Angiosperms: The Flowering
Plants
Mrs. Mangat
Biology 11
Discuss after this video: Is the Venus
Fly trap a plant or animal?
• http://www.youtube.com/watch?v=_DZiTACpr
hE
http://www.youtube.com/watch?v=uJpgMDOZI
nA&feature=endscreen&NR=1
General Characteristics
• Produce flowers and
fruit to attract
pollinators
• Seeds are not naked but
enclosed by protective
fruit which is formed by
the flower
• Deciduous (drop their
leaves every year)
(a) Wings enable maple fruits
to be easily carried by the wind.
(b) Seeds within berries and other
edible fruits are often dispersed
in animal feces.
(c) The barbs of cockleburs
facilitate seed dispersal by
allowing the fruits to
“hitchhike” on animals.
Divided Into 2 Groups
• 1. Monocotyledons
• 2. Dicotyledons
A Cotyledon is a seed leaf found in the
protected seeds of angiosperms that stores food
for the young sporophyte and becomes the first
leaf to appear as the seed germinates
Monocot vs. Dicot
Characteristics of Monocots
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One cotyledon in the seed
Single seed leaf
Vascular bundles are scattered throughout the stem
Parallel veins on the leaves
Floral parts in threes or multiple of three.
Characteristics of Dicots
• 2 cotyledons in the seed
• 2 seed leaves
• Vascular bundles are arranged in a ring near the
outside of the stem
• Branching network of veins on the leaves
• Floral parts in 4 or 5 or multiples of 4 or 5
Both have same basic structure of nodes and
internodes.
petiole
blade
leaf
Monocot or Dicot?
Flowers-Basic Structure
• The flower is the defining reproductive
adaptation of angiosperms
• Flowers are made up of four types of
modified leaves sepals, petals, stamens,
and carpels.
• 1. SEPALS-small, green-leaf structures that
surround the carpel and stamen
• 2. PETALS-brightly colored and fragrant to
attract polinators to the flower
Four parts continued………….
• 3. STAMENS-are the male reproductive organs
that produce microspores. Consist of lon, slender
FILAMENT with an ANTHER at its tip that
produces pollen.
• 4. CARPEL/PISTIL-are female reproductive
organs that produce megaspores and are found in
the centre of the flower. Consist of a sticky
STIGMA for catching pollen attached to a long
STYLE that connects to the OVARY. Inside the
ovary are OVULES in which the EGG
(gametophyte) develops. The ovule becomes the
SEED and the ovary becomes a protective FRUIT.
Angiosperm Life Cycle
• Mature plant is the sporophyte.
• Some plants easily self-pollinate, but most have mechanisms to
ensure cross-pollination.
• Male gametophytes reach female gametophytes by producing a
pollen tube.
Haploid, Diploid, or Triploid?
Fertilization Summary
• http://www.sumanasinc.com/webcontent/animations/cont
ent/angiosperm.html
• http://bcs.whfreeman.com/thelifewire8e/content/cat_010/
2904002.html
• When pollen tube reaches female gametophyte, sperm
nuclei enter
• One sperm nucleus fuses with egg=zygote
• Other with 2 polar nuclei already present in embryo sac=3N
(form triploid ENDOSPERM)
• Called DOUBLE FERTILIZATION
• Endosperm provides food for embryo
Joke of the day
• What did the male stamen say to the female
pistil?
I like your style!!!
Ha ha!!!!!
Homework
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Chapter 25 Section Reviews:
Page 540 #1-4
Page 542 #1-4
Angiosperm worksheet