Angiosperms

The most diverse group of plants, with about 14,000 genera and 257,000 species.

Angiosperms

How do angiosperms differ from gymnosperms?

Angiosperms

How do angiosperms differ from gymnosperms?

1)The ovules of angiosperms are borne inside

carpels, instead of on scales as in gymnosperms.

Angiosperms

How do angiosperms differ from gymnosperms?

1)The ovules of angiosperms are borne inside

carpels, instead of on scales as in gymnosperms.

2) Angiosperms have flowers instead of the cones

of gymnosperms.

Angiosperms

How do angiosperms differ from gymnosperms?

1)The ovules of angiosperms are borne inside

carpels, instead of on scales as in gymnosperms.

2) Angiosperms have flowers instead of the cones

of gymnosperms.

3) A unique part of the life cycle of angiosperms is

double-fertilization.

Angiosperms

How do angiosperms differ from gymnosperms?

3) A unique part of the life cycle of angiosperms is

double-fertilization.

In double-fertilization, the two sperm nuclei in the

pollen tube each participate in a fertilization

event.

4) Another key feature in angiosperms is the rapid

reproductive cycle.

Another key feature in angiosperms is the rapid

reproductive cycle.

Many gymnosperms are slow growing and have lengthy reproductive cycles. Angiosperms can have very rapid reproduction, including the herbaceous growth form and annual plants.

Major Angiosperm Clades

Major Angiosperm Clades

-The relationships of major angiosperm groups are modeled

after the Angiosperm Phylogeny Group 2009 system

(APGIII 2009).

APG III 2009

-uses molecular and morphological data

APG III 2009

-uses molecular and morphological data

-recognizes only those angiosperm families that are

monophyletic

-classifies one to several families into orders where there is

strong evidence that the order is monophyletic

APG III 2009

Orders can be viewed as convenient placeholders for 1 or

more families that appear to comprise a monophyletic group.

APG III 2009

Some monophyletic groups that contain several orders are

given names.

Ex: Magnoliids

Major Angiosperm Clades

Basal Angiosperms

Major Angiosperm Clades

Basal angiosperm groups:

Amborella

Water lilies

Star anise and relatives

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Many phylogenetic analyses agree in placing Amborella

trichopoda (Amborellaceae) as sister to all of the flowering

plants.

This means that Amborella trichopoda is a descendent of the

oldest confirmed branch in the flowering plant family tree.

Amborellaceae

Amborella trichopoda is a small, evergreen, shrub

of New Caledonia.

Amborellaceae

Amborella trichopoda is a small,

evergreen, shrub of New

Caledonia.

Amborellaceae

It only occurs in the moist, shaded understory of tropical

mountainside forests.

Major Angiosperm Clades

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Nymphaeaceae

Nymphaeaceae (water lilies)

and Cabombaceae (water

shields) are successive sister

groups to all other angiosperms.

Nymphaeaceae

Aquatic herbaceous plants.

Grow from rhizomes.

The water lilies represent the form of basal

angiosperms.

Radially symmetrical

flowers with tepals

(undifferentiated petals

and sepals).

Nymphaeaceae-Arkansas flora

Nuphar advena [syn. N. lutea]

Nymphaeaceae-Arkansas flora

Nuphar advena [syn. N. lutea]

Nymphaeaceae-Arkansas flora

Nymphaea odorata subsp. odorata [syn. N. odorata]

http://www.ct-botanical-society.org/galleries/pics_n/nymphaeaodor.jpg

Monocot Eudicot

The old group dicot included all the angiosperms

other than Monocots.

Dicot

Dicot

Recent molecular studies do not support the simple

division of angiosperms into dicots and monocots.

Basal Angiosperms

Dicot is no longer used to designate an angiosperm

lineage because it is not monophyletic

Dicot

Dicot

Dicot is no longer used to designate an angiosperm

lineage because it is not monophyletic

The core angiosperms comprise three lineages:

1.Magnoliids

2.Monocots

3.Eudicots

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The Magnoliids

Mostly tropical, subtropical,

and warm temperate.

The Magnoliids

Mostly tropical, subtropical,

and warm temperate.

Magnolia has spirally

arranged tepals, stamens

and carpels.

The Magnoliids

Mostly tropical, subtropical,

and warm temperate.

