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TAKSONOMI TUMBUHAN BERPEMBULUH

Drs. Endang Dayat, M.Si.Drs. Didi Jaya Santri, M.Si.

Pendahuluan

Manusia dan Hewan sehari-hari bergantung hidupnya pada beranekaragam tumbuhan

Sejak 20.000 th y.l., manusia purba sudah mengenali tumbuhan lokal sebagai bahan makanan, obat-obatan dan peralatan, dan potensi lainnya seperti racun.

Untuk itu kita perlu mengenal keragaman tumbuhan mengenal Untuk itu kita perlu mengenal keragaman tumbuhan, mengenal gambaran struktural yang signifikan (karakter kunci) dan mengidentifikasi berbagai jenisnya (species)

Karena itu bidang Sistematik Tumbuhan mempunyai akar budaya yang mendalam di berbagai belahan dunia.

Sistem klasifikasi angiospermae yang berkembang sekarang dikembangkan dari Eropa, tidak berarti bahwa tidak ada peran budaya African, Asian, and Native American dalam botani modern (see the Plant Trivia Timeline).

Sistematik Tumbuhan mencakup keanekaragaman, identifikasi, penamaan, klasifikasi dan evolusi tumbuhan.

Taksonomi tumbuhan: prinsip, prosedur dan peraturandasar klasifikasi tumbuhan; bagian dari sistematik tumbuhan

Tujuan taksonomi tumbuhan Inventarisasi flora Memberikan metoda untuk identifikasi dan komunikasie be a eto a u tu e t as a o u as Menghasilkan sistem klasifikasi terpadu dan universal Menunjukkan implikasi evolusi dari keanekaragaman

tumbuhan Memberikan nama ilmiah tunggal dalam bahasa latin

Pendekatan dalam taksonomi Taksonomi tradisional (alfa taksonomi) Taksonomi modern / biosistematik (omega taksonomi) Taksonomi numerik

Fenetik Kladistik

Taksonomi kimia

Dasar-Dasar Taksonomi: Klasifikasi: Pengelompokan organisme dalam sistem menurut

kategori tertentu. Satuan dasar klasifikasi: jenis (species). Setiapkesatuan taksonomi disebut takson

Identifikasi: Pemberian nama suatu organisme denganmenggunakan pustaka (kuncideterminasi, flora), gambar, spesimen herbarium, tumbuhan hidup yang telah diketahuinamanya kartu berlubang komputer dan lain-lainnamanya, kartu berlubang, komputer dan lain-lain.

Nomenklatur: sistem pemberian nama atau tatanamatumbuhan secara ilmiah (KITT), yakni dengan sistem binomial (Carolus Linnaeus)

Latin Indonesia Contoh Akhiran

Regnum Vegetabile Dunia Tumbuhan

Divisio Divisi Magnoliophyta -phyta

Subdivisio Anak Divisi

Classis Kelas Magnoliopsida -opsida

Tingkatan Takson

Subclassis Anak Kelas Asteridae -idae

Ordo Bangsa Asterales -ales

Subordo Anak Bangsa -inae

Familia Suku Asteraceae -aceae

Sub Familia Anak Suku

Genus Marga Vernonia

Subgenus Anak Marga

Spesies Jenis V. angustifolia Michx.

Subspecies Anak Jenis

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Nomenklatur Pemberian nama tumbuhan Penting untuk penelitian dan komunikasi ilmiah Perlu adanya keseragaman dalam pemberian nama tumbuhan Nama tumbuhan non ilmiah (lokal, daerah) vs ilmiah

Beberapa permasalahan nama non ilmiah Nama berbeda untuk tumbuhan yang sama Nama yang sama untuk tumbuhan berbeda Nama yang sama untuk tumbuhan berbeda

Tidak menunjukkan tingkatan taksa

Buttercup (elsewhere) Ranunculus sp.

