Classification of Plants
Classification of Plants
Classification of Plants
Introduction
Robert Whittaker (1959) proposed five kingdom system of classification for
the study of living organisms .According to Whittaker the five kingdom are
monera , Protista , fungi, plantae and Animalia.
Botanists’ scientist named eichler in 1883 classified the kingdom plantae as
cryptogams and Phanerogams.
Basis for classification-
1) Presence or absence of organs.
2) Presence or absence of separate conducting tissues for conduction
of food and water.
3) Presence or absence of seeds in plants.
4) Whether seeds are enclosed in fruits or not.
5) Number of cotyledons in seeds: one or two i.e.- monocots and dicots.
Sub-kingdom –cryptogams-
Plants belonging to sub –kingdom cryptogams reproduce with the help of
pores.
1) Division I – Thallophyta
1. Plants belonging to this group grow mainly in water. Some grow in fresh
water, while some in marine water.
2. These plants do not have specific parts like roots, stem, leaves and
flowers.
3. They are autotrophic owing to the presence chlorophyll such plants are
called algae.
4. Algae show great diversity. They are either unicellular or multicellular
some are microscopic while others are macroscopic i.e.- large.
Eg- spirogyra, ulothrix, ulva, chara, sargassum etc.
Different types of fungi such as yeast and moulds which do not possess
chlorophyll have also been included in this group.
2) Division II- Bryophyta.
1. Plants belonging to this group are amphibious, because they
grow on moist soil but require water for reproduction.
2. Plants are thalloid multicellular and autotropic.
3. They reproduce by spores.
4. The structure of plant body is long ribbon like and flat without
true roots, stem and leaves.
LESSON NO 6-CLASSIFICATION OF PLANTS.
Instead of these, they possess stem like or leaf like parts,
besides root like rhizoids.
5. They lack specific tissues for the conduction of food and water.
Eg- Funaria, Riccia, Marchantia, Anthoceros etc.
2) Division III- Pteridophyta
1. Plants belonging to this group bears well developed roots, stem
and leaves.
2. They do not bear flowers and fruits.
3. They bear separate tissues for the conduction of food and water.
4. They reproduce by means of spores which are formed on the
posterior side of their leaves.
5. Eg- Nephrolepis (fern), Adiantum, Pteris, Marsilea, Selaginella,
Equisetum, Lycopodium etc.
6. Reproduction in pteridophytes occur asexually by spores and
sexually by zygote formation.
Sub-kingdom – Phanerogams.
1) These are characterised by the presence of flowers, fruits, and
seeds.
2) They are classified as gymnosperms and angiosperms.
3) In gymnosperms the seeds are naked while in angiosperms the
seeds are enclosed in fruits.
1) Division I- Gymnosperms.
1. Gymnos – naked , sperms-seeds
2. Gymnosperms are perennial, woody and evergreen plants.
3. The stems of gymnosperms are unbranched.
4. The leaves form a crown at the top of the plant.
5. They bear male and female flowers on different sporophylls of the
same plant.
6. Seeds are not enclosed in fruits.
7. Eg- Cycas, thuja (Morpankhi), Picea (Christmas tree), Pinus (Deodar)
etc.
2) Division II- Angiosperms.
1. Angios means – concealed or hidden, sperms – seeds.
2. Angiosperms are those plants in which seeds are hidden.
LESSON NO 6-CLASSIFICATION OF PLANTS.
3. These plants possess all organs.
4. Flowers are reproductive organs of these plants.
5. Angiosperms are divided into two groups, viz- monocots and dicots
depending on the number of cotyledons in their seeds.
Q2) Write a short note on spirogyra and draw a sketch and label it.
Ans- 1. Spirogyra is a green filamentous alga belonging to the division
Thallophyta.
2. It grows in fresh water.
3. The presence of chlorophyll, it synthesises its food by the presence of
photosynthesis.
4. It contains spirally arranged thread like chloroplast in its cells.
5. In each chloroplast, there are number of rounded bodies surrounded
by starch. These rounded bodies are called pyrenoids.
LESSON NO 6-CLASSIFICATION OF PLANTS.
Q4) Explain in brief about Marchantia and draw a label sketch of it.
Ans- 1. Marchantia is a bryophyte.
2. Marchantia is called amphibious plant, as it shares two habitants, viz soil for
its growth and water for reproduction.
3. It is flat ribbon like long and without true roots, leaves and stems.
4. Instead of roots, its bear’s rhizoids.
LESSON NO 6-CLASSIFICATION OF PLANTS.
5. It lacks conducting tissues which conducts food and water.
Q5) Explain in brief about Funaria and draw a label sketch of it.
Ans- 1. Funaria is a bryophyte.
2. Like Marchantia, Funaria is also amphibious.
3. The plant body of Funaria is differentiated into stem-like, leaf-like and root-
like rhizoids.
4. It develops a capsule on a stalk during favourable conditions.
5. Spores are formed inside the capsule. The spores give rise to new plants.
LESSON NO 6-CLASSIFICATION OF PLANTS.
Q6) Write a short note on fern and draw a label sketch of it.
Ans- 1.Ferns are ornamental plants seen in gardens.
2. They are called ornamentals as they beautify the place wherever they grow.
3. Since they grow in gardens they do not bear flowers and fruits, they bear
different types of attractive leaves.
4. They reproduce by spores which develop on the lower side of their leaflets
in the form of sori.
LESSON NO 6-CLASSIFICATION OF PLANTS.
Q7) Write the characteristics of subkingdom Phanerogams.
Ans- 1. Plants that bear seeds are called Phanerogams.
2. In these plants, seeds are formed after reproduction.
3. The seeds contain embryo and stored food.
4. The stored food is used during germination for the growth of the embroys.
5. Phanerogams are divided into two groups, viz gymnosperms and
angiosperms depending upon whether the seeds are enclosed in a fruit or not.
Kingdom: Plantae
Cryptogams Phanerogams
Thallophyta Pteridophyta
Bryophyta
Angiosperms
Gymnosperms
Monocotyledons
Dicotyledons
Eg- Maize
Eg- Mustard
LESSON NO 6-CLASSIFICATION OF PLANTS.
Q3) Complete the flow chart-
Living organisms
Prokaryotic Eukaryotic
Monera
Unicellular Multicellular
Protista
Animalia
Autotrophs
Heterotrophs
Plantae
Fungi
LESSON NO 6-CLASSIFICATION OF PLANTS.