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Angiosperms - Flowering PlantsAngiosperms - Flowering Plants

Angiosperms focus of the courseAngiosperms focus of the course vast majority of plant diversityvast majority of plant diversity

systematics of other plants examined latersystematics of other plants examined later

What are the non-angiosperm land plants?What are the non-angiosperm land plants?

Arthur CronquistArthur Cronquists phyla (= divisions)s phyla (= divisions)

outdated!outdated!

most phyla are now called into questionmost phyla are now called into question

See first pages of Chpts 1 & 3 for moreSee first pages of Chpts 1 & 3 for more

detail (detail (Plant SystematicsPlant Systematics))

Fungi?Fungi?

Fungi collectively are not a natural groupFungi collectively are not a natural group More closely related to animals than to plantsMore closely related to animals than to plants

Charales - stonewortsCharales - stoneworts

Green algal lineageGreen algal lineage

Closest relatives to land plants?Closest relatives to land plants?

Bryophyta - bryophytesBryophyta - bryophytes

earliest land plants - non vascularearliest land plants - non vascular

gametophyte dominant, 16000 speciesgametophyte dominant, 16000 species

3 lineages3 lineages are they a natural group?are they a natural group?

hornwortshornworts mossesmosses mossesmosses

liverwortsliverworts liverwortsliverworts

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Lycopodiophyta - club mossesLycopodiophyta - club mosses

3 families, 1150 species3 families, 1150 species

sporophyte dominant, vascular, free sporingsporophyte dominant, vascular, free sporing are they sister to all other tracheophytes?are they sister to all other tracheophytes?

IsoetesIsoetes - quillworts- quillworts SelaginellaSelaginella - spike mosses- spike mosses

LycopodiumLycopodium --

club mossesclub mosses

Psilophyta - whisk fernsPsilophyta - whisk ferns

6 species in 2 genera6 species in 2 genera

vascular plants, leafless green stemmed,vascular plants, leafless green stemmed,lateral sporangialateral sporangia

are they primitive vascular plants? or reducedare they primitive vascular plants? or reduced

ferns?ferns?

PsilotumPsilotum habithabit PsilotumPsilotum branchbranch PsilotumPsilotum sporangiasporangia

Equisetophyta - horsetailsEquisetophyta - horsetails

15 species in15 species inEquisetumEquisetum

vascular plants, reduced leaves, terminalvascular plants, reduced leaves, terminal

sporangiasporangia

what are they related to?what are they related to?

Polypodiophyta - fernsPolypodiophyta - ferns

11000 species11000 species

immense variation in habit and habitatimmense variation in habit and habitat

spores produced in specialized sporangiaspores produced in specialized sporangia

need a lot of systematic work - tropics!need a lot of systematic work - tropics!

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Pinophyta - gymnospermsPinophyta - gymnosperms

conifersconifers


seed plants but seeds nakedseed plants but seeds naked often divided into 4 phylaoften divided into 4 phyla

is one closer to angiosperms?is one closer to angiosperms?

juniperjuniperfraser firfraser firpinepine

cycadscycads



seed plants but seeds nakedseed plants but seeds naked often divided into 4 phylaoften divided into 4 phyla


female strobilifemale strobilimale strobilusmale strobilus

ginkgoginkgo



seed plants but seeds nakedseed plants but seeds naked

often divided into 4 phylaoften divided into 4 phyla


ovulesovules male strobilimale strobili

mature seedsmature seeds

gnetophytesgnetophytes



seed plants but seeds nakedseed plants but seeds naked

often divided into 4 phylaoften divided into 4 phyla


Welwitschia mirabilisWelwitschia mirabilis

EphedraEphedra GnetumGnetum

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275,000 + species275,000 + species

seed plants with seeds encased inseed plants with seeds encased in

ovaryovary

flowers aflowers a key innovationkey innovation

Magnoliophyta - angiospermsMagnoliophyta - angiosperms Angiosperms - Flowering PlantsAngiosperms - Flowering Plants tremendous adaptive radiation ontremendous adaptive radiation on

land (and back into water)land (and back into water)

Angiosperms - Flowering PlantsAngiosperms - Flowering Plants tremendous adaptive radiation ontremendous adaptive radiation on


Eucalyptus regnansEucalyptus regnans

(Myrtaceae) over 100m tall and(Myrtaceae) over 100m tall and

19m dbh19m dbh

Eucalyptus regnansEucalyptus regnans

(Myrtaceae) -Tasmania(Myrtaceae) -Tasmania



Wolffia microscopicaWolffia microscopica

(Araceae) less than 1mm long(Araceae) less than 1mm long

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land (and back into water)land (and back into water)Rafflesia arnoldiiRafflesia arnoldii (Rafflesiaceae)(Rafflesiaceae)

from New Guinea, up to 1m acrossfrom New Guinea, up to 1m across

and 20lbsand 20lbs


land (and back into water)land (and back into water) largest inflorescencelargest inflorescence