Buttercup (East Texas) Oenothera speciosa

Sejarah Singkat TatanamaTumbuhan Pre Linnaeus Eupatorium cannabinum, foliis in caule ad genicula ternis, floribus parvis,

umbellatim in summis caulibus dispositis, Marilandicum polinomialnomenclature

Carolus Linnaeus (1700 an) standarisasi sistem tata nama tumbuhan binomial nomenclature Species Plantarum (1753) Species Plantarum (1753)

Augustin Pyramus de Candole (awal 1800 an) Yang pertama kali membuat kode tata nama internasional

American vs European (akhir 1800 an hingga awal 1900 an) International Code of Botanical Nomenclature (ICBN) (1930) International Botanical Congres (4-6th)

Modifikasi kode Saint Louis Code (online) (1999) ICBN terbagi menjadi Aturan (Rule) dan Saran (Recommendation)

Prinsip-Prinsip ICBN

Nomenklatur satu gugus takson didasarkan atas prioritas publikasi Cannabis sativa L. 1753 C. indica Lam. 1785 C ruderalis janischevsky 1924 C. ruderalis janischevsky 1924Nama yang paling awal dipakai C. sativa.

Nama ilmiah gugus taksonomi diperlakukan sebagai nama latin dari manapun asalnya Shorea palembanica Melaleuca cajuputi

Prinsip-Prinsip ICBN

Setiap gugus taksonomi, dengan sirkumskripsi, posisi danrangking tertentu hanya dapat mempunyai satu nama yang betul, kecuali beberapa nama (Nomina conservanda) Palmae – Arecaceae Gramineae – Poaceae Cruciferae – Brassicaceae Leguminosae – Fabaceae Guttiferae – Clusiaceae Umbelliferae – Apiaceae Compositae – Asteraceae

Binomial Nomenclature

Epitheton specificumGenus ( )

Author

Morus alba L.

Epitheton specificum (Petunjuk Jenis)

(Marga) (Linnaeus)

Ditulis miring (italic) ataudigaris bawahi

Nama ilmiah dan Author

Solanum torvum L. Shorea javanica Kooders et Valeton Raphanus sativus L. var. radicula Pers. Taxodium distichum (L.) Rich. Pithecelobium fagifolium Blume ex Miquelf g f q Hibiscus x archeri Wats Oryza sativa L. forma glutinosa Auct. Oryza sativa “si gadis” Sinonim : Thuya aphylla L (1753) &

Tamarix articulataVahl. (1791)Homonim : Viburnum fragrans Loisel (1824) dan

Viburnum fragrans Bunge (1831)Azas Prioritas

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An overview of land plant evolution

Bryophytes(nonvascular plants) Seedless vascular plants Seed plants

Vascular plants

Land plants

Origin of seed plants( b t 360 )

Ch

arop

hyc

ean

s

Liv

erw

orts

Hor

nw

orts

Mos

ses

sses

, qu

illw

orts

)

e rset

ails

, wh

isk

fer

n)

Gym

nos

per

ms

An

gios

per

ms

Vascular plants began to evolve during the Carboniferous period

(about 360 mya)

Origin of vascular plants (about 420 mya)

Origin of land plants(about 475 mya)

Ancestralgreen alga

Lyc

oph

ytes

(clu

b m

osse

s, s

pik

e m

o s

Pte

rop

hyt

e(f

ern

s, h

or

Figure 29.7

The Phyla of Extant Plant

Table 29.1

Origins and Traits of Vascular Plants

Fossils of the forerunners of vascular plants Date back about 420 million years

• These early tiny plantsHad independent branching sporophytes

Figure 29.11

– Had independent, branching sporophytes– Lacked other derived traits of vascular

plants

Life Cycles with Dominant Sporophytes

In contrast with bryophytes Sporophytes of seedless vascular plants are

the larger generation, as in the familiar leafy fern

The gametophytes are tiny plants that grow on or below the soil surface

The life cycle of a fernSporangia release spores.

Most fern species produce a singletype of spore that gives rise to abisexual gametophyte.

1 The fern sporedevelops into a small,photosynthetic gametophyte.

2 Although this illustration shows an egg and sperm from the same gametophyte, a variety of mechanismspromote cross-fertilizationbetween gametophytes.

3

MEIOSIS

Sporangium

Haploid (n)Diploid (2n)

Spore Younggametophyte

Antheridium

Key

Fern sperm use flagellato swim from the antheridia to eggs in the archegonia.

4On the underside

of the sporophyte‘sreproductive leavesare spots called sori.Each sorus is acluster of sporangia.

6

A zygote develops into a newsporophyte, and the young plantgrows out from an archegoniumof its parent, the gametophyte.

