Class 9 Science Note
Classification of Plants and Animals
Livings being are generally classified into two kingdoms. They are:
1. Plant kingdom
On the basis of the flowering and non flowering, the plants kingdom are divided into two sub - kingdom.
a. Cryptograms: They are non flowering plants. On the basis of their appearance they are divided into three divisions:
They are very small undeveloped plants
The plant body is not differentiated into, stem, root and leaves.
Reproduction takes place through spores and gametes.
They are unicellular or multiellular.
Thallophytes are further divided into two sub-divisions:
They are autotrophs.
Chlorophyll is present.
They are green filamentous plants.
They are heterotrophs.
Chlorophyll is absent.
They grow in moist places.
Life cycle completes by the alternation of generation
They are the developed plants in comparison to thallophyta.
The plant body is differentiated into stem and leaves and roots are not present.
Vascular tissue is absent.
The body is differentiated into roots, stem and leaves.
Complex tissues xylem and phylum are well developed.
They are mostly found and cool and damped places.
Reproduction takes place by the means of spores developed in sporangia.
b. Phanerogams: Phanerogams are the developed seed bearing and flowering plants
It is further divided into two sub divisions:
Sub division Gymnosperms:
They are cone bearing plants.
They grow in dry places.
They bear naked seeds.
Pollination takes place through wind.
Sub division Angiosperms:
They grow both in land and water.
They bear developed flowers.
Their seed are enclosed in true fruits.
They may be herbs, shrubs and trees
2. Animal kingdom
Animal kingdom is divided into two groups:
Vertebrates: Those animals having vertebral column are called vertebrates. They can either be cold blooded like fish amphibian or warm blooded animals like aves.
Invertebrates: Those animals having no vertebral column are called Invertebrates. They are classified into 9 major phyla:
It is unicellular microscopic organism.
Digestion is intracellular.
Respiration takes place through the general body surface.
Locomotion takes place through the locomotory organ like cilia and flagella.
Porifera are the organism having pores.
Digestion occurs within the cell.
Reproduction occurs sexually and asexually.
Body is cylindrical, assymetrical and radially symmetrical.
They have body cavity.
They are mostly aquatic found in fresh water.
They are characterized by their stinging cells.
Locomotion takes place through tentacles.
They are soft bilaterally symmetric al animals
Digestive respiratory and circulatory system is absent.
They are hermaphrodites.
They are round in shapes and found in fresh water and damp soil.
They are triploblastic animals.
Their alimentary canal, mouth and anus can be easily distinguished.
They have circular bands and their body is divided into different segments.
Respiration takes place through skin.
Excretion takes p;ace through nephridia.
Body is divided into head thorax and abdomen.
Excretion takes place through malphigian tube.
Circulatory system consists of dorsal heart with arteries only.
They are mosltly acquatic.
Respiration takes place through gills
Alimentary canal is well developed.
Locomotion takes place through the well muscled feet.
Surface body is covered with spines
Mouth lies on the ventral surface.
Locomotion takes place through tube feet.
Body covering is made up of calcium carbonate.