Amorphophallus titanumAmorphophallus titanum (Araceae)(Araceae)

Who is this famous DutchWho is this famous Dutch

biologist from the early 20thbiologist from the early 20th

century who is standing next to thecentury who is standing next to the

titan arum? . . . and what is hetitan arum? . . . and what is he

famous for?famous for?

largest inflorescencelargest inflorescence

Amorphophallus titanumAmorphophallus titanum (Araceae)(Araceae)

Angiosperms - Flowering PlantsAngiosperms - Flowering Plants Angiosperms - Flowering PlantsAngiosperms - Flowering Plants tremendous adaptive radiation ontremendous adaptive radiation on


largest numbers of flowerslargest numbers of flowers

CoryphaCorypha palmpalm

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Magnoliophyta classificationMagnoliophyta classification

typically divided into twotypically divided into two

classesclasses dicotsdicots andand monocotsmonocots

Angiosperms - Flowering PlantsAngiosperms - Flowering Plants

artificial!artificial!

we will usewe will use AngiospermAngiosperm

Phylogeny GroupPhylogeny Group ((APG IIAPG II))

classification system of 2003classification system of 2003

The FlowerThe Flower Why Important?Why Important?

1.1. unlike anything else in other plants & extremelyunlike anything else in other plants & extremely

variable & co-evolved with animalsvariable & co-evolved with animals

2.2. floral features used in describing and idfloral features used in describing and idinging

3.3. plant specimens (herbarium) must include flowers orplant specimens (herbarium) must include flowers or

derived featuresderived features

4.4. classification of angiosperms relies on flowersclassification of angiosperms relies on flowers

The Flower:The Flower: most significant feature of angiospermsmost significant feature of angiosperms

CalochortusCalochortus - fairy lanterns & mariposas (images: T. Givnish)- fairy lanterns & mariposas (images: T. Givnish)

The FlowerThe Flower What is it?What is it?

specialized shootspecialized shoot = stem += stem +

leaves (folia)leaves (folia)

shoot is highlyshoot is highly modifiedmodified andand

determinatedeterminate (ceased to grow)(ceased to grow)


from Schleiden 1855from Schleiden 1855

foliar theoryfoliar theory of flower - J.W.of flower - J.W.

von Goethe invon Goethe in Attempt to InterpretAttempt to Interpret

the Metamorphosis of Plantsthe Metamorphosis of Plants

(1790)(1790)

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developmental/evolutionary origin of thedevelopmental/evolutionary origin of the

flower still debatedflower still debated

2.2. PseudanthialPseudanthial theory -theory -

compound shoot or conecompound shoot or cone

anthersanthers

ovulesovules

1.1. EuanthialEuanthial theory - (foliartheory - (foliar

theory) - single shoottheory) - single shoot

thus, a flower is a specialized shoot that:thus, a flower is a specialized shoot that:

1.1. isis determinatedeterminate (vs. indeterminate)(vs. indeterminate)

2.2. has ahas a modified stemmodified stem with compressed internodeswith compressed internodes

3.3. possessespossesses modified leavesmodified leaves with various functions,with various functions,

these determined by gene arrays (e.g., ABC model)these determined by gene arrays (e.g., ABC model)

4.4. often clustered in anoften clustered in an inflorescenceinflorescence (larger branch)(larger branch)


The FlowerThe Flower

1.1. PedunclePeduncle: floral stalk, the stem: floral stalk, the stem

supporting the flower; sometimessupporting the flower; sometimes

referred to as thereferred to as the pedicelpedicel

read chpt 9 inread chpt 9 in Plant SystematicsPlant Systematics!!