5

Sporangium

Maturesporophyte

Newsporophyte

Zygote

FERTILIZATION

Archegonium

Egg

Fiddlehead

Sperm

Gametophyte

Sorus

Figure 29.12

Transport in Xylem and Phloem

Vascular plants have two types of vascular tissue Xylem and phloem

• Xylem– Conducts most of the water and minerals– Includes dead cells called tracheids

• Phloem– Distributes sugars, amino acids, and other organic

products– Consists of living cells

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Evolution of Roots

Roots Are organs that anchor vascular plants Enable vascular plants to absorb water and

nutrients from the soil May have evolved from subterranean stems

Evolution of Leaves Leaves

Are organs that increase the surface area of vascular plants, thereby capturing more solar energy for photosynthesis

• Leaves are categorized by two types– Microphylls, leaves with a single vein– Megaphylls, leaves with a highly branched vascular system

• According to one model of evolution– Microphylls evolved first, as outgrowths of stems

Vascular tissue

Microphylls, such as those of lycophytes, may have originated as small stem outgrowths supported by single, unbranched strands of vascular tissue.

(a) Megaphylls, which have branched vascular systems, may have evolved by the fusion of branched stems.

(b)

Figure 29.13a, b

Sporophylls and Spore Variations

Sporophylls Are modified leaves with sporangia

Most seedless vascular plants Are homosporous, producing one type of spore

that develops into a bisexual gametophyte

• All seed plants and some seedless vascular plants– Are heterosporous, having two types of

spores that give rise to male and female gametophytes

Classification of Seedless Vascular Plants

Seedless vascular plants form two phyla Lycophyta, including club mosses, spike mosses,

and quillworts Pterophyta, including ferns, horsetails, and whisk

ferns and their relatives

The general groups of seedless vascular plants

LYCOPHYTES (PHYLUM LYCOPHYTA)

Isoetesgunnii,a quillwort

Selaginella apoda,a spike moss

Strobili(clusters ofsporophylls)

PTEROPHYTES (PHYLUM PTEROPHYTA)

WHISK FERNS AND RELATIVES HORSETAILS FERNS

Diphasiastrum tristachyum, a club moss

Psilotumnudum,a whiskfern

Equisetumarvense,fieldhorsetail

Vegetative stem

Strobilus onfertile stem

Athyrium filix-femina, lady fern

Figure 29.14

Phylum Lycophyta:

Club Mosses, Spike Mosses, and Quillworts Modern species of lycophytes Are relics from a far more eminent past Are small herbaceous plants

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Phylum Pterophyta:

Ferns, Horsetails, and Whisk Ferns and Relatives Ferns Are the most diverse seedless vascular plants

The Significance of Seedless Vascular Plants

The ancestors of modern lycophytes, horsetails, and ferns Grew to great heights during the Carboniferous, forming

the first forests

Figure 29.15

The growth of these early forests May have helped produce the major global

cooling that characterized the end of the cooling that characterized the end of the Carboniferous period

Decayed and eventually became coal

Seed Plants: Feeding the World

Seeds changed the course of plant evolution Enabling their bearers to become the dominant producers

in most terrestrial ecosystems

Figure 30.1

The reduced gametophytes of seed plants are protected in ovules and pollen grains

In addition to seeds, the following are common to all seed plants Reduced gametophytes Heterospory Ovules Pollen

Advantages of Reduced Gametophytes

The gametophytes of seed plants Develop within the walls of spores retained within tissues of the

parent sporophyte

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Gametophyte/sporophyte relationships

Sporophyte dependent on gametophyte (mosses and other bryophytes).

(a) Large sporophyte and small, independent gametophyte (ferns and other seedless

(b)

Gametophyte(n)

Gametophyte(n)

Sporophyte(2n)

Sporophyte(2n)

Figure 30.2a–c

vascular plants).Microscopic femalegametophytes (n) inovulate cones(dependent)

Sporophyte (2n),the flowering plant(independent)

Microscopic malegametophytes (n)inside these partsof flowers(dependent)

Microscopic malegametophytes (n)in pollen cones(dependent) Sporophyte (2n)

(independent)

Microscopic femalegametophytes (n)inside these partsof flowers(dependent)

Reduced gametophyte dependent on sporophyte (seed plants: gymnosperms and angiosperms).

(c)

Heterospory: The Rule Among Seed Plants

Seed plants evolved from plants that had megasporangia Which produce megaspores that give rise to female

gametophytes

Seed plants evolved from plants that had microsporangia Which produce microspores that give rise to male gametophytes Which produce microspores that give rise to male gametophytes

Ovules and Production of Eggs

An ovule consists of A megasporangium, megaspore, and protective integuments

Integument

Figure 30.3a

(a) Unfertilized ovule. In this sectional view through the ovule of a pine (a gymnosperm), a fleshy megasporangium is surrounded by a protective layer of tissue called an integument. (Angiosperms have two integuments.)

