seed plants 2: angiosperms
changing concepts about early angiosperms
classification of flowering plants
basal angiosperms
commenlinoid monocots
eudicots
basal eudicots
rosid clade
asterid clade
ranalean flower- magnolia type flower was thought to be relictual
such flower is generalized- has all parts and are arranged spirally
carpels occur in a superior position
easy to postulate evolution of alltypes of flowers from ranalean generalized ancestor
monocots have 3 stamens + 3 carpels- eudicots have 4 of each
angiosperms are monophyletic
originated in Jurassic period
classified as either monocots or eudicots
monocots
have 1 cotyledon on each embryo
leaves have parallel veins
vascular bundles distributed throughout the stem
leaves are elongate and strap
never have ordinary secondary growth/ wood
flowers of monocots are separated in groups/multiples of 3
eudicots
2 cotyledon and reticulates venation in leaves
vascular bundles occur in one ring in stem
can be woody
flower parts occur in sets of 5, sometimes in sets of 4, and rarely in sets of 3
angiosperms divereged into basal angiosperms
amborella and austrobaileyales resemble eudicots
water lillies #
vascular bundles are scattered like monocots
lack wood
uniaperturate
only have single germination spore
eudicots have 3 germination pores
basal angio sperms and monocots are uniapertuate
believed to have risen from angiosperms
tepals- perianth members
angiosperms gave rise to monocots
parallel venation of leaves
ancestors had broad leaves and lived as aquatic plants
marginal type of meristem evolved
orders
assimilates- aquatic herbs
liliales - lilies
asparagales
septa- carpals fuse side by side
carpals do not fuse completely together and open areas to secrete nectar - septal nectaries
dioscoreales - starchy crop
contain a unique type of epicuticular wax
orders
arecales - the palms
poales - grass family and cattails
zingiberales - house plants such as maranta , gingers
large trees with with reduced wind pollinated flowers
order
caryophyllales
cacti
contains water soluble pigments called betalains
nuclear cells form a nutritive tissue called perisperm
santalales
parasitic plants
mistletoe
2 large clades
fabids aka eurosids 1
malvids aka eurosids 2
contains pinnately compound leaves
sunflowers, periwikles, petunia, and morning glory
sister clade to rosids
easily distinguished from other angiosperms
they have sympetalous flowers ( petals fused together into a tube)
always have a few stamens not more than the number of petal lobes
stamens alternate with petals
many asterid have iridoid compounds
2 small orders
lamiids aka euasterids 1
campanulids aka euasterids 2
this is an image of a eudicot cross section
this is an example of a monocot
this is an image of a basal angiosperm
monocots have flowering parts