classification of anImalia kingdom with chart
Answers
basis of classification
There is a difference in structure and form of different animals, there are a few fundamental characteristics that are common to various organisms. The features are
Arrangement of cells,
Body symmetry,
Nature of coelom,
Patterns of digestive, circulatory and reproductive systems,
Arrangement of cells in germ layers,
Segmentation,
Notochord. These are the features that forms basis for animal classification.
Levels of Organisation
All the organisms of the Animal kingdom are multicellular but they do not exhibit the same pattern if organization of cells.
The patterns of cellular organization seen in animals are:
Cellular Level of Organization - In these animals the cells are arranged in the form of loose cell aggregates. This kind of cellular organization is seen in sponges.Example: Sponges.
Tissue Level of Organization - Cells of the animals show division of activities among themselves. Cells performing the same function are arranged as tissues. Example: Coelentrates.
Organ Level of Organization - Tissues of the animals performing the similar function are grouped to form organs. Each organs is specialized for specific function. Example: Platyhelminthes.
Organ system Level of Organization - In animals where organs have associated to form functional systems where each system is concerned with a specific physiological function are said to exhibit organ system level of organisation. Example: Annelids, Arthropods, Molluscs, Echinoderms and Chordates.
Animal Classification
Patterns of Organ Systems
Organs systems in different groups of animals exhibit various patterns of complexities.
Digestive System - There are two patterns of digestive system incomplete and complete digestive system.
Incomplete digestive system - This pattern of digestive has only one opening to the outside of the body, i.e., a single opening serves as both mouth and anus. Example: Platyhelminthes.
Complete digestive system - In this pattern there are two opening to the outside of the body, the mouth and the anus. Example: Arthropods, Chordates, etc.
Circulatory System - Circulatory system may be of two types - open type and closed type.
Open type - In open type circulatory system the blood is pumped out of the heart and the cells and tissues are diectly bathed in it.
Closed type - In this type of circulatory system the blood is circulated through a series of vessels of varying diameters - the arteries, veins and capillaries.
Body Symmetry
Animals can be categorized on the basis of their body symmetry. The arrangement of body parts around a central point or line determines the symmetry.
Asymmetrical - some animals cannot be divided into two equal halves along any plane passing through the center of the organism. Asymmetry is the complete absence of symmetry. Example: Sponges.
Radial Symmetry - Animals are said to exhibit radial symmetry, when any plane passing through the central axis of the body divides the organism into two identical halves. Example: Coelentrates, ctenophores and echinoderms.
Bilateral Symmetry - Animals where body can be divided into identical right and left halves are said to be bilaterally symmetrical. Example: Annelids, Arthropods,etc.