Phanerogams. These plants which have well differentiated reproductive tissues and bear seeds are included in phanerogams. Their plant body is differentiated into root, stem, and leaves. They also have well developed vascular system (xylem and phloem). They have multicellular sex organs. Their embryo develops from a fertilized egg.

Eichler (1883) suggested that the plant kingdom should be divided into two following subkingdoms:
(i) Sub-kingdom Cryptogamae (Crypto-hidden, gamous-marriage).
(ii) Sub-kingdom Phanerogamae (Seed bearing plants).

(a) Pinus is a phanerogam, it produces seed, while the others are cryptogam and have naked embryos.
(b) Octopus belongs to the phylum Mollusca while the others belong to phylum Echinodermata.

Characteristic is a particular from or a particular function. For example, generally human being has five finger in each hand. Thus, presence of five finger in each hand is a characteristic. Similarly, animals can run but trees like banyan tree cannot run, is also a characteristic.

Range of Variations
(i) Life span-Mosquitoes live for a few days whereas cow, dog, etc. live for many years.
(ii) Colour-Some organisms like certain cows, horses, dogs are white but some birds and flowers are brightly coloured.
(iii) Size-Some organisms are so small that we cannot see them with naked eyes. On the other hand, eucalyptus tree is several metre tall.

The basis for grouping organisms into five kingdoms are:
(i) Whether the organisms are made of prokaryotic or eukaryotic cells.
(ii) Whether the organism is unicellular i.e., a cell living singly or organised into multicellular and thus complex organisms.
(iii) Whether the cells have a cell wall or not.
(iv) Whether they prepare their own food or get their food from outside.

In spite of certain external differences, plants and animals show a number of very obvious similarities which are as follows:
(i) Plants and animals are made up of microscopic units-the cell.
(ii) Both contain living substance protoplasm.
(iii) Certain life processes i.e., respiration, digestion, reproduction, assimilation etc. take place in both the groups in identical manner.
 (iv) Both show response to external stimuli.
(v) They both show growth.
(vi) Both reproduce and pass on their hereditary characters to the offspring by the same mechanism.

The practice of naming is one of the greatest inventions of man. Millions of animals and plants are named differently in different languages in different parts of the world. It means the names used for one organism differs from place to place. For example, Argemone a common weed has as many as ten to twele Hindi names alone. Some call it 'Firangi Dhatura', Sial Kanta', 'Pila Dhatura', 'Bharband', 'Kandhari', 'Satya nasi buti', 'Katela', 'Jahriber', 'Ugar Kanta' etc. Same thing is applicable to animals and other plants. Sometimes the common names are misleading. Same name may be used for different organisms in different parts.
To avoid this confusion Linnaeus gave a system in which an organism is given a name with two components-the first part is the generic name and the second part is the specific name. Thus the scientific name of common cat is Felis domestica, and that of tiger is Felis tigris. This system of giving a name with two components to an organism is called 'Binomial system of nomenclature'. The scientific names thus given to the organism are recognized all over the world. Hence, confusion is avoided on this aspect.

(a) Definition of classification. Arranging the things on the basis of similarities and differences in various groups is known as classification.
Significance of classification:
(i) Classification helps us in exploring the diversity of life forms.
(ii) Classification of organism indicates the interrelationship amongst different groups of organisms. Thus classification of life forms is related to their evolution.
(b) Plant                    Plant Division
(i)  Spirogyra             Thallophyta
(ii)  Fern                    Pteridophyta
(iii) Funaria                Bryophyta
(iv) Pinus                   Gymnosperm
(v) Apple tree             Angiosperm
(vi) Mustard plant       Angiosperm

Plants and Animals differ as given in the table below: