Animal Kingdom: Classification, Phylum, Characteristics, Examples

Hello friends, do you want to know about the animal kingdom? If yes, this article is for you. In this article, you have been given step-by-step information about the animal kingdom, so let’s start reading without wasting time.

What is Animal Kingdom?

More than 10–12 lac types of animals are found on our earth, and Carolus Linnaeus first established the animal kingdom in the two-kingdom system. They divided the organism into two kingdoms: Kingdom Plantae and Kingdom Animalia.

Classification of Animal Kingdom –

Scientist George Quavier classified the animal kingdom.

He divided the animal kingdom into 31 phyla, 10 of which are big phyla called the Major Phylum and 21 of which are small phyla called the Miner Phylum. We will read 11 phyla, with 10 major phyla and 1 miner phylum.

Name of 11 Animal Phyla

Friends, you must remember these 11 phyla serially; only then will you be easy to read and understand.

Sr. No.	Phylum	Example
1	Porifera	Sycon
2	Coelenterata	Obelia
3	Ctenophora	Tinoplana
4	Platyhelminthes	Taenia (Tapeworm)
5	Aschelminthes/Nematoda	Ancylostoma
6	Annelida	Nerels
7	Arthropoda	Palaemon (Prawn)
8	Mollusca	Pila (apple snail)
9	Echinodermata	Starfish
10	Hemichordata	Balanoglossus
11	Chordata	Fish, Bird, humans, etc

Of these, Ctenophora is a miner phylum.

The basis of classification of the animal kingdom

The animal kingdom is classified on 6 bases.

1. Body organization
2. Symmetry
3. Germ Layer
4. Coelom
5. Segmentation
6. Notochord

Levels of Body Organization –

The body organization means how the body of the animals is made. Our body is made of cells, and the cells make tissue together. The tissue forms the organ, and the organ makes the organ system. That is, how is the organization of our body? It is organ system level organization because our body is getting organ system.

However, there will be some animals in which the organisms will not be found, and only if the organs are found will the organization of their body be organ-level organization. There will be some animals in which the organ will not get the tissue, and then their body will have tissue-level organization. Some will not get tissue; only if there are cells will their body have cell-level organization.

There are two types of organ system-level organization: the digestive system and the circulation system.

Digestive system – This is of two types: full digestive system and incomplete digestive system. The full digestive system is found in the 5th-11th phylum, and the incomplete digestive system is found in the 2nd, 3rd, and 4th phyla.

Circulatory system – This is also of two types: open circulation system and closed circulation system. The open circulatory system is found in the 7th-8th phylum, and the closed circulation system is found in the 11th phylum.

Symmetry –

This means that if a body is cut from an axis that goes from the body’s center, whether it is attractive or transverse or how two equal parts are found, then such symmetry is called Radial Symmetry. This symmetry is found in the 2, 3, and 9th phylum, but in the 9th phylum, this symmetry is found in the larva state.

And if the second body cuts two equal parts, then such symmetry is called asymmetry. This symmetry is first found in the union.

Such a creature whose body is found in two equal parts only after cutting from one axis, then such symmetry is called bilateral symmetry. This symmetry is found in the phylum from 4 to the 11th. The 9 is found in the larva state of the phylum.

Germ Layer –

These levels are in the embryonic state. This level is differentiated and makes up the entire body. There are three types of levels.

1. Ectoderm
2. Mesoderm
3. Endoderm

The exterior level is called the ectoderm, the middle level is called the mesoderm mesoderm, and the internal level is the Endoderm.

The animals in which these three levels are found are called Triploblastic.

Examples – From Platyhelminthes to Chordata phylum are triploblastic animals.

The animals in which Ectoderm and Endoderm are found at only two levels are called Diploblastic. In the middle of these levels, jelly-like is a substance called mesoglea.

For example, Porifera, Coeleteenrata, and Ctenophora are diploblastic animals.

