1.
PLANT
KINGDOM
By: Dr. Pritima Gupta

2.
SYSTEM OF CLASSIFICATION
CLASSIFICATION
HISTORICAL
CLASSIFICATION
Started from period of
Aristotle & Theophrastus
ending up to de Candolle.
MODERN
CLASSIFICATION
Includes classification from
Bentham & Hooker to
systems proposed till date.
• The earliest systems of
classification used only gross
superficial morphological
characters such as habit, colour,
number and shape of leaves, etc.
• Also, the artificial systems gave
equal weightage to vegetative and
sexual characteristics which is
unfair.
• So against this, natural
classification systems developed,
which were based on natural
affinities among the organisms
and consider, not only the
external features, but also
internal features, like
ultrastructure, anatomy,
embryology and phytochemistry.
Such a classification for flowering
plants was given by George
Bentham and Joseph Dalton

3.
TYPES OF SYSTEM OF CLASSIFICATION
Artificial
Classification
Natural
Classification
Phylogenetic
Classification
Phenetic
Classification
• Plants are
classified as per
convenience using
early recognizable
characteristics.
• Used habit, colour,
no., morphology
etc.
• Linnaeus gave the
best AS in 1735.
• Included external &
external features like
ultra-structure,
anatomy,
embryology,
phytochemistry etc.
• Bernard, de Jussieu
& de Condolle gave
significant
contributions.
• George Bentham &
Joseph Dalton
Hooker gave the
most imp class.
• Based upon
evolutionary & genetic
affinities of the plants.
• These systems
appeared after
publication of “Origin
of Species” by Darwin
in 1859.
• Engler (1886),
Hutchinson (1926) –
Phylogenetic
• Takhtajan (1967) &
Cronquist (1968) –
Modern.
a) Numerical
taxonomy/
Phenetics
b) Cladistic
(phylogenetic)
taxonomy
c) Cytotaxonomy
d) Chemotaxonomy

4.
INTRODUCTION
I. CRYPTOGAMS – Flowerless or seedless plants.
They include – 1. Thallophyta
2. Bryophyta
3. Pteridophyta
a) THALLOPHYTA – Most primitive & simple of all
plants.
Plant body – either unicellular or multicellular
thallus.
b) BRYOPHYTES – Constitute liverworts and
mosses.
Found in moist, shady and cold places.
c) TRACHEOPHYTES – Vascular plants like
pteridophytes, spermatophytes or
Phanerogams are included.
II. PHANEROGAMS – Seeds bearing plants.
Includes gymnosperms and angiosperms.
Land plants are divided into
these three categories.

5.
ALGAE
• It is derived from the Greek word Phykos which
means 'alga' or 'sea weed'.
• Undifferentiated body.
 SIZE AND FORM - Varies.
• Microscopic – Chlamydomonas; Kelps – Attaining
height upto 60m.
• Small colonial forms – Volvox to largest –
Macrocystis having length of several 100ft.
• Filamentous –
Branched – Cladophora
Unbranched – Spirogyra, Zygnema, Ulothrix.
Free floating
Attached with substratum.
• Multinucleate thallus without multiple cells –
Vaucheria.
• Specialised thalli cells bear – Lamina (leaf like
blade) and at times branches are attached t stem
like part – STIPE and attached with HOLDFAST.
HABITAT – Moist stones, soils and wood.
• Even in association with fungi (lichens) &
animals (Eg: Sloth bear).
• Zygnema, Oedogonium – Still water
• Batrachospermum – Red algae – Fresh water.
• Planeloid: Here the vegetative cells of the alga g
surrounded by a mucilaginous matrix e.g.,
Tetraspora.
• Dendroid: Here the colony appears like a
microscopic tree. There is secretion of mucilage
from the polar end e.g., Ecballocystis.

