flowers and reproduction
asexual reproduction
sexual reproduction #
plant life cycle
flower structures
gametophytes
fertilization
embryo and seed development
fruit development
cross pollination
stamen and style maturation times
stigma and pollen incompatibility
monoecious and dioecious species
animal pollinated flowers
wind pollinated flowers
ovary position #
inflorescence and pollination
fruit types and seed dispersal
true fruits and accessory fruits
classification of fruit types
fragmentation
cacti- parts of plant are not secured well. parts fall off and begin to grow roots
plants break apart and root elsewhere
gametes
sperm(male)
eggs(female)
sperm+egg= zygote- diploid
sporophyte- diploid
contains spores- haploid
difference between spores and gamete- spore cannot fuse with gametes in a process call fertilization
spores undergo mitosis forming a gametophyte
mammalian gametes- microgametes (male) and megagametes(female)
microgametophytes from microspores and megagametophytes from megaspores
life cycle with sporophyte + gametophyte is an alternation of generation
gametophytes represent a heteromorphie generation
stalk- pedicel
receptacle- where other flower parts are attached
floral appendages
sepals
petals
stamens
carpels
modified leaves that surround/enclose other flower parts
complete- having all 4 appaendages
incomplete- not having all four
above sepals
all petals together- corolla
perianth= sepals+petals
above the petals
all of the stamens together- androecium
male part of the flower
2 parts- filament and anther
located at the highest level on the receptacle
stigma, style, ovary
inside ovary- placentae and ovules
microspores develop in microgametophytes
vegative and generative cell
after pollen lands on stigma, pollen germinates by producing a pollen tube
megagametophytes
multinucleic sac- embryo sac
7 cells
large central cell with 2 polar nuclei
3 antipodal nuclei
2 synergid nuclei
involves both fusion with gametes and nuclei
angiosperm fertilization
2nd sperm nuclei migrates to synergid undergoing karyogamny producing an endospern nuclei
double fertilization- sperm fuses with both egg and polar nuclei
suspensor pushes embryo deep into endosperm
seed coat
integuments
ovary matures into fruit
exocarp- skin or peel of fruit
mesocarp- middle
endocarp- innermost layer of fruit
pericarp- entire fruit wall
pollination of carpel by pollen from a different individual
self-pollination- pollination of carpel by the same fower
self fertilization is prevented if anthers and stigmas different times
self pollination is inhibited by compatibility barriers
critical proteins are deposited on outer surface of developing pollen grain
monoecy- staminate flowers located on the same plant as carpellate flowers
doecy- speces only produce staminate flowers and others that produce carpallate flowers
imperfect flowers- flowers that lack either or both essential organs
perfect flowers- flower has both essential organs
nonessential organs- sepals and petals, do not produce spores
bright colors, smells of flowers attract animal pollinators
probability of pollen being distributed to another flower is very high
coevolution- flower becoming adaptive for visitation
shape of flower is important
flowers producing 2 halves that are mirror images- actinomorphic/regular
bilaterally symmetrical flowers- zygomorphic
probability of pollen being distributed to another flower is slim
species: gasses, oaks, hickories
no selective advantage of flower shape
ovary and ovules must be protected from pollinators
long styles and stamen filaments are adaptions to protect ovule
inferior ovary
epigynous
superior ovary- ovary above other flower parts
half inferior ovary-partially burried
many flowers grouped together
2 basic arrangements
determinate
indeterminate
limited potential for growth
lower/outermost flowers open first
fruits only containing ovarian tissues and accessory fruit
simple fruit- develops from a single ovary or fused ovaries from one flower
apples (true fruit) develop from inferior ovaries
fruit produced in simple fruit
aggregate fruit-carpels of one gynoecium fuses during development
raspberries
multiple fruit- all fruits of an inflorescence fuse into one fruit
dry or fleshy
dehiscent fruits break open and release seeds
indehiscent fruits do not release seeds
this is an image of wind pollination
this is an image of an aggregate fruit
this is an image showing the flower structure
pollination is sexual reproduction
plants can either have 1 or both male and female sexual organs