Coelom –

The space between the body and gut walls is called CoelomCoelom. In these empty spaces, a hollow organ is found. Such organs that are hollow from the inside are called visceral organs.

Such as our heart, lungs, liver, brain, etc.

This CoelomCoelom is made up of the breakdown of Mesoderm.

There are three types of animals based on Coelom.

Acoelomate –

Such animals that do not contain CoelomCoelom are called Acoelomate. Such as – 1, 2, 3, and 4, which are the phylum beings. 1, 2, 3, these are diploblastic; if they do not contain the MesodermMesoderm, then the CoelomCoelom will be made from where, but the fourth phylum is triploblastic, and it includes the MesodermMesoderm. Still, where does it break the MesodermMesoderm, and where will the CoelomCoelom be made? That is, it does not make the CoelomCoelom. So, these four phyla are called Acoelomate.

Coelomate –

In such animals, the breakdown of Mesoderm is made of Coelomates. They are also called true coelomates. The level of the coelom mesoderm levels it. Examples: 6th—11th are called coelomates.

Pseudocoelomate –

Coelom is made from the sliding of the MesodermMesoderm towards the ectoderm. Example – The fifth is in the phylum beings.

Segmentation –

When the body is divided into sections, it is called SegmentationSegmentation. It is of two types.

Surface segmentation – When the Segmentation body’s surface segmentation is done only, its organs are not done, and such SegmentationSegmentation is called surface segmentation. Example – Coelenterata.

True Segmentation – When the Segmentation of the surface of the body and the limbs is also done, it is called true SegmentationSegmentation. Examples – Annelida, Arthropoda, and Chordata.

Notochord –

On the back part, there is a hard, flexible, rod-like structure called a notochord. The animals in which this notochord is found are called chordates; in which it is not, they are called Non-Chordates.Animals from 1 to 10 phylum are Non-chordates. 11 phylum, or the animals of the Chordata, are chordates.

Friends, we have read about 6 bases and will now study the phylum.

Phylum Porifera

Characteristics of Phylum Porifera

• They are aquatic. Most are found in saline water.
• These indicate asymmetry.
• Their physical organization is at the cellular level.
• They get water transport or a placenta system. Water transport means water inside these sponges, which contain nutritional substances and gases that go in from small pores, out of which nutrients are taken into use, and the waste material is removed from the large pore. Small pores are called ostia, and large holes are called the osculum.
• These are diploblastic.
• The body of these sponges comprises two levels, one of which is an external level called Pinacoderm. The ectoderm layer produces this level. Each cell of these pinacoderms is called a Pinacocyte. And the inner level is called Choanoderm. The Endoderm Layer builds it. Each cell of Choanoderm is called a Choanocyte. There are small pores between these two levels called ostia. Moreover, there is a mesoglea in the middle of these levels, called spicules or spongin fibers, in which thorny structures are found. Therefore, different classes are classified based on these spicules.
• They are classified based on skeleton or spicules.
• They are bisexual.
• These include asexual reproduction by Budding, the fragmentation method.
• Their development is indirect.
• They can regenerate.
• Examples are Sycon, Spongila (freshwater), and Spongin (Bathspang).

Phylum Coelentrata

Characteristics of Phylum Coelentrata

• They get radial symmetry in them.
• They get the physical organization of the tissue level.
• They are found in seawater, but Hydra is found in freshwater.
• In which food is digested called coelenteron. This phylum is named coelentrata, and the word coelenteron refers to it.
• They are found in bite cells on some body parts and tentacles, which help with adhesives, self-defense, and hunting.
• These have a digestive inter-cellular type. That is, it occurs inside the cell.
• Their body indicates two types of structure: a polyp or cylindrical, and the other the size of a medusa or umbrella-shaped. However, there is also a creature in this phylum, and both of these types of structures are found, named Obelia. When this animal generates asexual reproduction, the umbrella-shaped animal is formed, and when this umbrella-shaped animal makes sexual reproduction, the animal of cylindrical is formed; that is, there is a generational alternation in this animal.
• Examples – Physelia, Hydra, Obelia, Aurelia, etc.