6.
Macrocystis
AlgaeonSloth
Cladophora
Kelps
Volvox
Spirogyra
Zygnema
Ulothrix
Vaucheria

7.
1. Surrounded by nutrients.
2. No need for vascular tissue.
3. Water keeps the algae buoyant.
4. Algae being flexible, tides and severe water
currents fail to affect them.
5. Water suitable medium for gametic fusion.
(a) CRYOPHYTES: Plants growing on snow or
ice are called as cryophytes.
(b) THERMOPHYTES: Plants growing in hot
water are called as thermophytes.
(c) EPIPHYTES: Several algal forms grow on
other plants (algae, angiosperms) as epiphytes.
#ADAPTATIONS FOR WATER
e.g., Oedogonium, Cladophora, Vaucheria
etc.
(d) ENDOPHYTES: Some blue-green algae
grows as endophytes inside other plants e.g.,
Anabaena growing inside the leaf of Azolla
(fern)
(e) EPIZOIC: Algae growing on the bodies of
animals are described as epizoic. e.g.,
Cladophora crispata grows on snail shell.
(f) ENDOZOIC: Algae growing inside the
body of animals. e.g., Chlorella grows with in
the tissue of Hydra.
(g) SYMBIOTIC FORMS: Some algae like
Chlorella, Nostoc etc. growing in symbiotic
relationship with members of Ascomycetes
and Basidiomycetes (Fungi) constitute the
lichen.
SPECIALIZED HABITATS

8.
REPRODUCTION IN
ALGAE
VEGETATIV
E
Fragmentation
and each
fragment
develops into a
thallus.
ASEXUA
L
SEXUAL
Isogamy : fusing gametes are
Same.
Anisogamy : fusing gametes
are different.
Chlamydomonas(some species)
Oogamy : fusing gametes
are totally different,
enough to be called as
male and female gametes.
Volvox, Fucus.
By the formation of
various types of nonmotile
or motile spores.
The most common being
the zoospores.
They are flagellated
(motile - Chlamydomonas)
and on
germination gives rise to
new plants.
In SR, the gametes could
be flagellated and similar
in size – Chlamydomonas
or non-flagellated (non-
motile) but similar in size
-Spirogyra.

9.
1. CHLOROPHYCEAE
2. PHAEOPHYCEAE
3. RHODOPHYCEAE
#CHLOROPHYCEAE – Pigments +nt in chloroplast which varies in shape
from discoid, plate-like, reticulate, cup shaped, spiral or ribbon shape. Most
of the members have one or more storage bodies called pyrenoids located in
the
Chloroplasts.
#PHAEOPHYCEAE – They are the ones which contains holdfast, stipe and
lamella. The gametes in this are pyriform.
#RHODOPHYCEAE – Found in well –lighted regions and even in water
depths.
TYPES OF ALGAE

10.
TYPES OF ALGAE
TYPE OF
ALGAE
MAJOR
PIGMENTS
STORED
FOOD
CELL WALL
MODE OF
REPRODUCTION
FLAGELLAR
NO. &
POSITION OF
INSERTIONS
HABITAT
COMPLEXITY
OF
STRUCTURE
MEMBERS
Chlorophyceae
(Green algae)
CHLOROPHYLL a,
b, beta – carotene &
other carotenoids
Starch Cellulose
Vegetative -
fragmentation or by
spores. Asexual -
flagellated zoospores.
Sexual -may be
isogamous, anisogamous
or oogamous
2-8, equal, apical
Fresh water,
brackish water,
salt water
Unicellular to
multicellular
(Colonial or
filamentous)
Chlamydomonas,
Volvox, Ulothrix,
Spirogyra and
Chara
Phaeophyceae
(Brown algae)
CHLOROPHYLL a,
c, fucoxanthin
Mannitol,
laminarin
Cellulose & algin
Vegetative –
Fragmentation. Asexual –
Biflagellate zoospore.
Sexual- may be
isogamous, anisogamous
or oogamous
2, unequal, lateral
Fresh water (rare)
brackish water,
salt water
Multicellular
(Simple branched,
filamentous)
Ectocarpus,
Dictyota,
Laminaria,
Sargassum and
Fucus
Rhodophyceae
(Red algae)
CHLOROPHYLL a,
b, r -phycoerythrin
Floridean
starch
Cellulose
Vegetative –
Fragmentation.
Asexual – non-motile
spores.
Sexual – Oogamous
Absent
Fresh water
(some) brackish
water, salt water
(most)
Unicellular to
multicellular
Polysiphonia,
Porphyra,
Gracilaria and
Gelidium.

