The Plant Kingdom is characterized by autotrophic organisms that produce their own food, have cell walls, chloroplasts, and vascular tissue. Plants are classified based on their plant body, vascular system, and seed formation. The divisions include cryptogams (non-flowering) such as algae, fungi, lichens, bryophytes, and pteridophytes, as well as phanerogams (seed-bearing) such as gymnosperms and angiosperms. Angiosperms are further divided into monocots and dicots.

1. PLANT KINGDOM

2. Characteristics of Plant Kingdom
 The following features characterize the Plant Kingdom-
• They are non-motile.
• They are called autotrophs because they make their food.
• They reproduce asexually through vegetative propagation or through sexual methods.
• Organisms in the Plant Kingdom are multicellular, eukaryotic organisms.
• All the plant cells contain an outer cell wall and a large central vacuole.
• Plants contain a green photosynthetic pigment called chlorophyll.
• The chlorophyll is present in the chloroplasts.
• All the plants in the Plant Kingdom have different organelles for reproduction, support,
anchorage, and photosynthesis.

3. Cryptogams and Phanerogams
 Cryptogams- These are the non-flowering and non-seed bearing plants. For
example – Thallophyta, Bryophyta, and Pteridophyta.
 Phanerogams- These plants have flowers as well as seeds. For example –
Gymnosperms and Angiosperms.

4. Classification of Plant Kingdom
 Plant body: It means that plants are classified based on the presence or
absence of a well-defined plant body or parts of a plant. E.g., leaves, stem, and
root.
 Vascular system: Whether a certain type of plant has a vascular system (Xylem
and phloem) that is responsible for the transportation of water and other
substances.
 Seed formation: Whether the plants can have seeds and flowers and whether
the seeds are naked or enclosed.

7. 1. Thallophyte
 The Plant Kingdom has a division called Thallophyta, which includes primitive forms of plant life.
These forms show a simple plant body. This particular division includes unicellular to large algae,
fungi, and lichens.
I. Algae
• Algae contain chlorophyll and hence are autotrophic.
• Algae are mostly present in aquatic life forms.
• They also occur in various habitats: wood, moist stones, and soils.
• Sometimes, Algae also occurs in association with fungi and are called Lichens.
• Their asexual reproduction is by fragmentation.
• Their sexual reproduction takes place through the formation of gametes.
• Algae is further divided into Chlorophyceae, Phaeophyceae, and Rhodophyceae.

8. Contd….
II. Fungi
• Fungi are eukaryotic organisms that also include microorganisms such as mold, yeasts, and
mushrooms.
• They do not have chlorophyll.
III. Lichens
• Lichens formed a symbiotic relationship between algae and fungi.
• These organisms are of considerable economic importance.

10. 2. Bryophyta
 Bryophytes include mosses and liverworts. They grow in moist areas in the
hills.
 They are typically called amphibians of the Plant Kingdom.
 Bryophytes depend on water for sexual reproduction.
 Their bodies are now advanced and well-differentiated from Algae.
 They are attached to the substratum by rhizoids (unicellular or multicellular).
 The main body of the plant is a haploid.
 They are called gametophytes as they produce gametes.

11. Reproduction in Bryophytes
• The sex organs are multicellular.
• The male sex organ is called the antheridium.
• The archegonium is known as the female sex organ.
• Both the male sex organ as well as the female sex organ are fused in the water
for fusion.
• The antherozoid fuses with the egg to form the zygote.

13. I. Liverworts
• Liverworts usually grow in moist, dirty habitats such as banks of rivers, damp
soil, marshy ground, the bark of trees, and deep in the woods.
• The plant body of a liverwort is called a thalloid, e.g., Marchantia.

14. II. Mosses
 The early stage of the life cycle of mosses is called the gametophyte. It
consists of two main stages.
• The first stage of its life cycle is known as the protonema stage. It develops
directly from a spore.
• This stage is seen as a creeping, green, branched, and usually filamentous type
of stage.
• The second stage comes from the leafy stage. It happens after the secondary
protonema, in the shape of a lateral bud. They have slender, upright axes that
bear spirally arranged leaves.

16. Funaria structure

17. 3. Pteridophyte
 They are exclusively used for medicinal purposes.
 Pteridophytes are widely grown as ornamentals.
 They have a well-differentiated plant body, including roots, stems, leaves, and
the vascular system.
 The main plant body is a sporophyte.
 They are the first-ever terrestrial plants to possess vascular tissues.
 The spores are produced by meiosis in spore mother cells.
 Pteridophytes are further divided into- Psilopsida (Psilotum), Lycopsida
(Lycopodium), Sphenopsida (Equisetum), and Pteropsida (Ferns).

20. Difference between Pteridophyte and Bryophyta
Bryophyta Pteridophyta
The plant body is haploid and gametophytic. The plant body is diploid and sporophytic.
The sporophytic generation is completely or partially
parasitic on the gametophyte.
Both sporophytes and gametophytes have an
independent existence.
The Plant body may be thalloid (like liverworts) or
with leafy appendages (in mosses).
The plant body is differentiated into roots, stems and
leaves.
Vascular tissue is absent.
Vascular tissue is present. Vessels are not present in
the xylem.
Only one type of spores are formed (all are
homosporous).
Some genera evolved the formation of two types of
spores, i.e., heterospory.

21. 4. Gymnosperms
 Gymnosperms are plants with ovules not surrounded by the ovary wall. The ovules remain exposed, both
before and after fertilization.
 Gymnosperms are woody and perennial.
 They form bushes or trees.
 Some are very large, while some are very small in size.
 The stem might be unbranched or branched.
 They have a taproot.
 They have either simple or compound leaves.
 The seeds are not entirely enclosed within an ovary or fruit.
 Gymnosperms produce haploid microspores as well as megaspores.
 Their seeds are directly open to the air, where they are fertilized by pollination.
 For example – Pinus, Cycas, Gingko.

27. 5. Angiosperms
 These plants bear seeds.
 Angiosperms have well-differentiated plant bodies.
 In these plants, the seeds are entirely enclosed by fruits.
 The male sex part is called the stamen.
 The female sex part in the flower is called the pistil or the carpel.
 Some Angiosperms are microscopic, while some are tall trees.
 The pistil contains an ovary that is enclosed by one or many ovules.
 For example – Eucalyptus, Orchids, Rafflesia, and many more.

33. Divisions of angiosperms
 Monocotyledons
• These are the types of flowering plants whose embryo has only one
cotyledon. And it is why they are called monocots.
 Dicotyledons
• These are the division of angiosperms where the flowering plant has
cotyledon in pairs.

34. Monocotyledon vs Dicotyledon
Monocotyledon Dicotyledon
The monocotyledonous embryos have a single
cotyledon
The dicotyledonous embryos have a pair of cotyledons
They have a fibrous root system They have a tap root system
Leaves in monocots have parallel venation Leaves in dicots have reticulate or net venation
In monocot flowers, the count of parts of the flower is
a multiple of three or equal to three
The count of parts in a dicot flower is a multiple of
four or five or equal to four or five
The roots and stems of monocotyledons do not
possess a cambium and cannot increase in diameter
The roots and stems of dicotyledons possess a
cambium and have the ability to increase in diameter
A few examples of monocotyledons are garlic, onions,
wheat, corn and grass, etc.
A few examples of dicots are beans, cauliflower, apples
and pear, etc.