Spore wall

Megasporangium(2n)

Megaspore (n)

Pollen and Production of Sperm

Microspores develop into pollen grains Which contain the male gametophytes of plants

Pollination Is the transfer of pollen to the part of a seed plant containing the

ovulesovules

If a pollen grain germinates It gives rise to a pollen tube that discharges two sperm

into the female gametophyte within the ovuleFemalegametophyte (n)

Egg nucleus (n)

Figure 30.3b

(b) Fertilized ovule. A megaspore develops into a multicellular female gametophyte. The micropyle,the only opening through the integument, allowsentry of a pollen grain. The pollen grain contains amale gametophyte, which develops a pollen tubethat discharges sperm.

Spore wall

Male gametophyte(within germinatingpollen grain) (n)

Egg nucleus (n)

Dischargedsperm nucleus (n)

Pollen grain (n)Micropyle

Pollen, which can be dispersed by air or animals Eliminated the water requirement for fertilization

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The Evolutionary Advantage of Seeds

A seed Develops from the whole ovule Is a sporophyte embryo, along with its food supply, packaged in a

protective coat

Seed coat

Figure 30.3c

Gymnosperm seed. Fertilization initiatesthe transformation of the ovule into a seed,which consists of a sporophyte embryo, a food supply, and a protective seed coat derived from the integument.

(c)

Seed coat(derived fromIntegument)

Food supply(femalegametophytetissue) (n)

Embryo (2n)(new sporophyte)

Gymnospermae / Pinophyta

Gymnosperms bear “naked” seeds, typically on cones Among the gymnosperms are many well-known conifers Or cone-bearing trees, including pine, fir, and redwood

The gymnosperms include four plant phyla Cycadophyta Gingkophyta Gnetophyta Coniferophytap y

Exploring Gymnosperm Diversity

PHYLUM CYCADOPHYTA PHYLUM GINKGOPHYTA

Cycas revoluta

Figure 30.4

Gnetum

Ephedra

Ovulate cones

Welwitschia

PHYLUM GNETOPHYTA

Cycas revoluta

Exploring Gymnosperm Diversity

Douglas fir

Pacificyew

Common juniper

Wollemia pine

PHYLUM CYCADOPHYTA

Figure 30.4

yew

Bristlecone pine Sequoia

Gymnosperm Evolution Fossil evidence reveals that by the

late Devonian Some plants, called progymnosperms,

had begun to acquire some adaptations that characterize seed plants

Gymnosperms appear early in the fossil record And dominated the Mesozoic terrestrial

ecosystems

Living seed plants Can be divided into two groups:

gymnosperms and angiospermsFigure 30.5

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A Closer Look at the Life Cycle of a Pine

Key features of the gymnosperm life cycle include Dominance of the sporophyte generation, the pine tree The development of seeds from fertilized ovules The role of pollen in transferring sperm to ovules

Ovule

Megasporocyte (2n)

Integument

Longitudinalsection ofovulate cone

Ovulatecone

Pollencone

Maturesporophyte(2n)

Microsporocytes(2n)

Pollengrains (n)(containing malegametophytes)

MEIOSIS

Micropyle

Germinatingpollen grain

Megasporangium

MEIOSIS

Key

Diploid (2n)Haploid (n)

The life cycle of a pineIn most

conifer species,each tree hasboth ovulate

and pollencones.

1

A pollen grainenters throughthe micropyleand germinates,forming a pollentube that slowlydigeststhrough themegasporangium.

4

An ovulate cone scale has twoovules, each containing a mega-sporangium. Only one ovule is shown.

2

Figure 30.6

Longitudinalsection ofpollen cone

SporophyllMicrosporangium

Survivingmegaspore (n)

Germinatingpollen grain

ArchegoniumIntegumentEgg (n)

Femalegametophyte

Germinatingpollen grain (n)

Dischargedsperm nucleus (n)

Pollentube

Egg nucleus (n)FERTILIZATION

Seed coat(derived fromparentsporophyte) (2n)

Food reserves(gametophytetissue) (n)

Embryo(new sporophyte)(2n)

Seeds on surfaceof ovulate scale

SeedlingA pollen cone contains many microsporangia

held in sporophylls. Each microsporangium contains microsporocytes (microspore mothercells). These undergo meiosis, giving rise tohaploid microspores that develop into pollen grains.