11.
ECONOMIC
IMPORTANCE
OF ALGAE
POSITIVE
IMPORTANCE
1. Algae as food
2. As fodder
3. Algae in
industry
4. Algae in agriculture
5. Algae in sewage disposal
6. Algae in medicine
7. Algae in space research
8. Algae in natural fuel resource
NEGATIVE
IMPORTANCE
1. Toxicity
2.
Parasitism
3. Damage
4. Other effects
Linnaeus (1754) differentiated
a group of plant and called as
'algae' where he included
lichens and liverworts also.
Fritsch (1935) classified algae
into 11 classes as under:
(i) Chlorophyceae (Green algae)
(ii) Xanthophyceae (Yellow-
green algae)
(iii) Chrysophyceae
(iv) Bacillariophyceae (Diatoms)
(v) Cryptophyceae
(vi) Dinophyceae
(Dinoflagellates)
(vii) Chloromonadineae
(viii) Euglenineae (Euglenoids)
(ix) Phaeophyceae (Brown
algae)
(x) Rhodophyceae (Red algae)
(xi) Myxophyceae or
Cyanophyceae (Blue green
algae)

12.
GENERAL
CHARACTERISTICS
OFALGAE

13.
BRYOPHYTES
 HABITAT – Shady, moist, cold places in groups. Some –
bogs and swamps. Commonly noticed in damp soils,
rocks, wall etc.
 STRUCTURE – Non-vascular terrestrial plant of moist
habitat.
• They represent two distinct morphological generations –
Gametophytic & Sporophytic phase.
• Plant body is differentiated more than an algae.
• Primitive form i.e. they lack stem, leaves and roots –
Riccia and Marchantia.
• They comprises of a thalloid – attached to substratum –
through unicellular, unbranched rhizoids.
• In Funaria – rhizoids – branched, multicellular and
septate obliquely.

14.
• Bryophytes are called AMPHIBIANS OF THE PLANT KNGDOM.
• They require an external layer of water for dehiscence of antheridia,
swimming of male gametes to reach archegonia.
#BENEFITS OF DAMP DWELLING OF BRYOPHYTES-
1. Absence of true roots, water is absorbed directly from the ground or
atmosphere.
1. Water facilitates fertilization for Antherozoid movement.
#MODE OF REPRODUCTION –
• VEGETATIVELY – Tubers, gemmae, fragmentation etc.
• SEXUAL – Oogamous.
• Sex organs – Multicellular; Male – Antheridium (Biflagellate
ANTHEROZOIDS), Female – Archegonium (Flask shaped.
Produces single egg.)

15.
• Structure of Archegonium comprises of –
1. Dilated, swollen part – VENTER (encloses egg)
2. Slender, elongated upper part – NECK.
Archegonium and antheridium both are jacketed.

16.
• Fusion of both the gametes forms a zygote
which does not undergo reduction division
immediately instead forms/ develops into
a SPOROGONIUM/ SPOROPHYTE.
#SPOROPHYTE –
• They are dependent upon photosynthetic
gametophyte for nourishment.
• Sporogonium differentiates into –
i. Foot
ii. Seta
iii. Capsule.
• Riccia – foot and seta = absent.
• Capsule – embedded in thallus
• Sex organs – inside the thallus.
CAPSUL
E
• Meiosis occurs in
Spore Mother
Cell
SPORES • (n)
GAMETOPHYTE

17.
CHARACTERS SPOROPHYTE GAMETOPHYTE
DEFINITION
Multicellular, diploid structure
in the life cycle of a plant.
Multicellular, haploid structure
in the life cycle of a plant.
PLOIDY 2n n
FORMATION From zygote Due to germination of spore
PRODUCTION Produces spores after meiosis
Produces gametes without
meiosis
REPRODUCTION
Takes part in asexual
reproduction.
Takes part in sexual
reproduction.
DEVELOPMENT They form gametophyte. They form diploid zygote.

