophyte pine is HETEROSPOROUS and, in separate cones, produces: - microspores - megaspores male cones produce microspores; microspores develop into pollen grains; pollen grains carried by air to female cones; one megaspore develops into a female gametophyte in a megasporangium; after pollination, pollen tube penetrates megasporangium; pollen tube reaches egg in the archegonium; after fertilization, zygote develops into embryo
features of seeds
primary means of reproduction and dispersal for gymosperms and angiosperms; seeds are reproductively superior to spores
phylum ginkgophyta
sole member is Ginkgo biloba deciduous (shedding leaves annually) dioecious female ginkgo produces seeds directly on branches