3

While thepollen tubedevelops, themegasporocyte(megasporemother cell)undergoes meiosis,producing fourhaploid cells. Onesurvives as amegaspore.

5

The female gametophytedevelops within the megasporeand contains two or threearchegonia, each with an egg.

6

By the time the eggs are mature,two sperm cells have developed in thepollen tube, which extends to thefemale gametophyte. Fertilization occurswhen sperm and egg nuclei unite.

7

Fertilization usually occurs morethan a year after pollination. All eggs

may be fertilized, but usually only onezygote develops into an embryo. The

ovule becomes a seed, consisting of an embryo, food supply, and seed coat.

8

Angiospermae / Magnoliophyta

The reproductive adaptations of angiosperms include flowers and fruits

Angiosperms Are commonly known as flowering plants Are seed plants that produce the reproductive structures called

flowers and fruits Are the most widespread and diverse of all plants

The key adaptations in the evolution of angiosperms Are flowers and fruits

Flowers

The flower Is an angiosperm structure specialized for sexual reproduction

A flower is a specialized shoot with modified leaves Sepals, which enclose the flower

Petals, which are brightly colored and attract pollinators

S hi h d ll Stamens, which produce pollen

Carpels, which produce ovules Anther

Filament

Stigma

Style

Ovary

Carpel

Petal

ReceptacleOvule

Sepal

Stamen

Fruits Fruits Typically consist of a

mature ovary(b) Ruby grapefruit, a fleshy fruit

with a hard outer layer andsoft inner layer of pericarp

(a) Tomato, a fleshy fruit withsoft outer and inner layersof pericarp

Figure 30.8a–e

(c) Nectarine, a fleshyfruit with a soft outerlayer and hard innerlayer (pit) of pericarp

(e) Walnut, a dry fruit that remains closed at maturity

(d) Milkweed, a dry fruit thatsplits open at maturity

Can be carried by wind, water, or animals to new locations, enhancing seed dispersal

Wings enable maple fruits to be easily carried by the wind.

(a)

Figure 30.9a–c

Seeds within berries and other edible fruits are often dispersed in animal feces.

(b)

The barbs of cockleburs facilitate seed dispersal by allowing the fruits to “hitchhike” on animals.

(c)

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The Angiosperm Life Cycle In the angiosperm life cycle Double fertilization occurs when a pollen tube discharges two

sperm into the female gametophyte within an ovule One sperm fertilizes the egg, while the other combines with two

nuclei in the center cell of the female gametophyte and initiates development of food-storing endospermdevelopment of food storing endosperm

The endosperm Nourishes the developing embryo

The life cycle of an angiospermKey

Mature flower onsporophyte plant(2n)

Ovule withmegasporangium (2n)

Male gametophyte(in pollen grain)

Microspore (n) Generative cell

Tube cell

OvaryMEIOSIS

MEIOSIS

Pollen

Haploid (n)

Diploid (2n)

Anther Microsporangium

Microsporocytes (2n)

Germinating

Anthers contain microsporangia.Each microsporangium contains micro-sporocytes (microspore mother cells) thatdivide by meiosis, producing microspores.

1Microspores form

pollen grains (containingmale gametophytes). Thegenerative cell will divideto form two sperm. Thetube cell will produce thepollen tube.

2

When a seedgerminates, the

embryo developsinto a mature

sporophyte.

7

Figure 30.10

Female gametophyte(embryo sac)

Nucleus ofdevelopingendosperm

(3n)

Dischargedsperm nuclei (n)

Pollentube

Pollentube

Sperm

Survivingmegaspore(n)

Stigma

Megasporangium(n)

grains

EggNucleus (n)

Zygote (2n)

Antipodal cellsPolar nucleiSynergidsEgg (n)

Embryo (2n)

Endosperm(foodSupply) (3n)

Seed coat (2n)

Seed

FERTILIZATION

Sperm(n)

Pollentube

Style

GerminatingSeed

In the megasporangiumof each ovule, themegasporocyte divides bymeiosis and produces fourmegaspores. The survivingmegaspore in each ovuleforms a female gametophyte(embryo sac).