1st half deals with1st half deals with

vegetative features - we willvegetative features - we will

cover in lab 2 next weekcover in lab 2 next week

2nd half deals with2nd half deals withflowers/fruits - lab 3flowers/fruits - lab 3

2.2. ReceptacleReceptacle: modified floral: modified floral

stem or axis from which arisestem or axis from which arise

the floral appendages orthe floral appendages or

modified leavesmodified leaves


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3.3. SepalSepal: the outer whorl of leaves,: the outer whorl of leaves,

green and protective; collectivelygreen and protective; collectively

called thecalled the calyxcalyx


4.4. PetalPetal: the second whorl of: the second whorl of

leaves, typically brightlyleaves, typically brightly

colored, attracting pollinators;colored, attracting pollinators;

collectively called thecollectively called the corollacorolla


5.5. PerianthPerianth: collective term for: collective term for

sepals and petalssepals and petals

TepalsTepals if both similarif both similar oror if onlyif only

one reduced set (sepals)one reduced set (sepals)


8.8. StamenStamen: the male structure of: the male structure of

flower comprisingflower comprising filamentfilament andand

antheranther

collectively, stamens are thecollectively, stamens are the

androeciumandroecium (=(= house ofhouse of

malesmales))

can be leaf-like in primitivecan be leaf-like in primitive

angiospermsangiosperms


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6.6. FilamentFilament: slender stalk of: slender stalk of

the stamen supporting thethe stamen supporting the

anther; permits exsertion ofanther; permits exsertion of

anther with pollen out ofanther with pollen out of

flowerflower


7.7. AntherAnther: fertile portion of: fertile portion of

stamen that dehisces to releasestamen that dehisces to release

pollen grainspollen grains; composed of; composed of

anther sacsanther sacs


NectariesNectaries often near base ofoften near base of

stamensstamens

produceproduce nectar rewardnectar reward forfor

visitors who will move pollenvisitors who will move pollen

((pollinatorspollinators))

e.g., grass-of-parnassus &e.g., grass-of-parnassus &

fritillaryfritillary


13.13. PistilPistil: flask-shaped, female: flask-shaped, female

structure comprising threestructure comprising three

main partsmain parts

often referred to asoften referred to as carpelcarpel(s)(s)

all pistils (1 or more) areall pistils (1 or more) are

referred to as thereferred to as the gynoeciumgynoecium

(=(= house of femaleshouse of females))


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9.9. OvaryOvary: basal portion of pistil: basal portion of pistil

that contains ovules; at maturitythat contains ovules; at maturity

becomesbecomes fruitfruit with seedswith seeds

10.10. OvulesOvules: fertile portions of: fertile portions of

pistil that contain a femalepistil that contain a female

gametophyte (embryo sac);gametophyte (embryo sac);

develop intodevelop into seedsseeds afterafter

fertilizationfertilization


11.11. StyleStyle: slender stalk of pistil: slender stalk of pistil

above ovary that the pollenabove ovary that the pollen

tubes must pass through totubes must pass through to

reach eggs in ovulesreach eggs in ovules

12.12. StigmaStigma: receptive portion: receptive portion

at top of style that receivesat top of style that receivesand recognizes pollenand recognizes pollen


Pollination biologyPollination biology Study of the pollen, its transfer, and movementStudy of the pollen, its transfer, and movementdown the styledown the style


PistilPistil vs.vs. carpelcarpel

How do you know?How do you know?

3 examples3 examples

Carpels not fusedCarpels not fused

1.1. MonocarpicMonocarpic

2.2. ApocarpicApocarpic

Carpels fusedCarpels fused

3.3. SyncarpicSyncarpic


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1 floral1 floral leafleaf in gynoeciumin gynoecium

This gynoecium isThis gynoecium is

monocarpicmonocarpic

(one carpel)(one carpel)

FoldedFolded leafleaf 1 carpel = 1 pistil1 carpel = 1 pistil

MonocarpicMonocarpicThe FlowerThe Flower


monocarpicmonocarpic

(one carpel)(one carpel)

1 carpel = 1 pistil1 carpel = 1 pistil


legumeslegumes

If 9If 9 leavesleaves in one flowerin one flower

eacheach separatelyseparately formsforms

carpels,carpels,

then the flower has 9then the flower has 9

carpels and 9 pistils,carpels and 9 pistils,

gynoecium isgynoecium is apocarpicapocarpic

(separate carpels)(separate carpels)

Caltha palustris -Caltha palustris - Marsh marigoldMarsh marigold

9 fruits (pistils) from 1 flower9 fruits (pistils) from 1 flowerGynoecium isGynoecium is apocarpicapocarpic with 9 carpels or 9 pistilswith 9 carpels or 9 pistils

