Transcript Introduction

Introduction
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Monocots: A monocot is a plant that
produces one seed leaf, as opposed
to a dicot which is a plant that
produces two leaf seeds. A plant
that is a monocot may be a
flowering plant, or may include some
food plants as well.
Other names for monocots:
- monocotyledons
- liliopsida
Monocotyledons & dicotyledons are
the two main groups of flowering
plants.
One-quarter of all flowering plants
species are made up by monocots.
Economically monocots are perhaps
the most important organisms on
earth.
Corn, rice, wheat and barley are our
four more important food and they
all come from monocots.
Introduction (cont…)
Monocots evolved
100-120 million years
ago
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Many tropical fruits such
as bananas, pineapple,
coconuts and dates come
from monocots.
•Numerous vegetation
types are dominated by
monocots including:
palm savannas, cattail
marshes and
grassland.
Characteristics of
Monocot Flowers
Flowers
· The petals, stamens, and other flower parts of monocots
are usually found in threes or multiples of three.
Leaf
· The leaf veins in monocots typically run parallel to the
length of the leaf.
Pollen
· In monocots, the pollen spores feature a single furrow or
pore through the monosulcate, or outer layer.
Stem
· The vascular structure of monocots is grouped in long
strands of vascular bundles. These bundles form a
cylinder and appear as small dots when the stem is cut.
The vascular bundles are scattered throughout the stem,
often appearing more towards the edges than the middle.
Roots
· Instead of sprouting from the bottom of the seed, roots in
monocots develop from nodes in the stem. When the roots
are grouped near the bottom of the stem, they're known as
prop roots.
Types of Monocot Flowers
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Grasses
The grasses comprise one of the largest
groups. Also called poaceaes, there are
over 9,000 species in this family of plants.
Although we may not typically think of
grasses as flowers, these plants actually
have small flowers at the tips. A number
of plants that we may not actually realize
are grasses also belong to this group,
including corn, wheat and rice.
Types of Monocot
Flowers
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Orchids
Orchids and other members of the
orchidaceae family are also
monocots, with the 20,000 to
25,000 species making up about
30 percent of all monocots.
Orchids are distinctive because of
their stamens and pistils, which
are responsible for reproduction
for the flower. Like most
monocots, they have petals in
groups of three. The pollen of
orchids is usually found in
masses called pollinia, and one of
the petals on the flower usually
forms a "lip" to make the flower
symmetrical.
Types of Monocot Flowers
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Asparagales
There are around 5,000 species
that are part of the asparagales
family, all of which are types of
monocots. This family of flowering
plants includes aloe, onion,
asparagus, garlic, daffodils and
daylilies. Most of these plants
have a cluster of leaves at either
the base or tip of their truck, and
their seeds are coated with
phytomelanin, which is a sooty
black substance
Types of Monocot Flowers
True Lilies
The lilales familiy, also called "true lilies," is a group
of flowers with about 1,200 species. Many flowers
that we call lilies, including water lilies and arum
lilies, are actually not a part of this group. Instead,
members of this group include tulips, bomareas (a
type of tropical vine), wake robins and mariposa
lilies. All members of the true lily family grow from
bulbs or corms, which keep the flower alive during
the winter.
Structure
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Monocots are plants whose seeds
have one cotyledon, a food-storing
structure. Seeds of dicots have two
cotyledons.
In addition to the number of
cotyledons per seed, monocots and
dicots differ in other ways. In
monocots, vascular bundles, groups
of conductive tissue, are scattered
throughout the stem, but in dicots,
they are arranged in an outer circle.
Monocots have long, narrow leaves
with parallel veins. Dicot leaves are
broad with branched veins. Flower
parts of monocots are arranged in
threes or multiples of three, but flower
parts of dicots are arranged in fours
or fives or mulitples of four or five.
Common monocots include plants of
great value to humans, such as
bananas, and cereals such as corn,
wheat, rice, and barley. Ornamental
flowers that are monocots include
tulips, orchids, and lilies. Beans,
carrots, peas, and potatoes are dicots.
The number of species of dicots is
much greater than number of species
of monocots.
Facts
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monocots  Sexual Reproduction
There are approximately 50,000 species of
monocots
Monocots tend to grow quickly and their
stems stay soft and pliable, except for
bamboos and palms. Most are herbaceous.
The flower parts of monocots, such as petals,
tend to be set in threes or multiples of three
Question # 1
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T/F monocots are plants whose
seeds have two cotyledon.
Answer # 1
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False
Question # 2
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What are the other two names for
monocots?
Answer # 2
- monocotyledons
- liliopsida
Question # 3
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Floral parts of monocots are often
in multiples of ________ .
Answer # 3
vocabulary
Flower - In an angiosperm, a short stem with up to four sets of modified leaves, bearing
structures that function in sexual reproduction.
Carpel - The ovule–producing reproductive organ of a flower, consisting of the stigma,
style, and ovary.
Style - The stalk of a flower’s carpel, with the ovary at the base and the stigma at the
top.
Fruit - A mature ovary of a flower that protects dormant seeds and aids in their
dispersal.
Embryo sac - The female gametophyte of angiosperms, formed from the growth and
division of the megaspore into a multicellular structure with eight haploid nuclei.
Endosperm - A nutrient–rich tissue formed by the union of a sperm cell with two polar
nuclei during double fertilization, which provides nourishment to the developing
embryo in angiosperm seeds.
Monocots - A clade consisting of flowering plants that have one embryonic seed leaf, or
cotyledon.
Dicots - A term traditionally used to refer to flowering plants that have two embryonic
seed leaves, or cotyledons. Recent molecular evidence indicates that dicots do not form
a clade (see eudicots).