3

After pollina-tion, eventuallytwo sperm nucleiare discharged ineach ovule.

4

Double fertilization occurs. One spermfertilizes the egg, forming a zygote. Theother sperm combines with the two polarnuclei to form the nucleus of the endosperm,which is triploid in this example.

5

The zygotedevelops into an

embryo that ispackaged alongwith food into aseed. (The fruit

tissues surround-ing the seed are

not shown).

6

Angiosperm Evolution

Clarifying the origin and diversification of angiosperms Poses fascinating challenges to evolutionary biologists

Angiosperms originated at least 140 million years ago And during the late Mesozoic, the major branches of the clade

diverged from their common ancestorg

Fossil Angiosperms Primitive fossils of 125-million-year-old angiosperms Display both derived and primitive traits

Carpel

Stamen

Figure 30.11a, b

Archaefructus sinensis, a 125-million-year-old fossil.

(a)

Artist’s reconstruction of Archaefructus sinensis

(b)

5 cm

An “Evo-Devo” Hypothesis of Flower Origins

In hypothesizing how pollen-producing and ovule-producing structures were combined into a single flower Scientist Michael Frohlich proposed that the ancestor of

angiosperms had separate pollen-producing and ovule-producing structuresstructures

Angiosperm Diversity

The two main groups of angiosperms Are monocots (Monocotyledonae/Liliopsida) and eudicots

(Dicotyledonae/Magnoliopsida)

Basal angiosperms Are less derived and include the flowering plants belonging to the

oldest lineagesoldest lineages

Magnoliids Share some traits with basal angiosperms but are more closely

related to monocots and eudicots

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Exploring Angiosperm Diversity

Amborella trichopoda Water lily (Nymphaea “Rene Gerard”)

Star anise (Illicium floridanum)

BASAL ANGIOSPERMS

HYPOTHETICAL TREE OF FLOWERING PLANTS

Figure 30.12

HYPOTHETICAL TREE OF FLOWERING PLANTS

MAGNOLIIDS

Am

bore

lla

Wat

er li

lies

Sta

r an

ise

and

rel

ativ

es

Mag

nol

iids

Mon

ocot

s

Eu

dic

ots

Southern magnolia (Magnoliagrandiflora)

Exploring Angiosperm Diversity

Orchid(Lemboglossumfossii)

MonocotCharacteristics

Embryos

Leafvenation

Veins usuallyparallel

One cotyledon Two cotyledons

Veins usuallynetlike

Californiapoppy(Eschscholziacalifornica)

Pyrenean oak(Quercuspyrenaica)

EudicotCharacteristics

MONOCOTS EUDICOTS

Figure 30.12

Stems

Roots

Pollen

Flowers

Pollen grain withone opening

Root systemUsually fibrous(no main root)

Vascular tissuescattered

Vascular tissueusually arranged

in ring

Taproot (main root)usually present

Pollen grain withthree openings

Zucchini(CucurbitaPepo), female(left) andmale flowers

Pea (Lathyrus nervosus,Lord Anson’sblue pea), a legume

Dog rose (Rosa canina), a wild rose

Pygmy date palm (Phoenix roebelenii)

Lily (Lilium“Enchant-ment”)

Barley (Hordeum vulgare),a grass

Anther

Stigma Floral organsusually in

multiples of three

Floral organs usuallyin multiples of

four or fiveFilament Ovary

Evolutionary Links Between Angiosperms and Animals

Pollination of flowers by animals and transport of seeds by animals Are two important relationships in terrestrial ecosystems

Figure 30.13a–c

(a) A flower pollinated by honeybees.This honeybee is harvesting pollen and nectar (a sugary solution secreted by flower glands) from a Scottish broom flower. The flower has a tripping mechanism that arches the stamens over the beeand dusts it with pollen, some ofwhich will rub off onto the stigmaof the next flower the bee visits.

(c) A flower pollinated by nocturnal animals. Some angiosperms, such as this cactus, depend mainly on nocturnal pollinators, including bats. Common adaptations of such plants include large, light-colored, highly fragrant flowers that nighttime pollinators can locate.

(b) A flower pollinated by hummingbirds.The long, thin beak and tongue of this rufous hummingbird enable the animal to probe flowers that secrete nectar deep within floral tubes. Before the hummer leaves, anthers will dust its beak and head feathers with pollen. Many flowers that are pollinated by birds are red or pink, colors to which bird eyes are especially sensitive.