18.
LIVERWORTS –
• The thallus is dorsiventral and closely appressed to the substrate. The
leafy members have tiny leaf-like appendages in two rows on the
stem-like structures.
• Asexual reproduction in liverworts takes place by fragmentation of thalli,
or by the formation of specialised structures called GEMMAE
(sing, gemma). Gemmae are green, multicellular, asexual buds,
which develop in small receptacles called GEMMA CUPS located on
the thalli. The gemmae become detached from the parent body and
germinate to form new individuals.
• During sexual reproduction, male and female sex organs are produced
either on the same or on different thalli.
CLASSIFICATION OF BRYOPHYTES

19.
MOSSES –
• The gametophyte which consists of two stages.
• The first stage is the PROTONEMA stage, which
develops directly from a spore.
• The second stage is the leafy stage, which develops from
the secondary protonema as a LATERAL BUD. They
consist of upright, slender axis bearing spirally
arranged leaves.
• They are attached to the soil through multicellular and
branched RHIZOIDS. This stage bears the sex organs.
• Vegetative reproduction - fragmentation and budding
• In sexual reproduction, the sex organs antheridia and
archegonia are produced at the apex of the leafy shoots.
• After fertilisation, the zygote develops into a
sporophyte, consisting of a foot, seta and capsule.

20.
CLASSIFICATION OF BRYOPHYTES
FEATURES HEPATICOPSIDA ANTHOCEROTOPSIDA BRYOPSIDA
COMMON NAME Liverworts Hornworts Mosses
GAMETOPHYTIC PLANT
BODY
May be thallose or foliose,
unicellular rhizoids
Thallose, unicellular rhizoids
Thalloid protonema & leafy
gametophore, multicellular
rhizoids with oblique septa
SEX ORGANS
Present on dorsal surface of
thallus
Present on dorsal surface of
thallus
Develop from the superficial
cells at the apex of leafy
gametophore
SPOROPHYTE OR
SPOROGONIUM
Differentiated into foot, seta &
capsule
Differentiated into foot, short-
meristematic region and capsule
Differentiated into foot, seta
and capsule
ELATERS
Generally present, absent in
some like Riccia
Pseudo elaters are present in the
capsule
Absent
SPOROGENOUS TISSUE Develops from endothecium
Develops from amphithecium &
endothecium forms sterile
columella
Develops from outer layer
from endo-thecium, inner
layer forms sterile columella
DEHISCENCE OF CAPSULE Irregular Irregular Regular
EXAMPLES
Riccia, Marchantia,
Sphaerocarpus etc.
Anthoceros, Notothylus,
Megaceros etc.
Sphagnum, Funaria,
Polytrichum etc.

21.
1. Gametophyte –
Dominant phase
2. Undifferentiated plant
body
3. Rhizoids – absorbing &
anchoring organs
4. Vascular & Mechanical
tissue - absent
5. Internal fertilization
6. Sexual reproduction -
Oogamous
7. Sex organs –
multicellular & jacketed
8. Sporophytic phase -
lengthy
9. Sporogonium formation
takes place
10. Heterologous &
haplodiplontic alteration of
generation
GENERAL
CHARACTERISTICS
OFBRYOPHYTES
ECONOMIC
IMPORTANCE
1. Some mosses provide
food for herbaceous
mammals, birds and
other animals.
2. Species of Sphagnum, a moss,
provide peat that have long been
used as
fuel, and because of their capacity
to hold water as packing material
for transshipment
of living material.
3. Mosses, along with lichens are
the first organisms to colonize
rocks and hence, are of great
ecological importance. They
decompose rocks making the
substrate suitable for the growth
of higher plants.
4. Since mosses form dense mats
on the soil, they reduce the impact
of falling
rain and prevent soil erosion

22.
PTERIDOPHYTA
• The pteridophytes are flowerless, seedless, spore producing vascular plants which have successfully
invaded the land with true – leaves, stem and roots.
• Intermediate position – B/w bryophytes and Spermatophytes.
• Called as VASCULAR CRYPTOGAMS.
GENERAL CHARACTERS –
HABITAT – Plants – annual or perennials.
• Most of them are terrestrial and thrive in cool,
moist and shady places.
• Xeric – Selaginella lepidophylla.
• Aquatic - Azolla, Marsilea, Salvinia
• Epiphytic - i.e. growing on large trunks of trees.
Eg: Lycopodium
Selaginellalepidophylla
Azolla
Lycopodium

