Angiosperms
Angiosperms
- Angiosperms are the most advanced tracheophytes
(vascular plants).
- Angiosperms are the flowering plants.
- Possess flowers, covered seeds & fruit.
- Angiosperms are unique in that ovules are born in carpels.
- Ovary tissue surrounds ovule (Covered Seed).
- Only group to have double fertilization
Egg + Sperm  Zygote and Polar Nuclei + Sperm  Endosperm Nucleus
- 2 Main groups Monocots and Dicots
(Magnoliids & Eudicots make up the dicots)
- One Division  Magnoliophyta (a.k.a Anthophyta).
Division Magnoliophyta (Anthophyta) – Flowering Plants
Class Magnoliopsida – Dicots
Class Liliopsida – Monocots
A Cladogram of the
Flowering Plants.
Division
Magnoliophyta
A phylogeny for the seed plants, showing the relationships between
angiosperms (6 groups on the right) and gymnosperms (4 groups on
the left) and their main lineages.
As you can see from this
diagram, the majority of
angiosperms have vessels
present (found in xylem).
Generalized
Life History of
an
Angiosperm
Angiosperm Diversity
Basal Angiosperms- about 170
species, they are ancestral to
monocots and dicots; includes
water lilies, star anise and
Amborella.
The water lily (Nymphaea odorata)
Angiosperm Diversity
Magnoliids – Some individuals have
lost vessels. Examples of
magnoliids: Southern flowering
magnolia, Tulip Tree, Sassafras.
Southern Flowering Magnolia
Angiosperm Diversity
Monocots – Single cotyledon, parallel
veins in leaves, flower parts in
threes, scattered vascular bundles
in stems, mostly no secondary
growth, often adventitious root
system.
Commelinid Clade (Nonshowy clade)
Monocot examples: Orchids,
grasses, lilies, palm, tulip, onion
Arrowhead, a monocot
Simplified cladogram of monocot orders, on the basis of DNA analysis.
The commelinid clade is nonshowy.
Angiosperm Diversity
Eudicots – Pollen with 3 apertures
(tricolpate pollen); net veined
leaves, two cotyledons, flower
parts in fours or fives, vascular
bundles in ring of stem, secondary
growth present in many species,
and often tap root system.
Eudicot examples: Composites
(Asters), Roses, Potato, Beans,
Melon, Oak, Hickory.
Simplified cladogram of
eudicots, based on several
data sets: ribosomal
nuclear genes, chloroplast
photosynthetic genes,
morphology and others.
Rosid clade is very diverse.
Asterids are usually
herbaceous and Asteracease
has the most species (12,000)
of any flowering plant family.
The gourd family (Cucurbitaceae), another member of the rosid
group.
Cotton, a
member of the
rosid group.
Monocots Versus Dicots
BIO 141 Botany with Laboratory
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