Seed Plants II : Angiosperms (Concepts (Angiosperm carpels (Closed Carpels…
Seed Plants II : Angiosperms
most advanced group of plants
The edges of sporophyll primordia crowd against each other and grow shut.
develops into a fruit.
the second sperm cell of the pollen tube fuses with the polar nuclei of the megagametophyte, producing the endosperm nucleus.
their ancestors lacked vessels so they also lack vessels.
fusion of the carpels into one structure.
fusion of petals into one structure.
flowers that are bilaterally symmetrical.
Changing concepts about Early Angiosperms
Catkins of pecan ; the axis bears many flowers, all with stamens but not carpels.
A flower of Magnolia is considered the typical ranalean flower.
Classification of Flowering Plants
Monocots or eudicots
Monocots has only one cotyledons
Eudicots has two cotyledons
The early angiosperms diverged into several clades called basal angiosperms.
Flowers have numerous sepals, stamens with all parts arranged in spirals like the leaves of the rosette plants
Monocot flowers would be dervied from an ancestral flower like this by mutations that result in only three or six of each type of floral appendage.
the perinath members are called tepals.
most often found in swamps and marshes.
monocots are believed to have originated as semiaquatic plants that inhabited swapms and marshes.
leaf may have consist of a leaf base and petiole.
presence of spots or lines on the petals.
carpels fuse side by side starting at their bases.
the fuses side called septa
septal nectaries are the open area which secretes nectar.
produce water- soluble pigments called betalains
nucleus cells proliferate and form a nutritive tissue called perisperm.
have iridoid compounds