23.
PTERIDOPHYTES
MEGAPHYLLOU
S
Large
leave
Eg: Ferns
MICROPHYLLO
US
Small leaves
Eg: Equisetum &
Selaginella, Lycopod
etc.
• Adiantum fern – MAIDEN HAIR FERN.
• It is also called as
WALKING FERN.
Equisetum
Selaginella

24.
THE PLANT BODY/ ADULT
SPOROPHYE
• They bear an independent sporophyte with vascular system.
• Exhibit variation in form, size and structure.
• Plant body is differentiated into true stem, root and leaves.
• Psilophylates – Eg: Rhynia
• Psilotales – Eg: Psilotum
• Plants – Dorsiventral or radial in symmetry.
• Bear dichotomously or laterally branched stem.
• Roots – Adventitious
• Primary root – short lived.
• In pteridophytes, the xylem consists of only tracheids
and phloem consists of sieve cells only.
• Secondary growth is not seen in Pteridophytes
due to absence of cambium. Except – Isoetes.
} True roots & well developed
leaves = Absent

25.
Isoetes

26.
# REPRODUCTION IN PTERIDOPHYES –
• The sporophyte (2n) shows
asexual reproduction and
produces spores (n) by
meiosis from which
the gametophyte develops.
• The gametophyte (n) is
recessive but independent,
and reproduces sexually.
• Product of sexual
reproduction, i.e. zygote (2n)
produces Sporophyte (2n)

27.
 Spores are produced in special
multicellular structures called
SPORANGIA in spore mother cell.
 These sporangium development may be-
1. EUSPORANGIATE – Develops from
several sporangial initials. Eg:
Psilotum, Lycopodium, Selaginella,
Equisetum etc.
2. LEPTOSPORANGIATE – Develops
from single sporangial initial. Eg:
Marsilea, Pteris etc.
 Sporangia in some cases may be produce
in specialized structures –
SPOROCARPS.
 Spores when borne on stem – CAULINE
or on leaves – FOLIAR.
 The sporangia are produced by leaf-like
appendages called SPOROPHYLLS.
 In some cases, sporophylls may form
distinct compact structures called
STROBILI or CONES (Selaginella,

28.
• Sometimes sporangia are present in groups – SORI.
• The spores germinate to give rise to inconspicuous, small but
multicellular, free-living, mostly photosynthetic thalloid
gametophytes called PROTHALLUS.
• The gametophytes bear male and female sex organs called
ANTHERIDIA and ARCHEGONIA, respectively.
• Genera like - Selaginella and Salvinia which produce two kinds of
spores, MACROSPORE – Female gametophyte and MICROSPORE
– Male gametophyte.
• The development of the zygotes into young embryos take place
within the female gametophytes.
• Sporophyte – Dominant phase.
GAMETOPHYTE
• Sorus may be covered/ protected by
–
1. FALSE INDUSIUM – Eg: Pteris.
2. TRUE INDUSIUM – Eg:
Dryopteris.

29.
• When gametophytes are retained within original spore case –
ENDOSPORIC.
Eg: Selaginella, Isoetes, Marsilea.
• When gametophytes grow upon the soil and form independent
plants – EXOSPORIC.
Eg: Psilotum, Pteris, Lycopodium.
• The gametophytes are generally highly reduced in heterosporous
pteridophytes. Eg: Selaginella, Marsilea, Azolla.
• Sexual reproduction – Oogamous.
• The Pteridophytes, apart from normal way of reproduction, also
sometimes show following methods:
1. APOGAMY- It is the development of the sporophyte
without the fusion of the male and female gametes. It arises
directly from the gametophyte. Here the sporophyte is haploid.
2. APOSPORY- It is the development of the gametophyte from any
cell of the sporophyte other than the haploid spores. Such a
gametophyte is diploid in nature.