The seeds are

borne on an

almost cone-like

structure

The Magnoliids

For many years, the simple

Magnolia flower was

thought to represent the

primitive angiosperm

flower

The Magnoliids include many commercially

important plants including

Nutmeg

Myristica fragrans

http://www.amsar.com/p11.htm

The Magnoliids include many commercially

important plants including

Avocado

Persea americana

http://en.wikipedia.org/wiki/Avocado

The Magnoliids include many commercially

important plants including

Black pepper

Piper nigrum

http://plants.usda.gov/java/profile?symbol=PINI3

Magnoliids common in Arkansas include:

Southern Magnolia

Magnolia grandiflora

http://en.wikipedia.org/wiki/Southern_magnolia

Magnoliids common in Arkansas include:

Pawpaw

Asimina triloba

http://en.wikipedia.org/wiki/Pawpaw

Magnoliids common in Arkansas include:

Sassafras

Sassafras albidum

http://en.wikipedia.org/wiki/Sassafras

The Monocots

Monocots are distinguished from other angiosperms by the presence of a single cotyledon (seed leaf).

The Monocots

Major monocot groups are the lilies, palms,

grasses, sedges and bromeliads

Note the flower parts in

threes and the leaves with

parallel venation, all

typical of monocots.

Monocots in the human diet

The Eudicots

The Eudicots

The eudicots are separated from all other angiosperms

by a special pollen form.

The Eudicots

The eudicots are separated from all other

angiosperms by a special pollen form.

Eudicot pollen has three apertures.

Tricolpate pollen

Monocot Eudicot

Basal Angiosperms

The eudicots include three major lineages.

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Core eudicot food plants, with rosids (green branch) and asterids (red branch) collapsed.

http://botanistinthekitchen.wordpress.com

Foods in the asterids

http://botanistinthekitchen.wordpress.com

Rosid major clades with food species

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http://botanistinthekitchen.wordpress.com

Food in the fabids

http://botanistinthekitchen.wordpress.com

Food in the malvids

http://botanistinthekitchen.wordpress.com

Flowers

The parts of the flower are

arranged in successive

whorls above the

receptacle.

The first whorl is

composed of sepals.

The sepals are

collectively referred to as

the calyx.

The second whorl is made

up of petals.

The petals are collectively

referred to as the corolla.

The petals and sepals

together are called the

perianth.

The next whorl of the

flower is the androecium,

comprised of stamens.

The next whorl of the

flower is the androecium,

comprised of stamens.

The stamens have 2

parts, the slender filament

and the anther, which

rests on top of the

filament.

The androecium is the

male portion of the flower,

where the pollen is

produced.

The final whorl is the

gynoecium, the female

part of the flower.

The final whorl is the

gynoecium, the female

part of the flower.

The gynoecium comprises

one or more carpels.

The final whorl is the

gynoecium, the female

part of the flower.

The gynoecium comprises

one or more carpels.

The pistil can either be a

single carpel or multiple

carpels fused together.

At the base of the pistil is

the ovary, where the egg

cells are formed and

fertilization occurs.

An elongate style elevates

the stigma above the

ovary.

At the base of the pistil is

the ovary, where the egg

cells are formed and

fertilization occurs.

An elongate style elevates

the stigma above the

ovary.

The stigma is where

pollen lands, which is the

first step toward

fertilization of the egg.

The Androecium: structures of the anther.

The anther generally has four pollen sacs.

Each pollen sac produces a number of microsporocytes.

Each microsprocyte undergoes meiosis to produce

four haploid microspores.

The nucleus of each microspore then divides without

cytokinesis to form the pollen grain with 2 nuclei.

The pollen grain wall has a pattern that varies widely

among different types of angiosperms.

All angiosperm pollen grain walls are tough and

contain the hard material, sporopollenin.

Iris pollen

Ambrosia pollen

(ragweed)

When the pollen grains are mature, the anther walls

break open and the pollen is released.

Through the process of pollination, the pollen is

transported to the stigma of the same or a different

flower.

The pollen grain germinates, producing a pollen tube

that grows down through the style of the pistil.

The Gynoecium: structures of the carpel.

The simplest gynoecium is a pistil comprised of a

single folded carpel, also called a simple pistil.

More often, there are several separate carpels or

fused carpels.

A group of fused carpels is called a compound

pistil.

The ovary has one to several chambers called

locules.

Inside the locules, the ovules are attached to the

ovary by special tissue called placenta (plural

placentae).