ApocarpicApocarpic


3 floral3 floral leavesleaves inin

gynoeciumgynoecium fusefuse


syncarpicsyncarpicThis gynoecium isThis gynoecium is

syncarpicsyncarpic

SyncarpicSyncarpic


3 carpels = 1 pistil3 carpels = 1 pistil

3 styles3 styles

3 carpels = 1 pistil3 carpels = 1 pistil

1 style1 style

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Placentation typesPlacentation types- arrangement of ovules,- arrangement of ovules,

provides hints to the number of carpelsprovides hints to the number of carpels

MarginalMarginal- found in- found in

almost all monocarpic oralmost all monocarpic or

apocarpic pistilsapocarpic pistils

AxileAxile- found in some- found in some

syncarpic pistilssyncarpic pistils


ParietalParietal- found in- found in

some syncarpicsome syncarpic

pistilspistils






pistilspistils




Free-centralFree-central- found in- found in

a few syncarpic pistilsa few syncarpic pistils



pistilspistils




Free-centralFree-central- found in- found in

a few syncarpic pistilsa few syncarpic pistils

BasalBasal- found in- found in

some monocarpic,some monocarpic,

apocarpic, orapocarpic, or

syncarpic pistilssyncarpic pistils

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perianthperianth spiralledspiralled

Common in primitiveCommon in primitive

angiospermsangiosperms

perianthperianth 5-merous5-merous

Common in dicotsCommon in dicots

Numerical planNumerical plan- merosity, arrangement of perianth- merosity, arrangement of perianth

not necessarily stamens or carpelsnot necessarily stamens or carpels



Occasional in dicotsOccasional in dicots


Common in monocots & someCommon in monocots & some

primitive angiospermsprimitive angiosperms


Numerical planNumerical plan- merosity, arrangement of perianth- merosity, arrangement of perianth

not necessarily stamens or carpelsnot necessarily stamens or carpels

FlowersFlowers radiallyradially

symmetricalsymmetrical

FlowersFlowers actinomorphicactinomorphic

FlowersFlowers bilaterallybilaterally

symmetricalsymmetrical

FlowersFlowers zygomorphiczygomorphic

Symmetry planSymmetry plan- perianth arrangement important in- perianth arrangement important in

pollination biologypollination biology


ConnationConnation: fusion of floral: fusion of floral

parts from theparts from the same whorlsame whorl

Fusion of carpelsFusion of carpels Syncarpic pistilSyncarpic pistil

Fusion of stamensFusion of stamens Staminal tubeStaminal tube Fusion of petalsFusion of petals Corolla tubeCorolla tube


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AdnationAdnation: fusion of floral: fusion of floral

parts fromparts from different whorlsdifferent whorls


SimpleSimple adnationadnation

Stamens fused onto innerStamens fused onto inner

surface of fused (connation)surface of fused (connation)

petalspetals

ComplexComplex adnationadnation

Sepals, petals, and stamens fuseSepals, petals, and stamens fuse

to form ato form a hypanthiumhypanthium


parts fromparts from different whorlsdifferent whorls

No adnation!No adnation!

Connation (fusion of similarConnation (fusion of similar

parts) may or may not occurparts) may or may not occur


e.g.,e.g., DrimysDrimys & sandwort& sandwort

Adnation of calyx,Adnation of calyx,corolla, & stamenscorolla, & stamens

== hypanthiumhypanthium



parts fromparts from different whorlsdifferent whorlse.g., cherry & rosee.g., cherry & rose



parts fromparts from different whorlsdifferent whorlse.g., horse gentian & fuchsiae.g., horse gentian & fuchsia

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Oenothera biennisOenothera biennis

Evening primroseEvening primrose

OnagraceaeOnagraceae

4 sepals (4 sepals (CACAlyx)lyx)

4 petals (4 petals (COCOrolla)rolla)

8 stamens (8 stamens (AAndroecium)ndroecium)

4 carpels (4 carpels (GGynoecium)ynoecium)

Floral formulaFloral formula- shorthand notation- shorthand notation











Carpels fused = 1 pistilCarpels fused = 1 pistil











Ovary inferiorOvary inferior











Ovary inferiorOvary inferior

Hypanthium (+ hypanthium tube)Hypanthium (+ hypanthium tube)

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TheThe flowerflower what is it?what is it?

a flower is a specialized shoot that:a flower is a specialized shoot that:

1.1. isis determinatedeterminate (vs. indeterminate)(vs. indeterminate)

2.2. has ahas a modified stemmodified stem with compressed internodeswith compressed internodes

3.3. possessespossesses modified leavesmodified leaves with various functions,with various functions,

these determined by gene arrays (e.g., ABC model)these determined by gene arrays (e.g., ABC model)

4.4. often clustered in anoften clustered in an inflorescenceinflorescence (larger branch)(larger branch)

Angiosperms -Angiosperms -

Floral StructureFloral Structure

See second half of Chpt 9 for more detailSee second half of Chpt 9 for more detail

((Plant SystematicsPlant Systematics))

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02 Flowers