30.
CLASSIFICATION OF PTERIDOPHYTES
PSILOPHYTA
(WISK FERNS)
1. Primitive land plants.
2. Green upright
branches, underground
stem – rhizome.
3. Roots & true leaves
= Absent.
4. Grow in warmer
parts.
Eg: Psilotum.
LYCOPODOPHYTA
(CLUB MOSSES)
1. Small & grow close
to ground in forest.
2. Cones produced –
near the tips of
branches.
3. Grows abundantly
in mountainous part.
Eg: Lycopodium,
Selaginella.
EQUISETOPHYTA
(HORSE TAILS)
1. Hollow, upright
jointed branches –
grow up from
underground stem.
2. Leaves not large &
green.
3. Produce
sporophylls arranged
in cones.
Eg: Equisetum.
FILICOPHYTA
(FERNS)
1. Includes true
ferns like –
Adiantum, Pteris,
Nephrolepis.
2. Underground
stems which
produces leaves
above the ground.
3. Sori +nt on lower
leaf surface.

31.
GENERAL
CHARACTERISTICS
OF
PTERIDOPHYTES
1. Vascular cryptogam.
2. Sporophyte – dominating phase
3. Plant body differentiated into –
roots, stem and leaves
4. The branching is never axillary.
5. Vascular tissue makes its
appearance
6. Homosporous or heterosporous
7. Sexual reproduction - Oogamous
8. Antheridium – sessile & reduced
in size
9. Diplohaplontic – alteration of
generation +nt
10. Spores produced inside the
sporangia on leaves

32.
GYMNOSPERMS
• They are non-flowering plants producing
naked seeds (fruits are not produced).
• The gymnosperms are plants in which the
ovules are not enclosed by any ovary wall and
remain exposed, both before and after
fertilisation.
#HABIT, HABITAT &
DISTRIBUTION
1. Though small group, yet constitute ancient
group of plants.
2. Woody plants, w/o flowers, bear seeds on the
inner side of scale like leaves that are
usually arranged spirally to form cone.

33.
3. Four orders of gymnosperms with
living members are –
4. Xylem is composed of – Tracheids.
Phloem is composed of – sieve cells.
5. They are perennials and woody
plants.
6. They bear tap roots.
7. Leaves – may be of one kind or two
i.e. foliage or scale leaves.
8. Leaves may be reduced – Ephedra,
needle like – Pinus or large &
pinnately compound – Cycas.
9. Ovules – Orthotropous & covered
by single integument.
10. Female gametophyte is made up of
n endosperm on which 2-8
archegonia are +nt.
12. Syngamy occurs and forms –
Oospore (2n).
13. Oospore forms – embryo.
14. Polyembryony – common.
15. Ovules – seeds.
16. Seeds – two or more cotyledons.
17. The gymnosperms are
heterosporous; they produce
haploid microspores and
megaspores.
18. Two types of sporophylls –
microsporophylls &
megasporophylls. They from –
pollen cones (male cones) &
seed cones (female cones)
respectively.

34.
GYMNOSPERMS
CYCOPSIDA
(Cycas)
1. Found in warm weather.
2. Either short, tuberous,
underground stems or erect,
cylindrical stems above the ground
with large, compound divided leaves.
3. Plants- dioecious.
GINKGOPSIDA
(Ginkgo biloba – living
fossil)
CONIFEROSPSIDA
(Pinus)
GNETOPSIDA
(Gnetum)
1. Include pine, cedar, spruce, fur & red wood trees.
2. Found in Himalayas.
3. Needle – like leaves adapted for conditions.
4. They bear 2 types of cones – one producing pollen
grain & the other egg.
5. Araucaria – ornamental plant.
6. Pine nuts – edible.
7. Resin secreted by Pinus – Tar & turpentine making.
8. Favouring alcohol beverages – Berries of Juniper.

35.
Cycas
Ginkgobiloba
Pinus
Gnetopsida
Araucaria

36.
Pinus
#MODE OF REPRODUCTION –
HETEROMORPHIC
ALTERNATION OF
GENERATION.
 Sporophyte – diploid
dominant
independent
 Gametophyte – haploid
recessive
dependent

37.
• The pollen grain is released from the microsporangium. The pollination in Gymnosperm is
anemophilous (wind pollination). The pollen grains come in contact with the opening of the
ovules borne on megasporophylls.
• The pollen tube carrying the male gametes grows towards archegonia in the ovules and
discharge their contents near the mouth of the archegonia. Following fertilization, zygote
develops into an embryo and the ovules into seeds. These seeds are not covered.
• The fertilization is direct as the pollen grains are received directly in the pollen chamber of the
ovule. Fertilization is achieved through a pollen tube. This process is called SIPHONOGAMY.

38.
GENERAL
CHARACTERISTICS
OFGYMNOSPERMS
1. Naked seeds
2. Heterosporous – life
cycle
3. Better adaptation
for land habitat
4. Fertilization -
siphonogamous
5. Shows secondary
growth – due to
cambium
6. Seeds are borne on
cones
ECONOMIC
IMPORTANCE
1. Ornamentals
2. Food articles
3. Wood
4. Medicinal values
5. Resin and oils
6. Other uses

39.
ANGIOSPERMS
HABIT & HABITAT – Flowering plants.
• Include – trees, shrubs, vines and herbs.
• Mostly – terrestrial but some are hydrophytes
like hydrilla, water lilies etc. many are even
xerophytes – behave as EPHEMERALS. Some
epiphytes – Orchids. Parasites – Cuscuta.
Saprophytes – coral root orchid.

40.
DEVELOPMENT OF FRUIT & FLOWER
• Sporophytic plant – bears flowers which are modified
shoot and sexual reproductive organ.
• Flowers bear – Sepals, petals, stamens and carpels
which arise from thalamus.
• Stamen comprises of – Anther and filament.
• Carpel – Stigma, style and ovary.
• Anthers produces pollen grains.
• In angiosperms, seeds are produced and enclosed by
fruits.
• Wolffia is the smallest angiosperm, l mm in size and
Eucalyptus grows to over 100 meters.

41.
LIFE CYCLE OF AN ANGIOSPERM
• The plant body is
differentiated into root,
stem and leaves.
• It has flowers, fruits and
seeds.
• Vascular tissues are well
developed.
• Xylem shows vessels or
tracheae while phloem
has sieve tubes and
companion cells.

42.
GENERAL
CHARACTERISTICS
OFANGIOSPERMS
1. They produce
flowers.
2. Seeds are covered.
3. Double fertilization
occurs.
4. Ovary ripens into
fruit which contain
seeds.
5. Reduced
gametophytic phase.

43.
PLANT LIFE CYCLES & ALTERATION OF
GENERATIONS
• The haploid plant body (gametophyte)
produces gametes by mitosis.
• Zygote produces sporophytic plant body by
mitosis.
• This sporophytic plant body produces spores
by meiosis.
• These spores again divide mitotically to
produce haploid plant body.
• Life cycle consists of two distinct
morphological phases –
• When gametophytic & sporophytic stages are
morphologically similar – ISOMORPHIC
ALTERATION OF GENERATION.
• When they are morphologically dissimilar –
HETEROMORPHIC ALTERATION OF
GENERATION.
PHASES
In Plant life cycle
GAMETOPHYTIC
Haploid
SPOROPHYTIC
Diploid

44.
PLANT LIFE CYCES
HAPLONTIC
1. 1. Sporophytic generation
– one celled zygote.
2. 2. Zygote – meiosis –
spores (n).
3. 3. (n) Spore – mitotically
– gametophyte.
4. 4. Gametophyte (n) –
Dominant, photosynthetic
phase
5. Ex: Volvox, Spirogyra,
Chlamydomonas (some
species)
1. Sporophyte phase
– Dominant,
photosynthetic,
independent.
2. Gametophytic
phase – single to
few celled (n)
gametophyte.
Ex: Angiosperms &
gymnosperms.
DIPLONTIC HAPLODIPLONTIC
1.Intermediate condition b/w
(n) & (2n).
2. Both phases – multicellular.
3. Gametophyte (n) - A
dominant, photosynthetic,
thalloid or erect phase.
Alternates with -
4. Sporophytic phase - Short
lived multicellular, totally or
partially dependent upon
gametophyte for anchorage &
nutrition.
Ex: Bryophytes
1. Sporophyte (2n) –
Dominant,
independent,
vascular plant body.
Alternates with –
2. Gametophyte (n) –
multicellular,
saprotrophic/autotro
phic, independent,
short lived.
Ex: Pteridophytes.
Some algae –
Ectocarpus,
Polysiphonia, Kelps.