Phylum Ctenophora

This is a small association.

The main characteristic of Phylum Ctenophora

• They are also called comb Jelly or marine walnuts because their body surface has 8 comb plates, and their structure is similar to that of walnuts.
• They have radial symmetry.
• They are diploblastic.
• Their physical organization is at the tissue level.
• The members of this phylum are called pelagic because they are found on the sea’s surface.
• They have two large tentacles, on which a special type of cell called the Laso cell (colloblast) helps capture prey.
• Digestives in these are both external and inter-cellular types.
• Bioluminescence is their main character. Bioluminescence means these organisms shine.
• They only get sexual reproduction, and they are also bisexual. In these, fertilization is external.
• Examples – Pleurobranchia, Tinoplana.

Phylum Platyhelminthes

Characteristics of the phylum Platyhelminthes

• Their back surface is flattened, so they are called flatworms.
• They contain bilateral symmetry, are triploblastic, and do not get CoelomCoelom.
• They have a physical organization at the organ level.
• They contain special types of cells called flame cells, which help with excretion. The name of the excretory organ is Protonephridia.
• Most of the animals of this phylum are internal parasites, which are found to be suckers.
• Most of the animals in it are bisexual, and fertilization is internal.
• Planaria has an immense ability to regenerate. This means that if a small part of the planaria’s body is cut off, then the planaria will become again from that severed part.
• Examples – Taenia, Faciola, Planeria, etc.

Phylum Aschelmithies (round worm)

Characteristics of phylum aschelmithies

• When the animals of this phylum are cut in transverse, they seem round; hence, they are called roundworms.
• They are aquatic, terrestrial, free, or parasites in plants and animals.
• They get bilateral symmetry.
• They are triploblastic, and they are found in pseudocolor.
• In these, the first organ system level physical organization is found.
• The diet is complete in them.
• They have an emission placenta/protonephridia; the cell inside is called a rennet cell. This cell removes waste materials from the body through excretory holes.
• The animals of this phylum are unisexual, and the females are larger than the males.
• The fertilization in them is internal.
• Examples – Ascaris, Wuchereria, Encyclostoma.

Phylum Annelida

Main characteristics of Phylum Annelida

• They are aquatic and terrestrial, free-living, or parasites in plants and animals.
• They have bilateral symmetry; these are triploblastic, and true CoelomCoelom is found in them.
• They get the physical organization of the organ system at a certain level.
• Their body is divided into sections.
• It contains vertical and circular muscles that help in movement.
• Parapodia are found in aquatic creatures, such as Neries, which help in swimming.
• A closed circulation system is found in them.
• These emissions are caused by renal or nephridia.
• Anelida’s body is similar to the tube inside the hose.
• In the nervous system, a nervous ring near the front end is connected to it and spreads over the length of the body. It contains interconnected nerve cords.
• Sexual methods reproduce them.
• Examples – Nereis, Fetima (Earthworm), and Herudinaria (leech).

Phylum Arthropoda

Main characteristics of Phylum Arthropoda

• Arthropoda, artho means joints, and poda means legs. This means animals whose feet are jointed are placed in the arthropods. Such animals are called Arthropods.
• This creature is the largest phylum in the kingdom. The insect has been included in this phylum.
• About 65% of all castes found on this earth are arthropods.
• They get the physical organization of the organ system level.
• Their body is divided into sections.
• They get biradial symmetry, they are triploblastic, and the true CoelomCoelom is found in them.
• Their skeleton is made of chitin, and their appendages are joined together.
• Their body is divided into the head, thoracic, and abdomen.
• Respiratory activity is done through the body’s surface, clome, respiratory tubes, and book lungs.
• An open circulation system is found in them.
• They consist of antennae, simple eye, compound eye, chemical reception, and touching sensory organs.
• Malpigian ducts are found to be excretory in them.
• They are mostly unisexual and mostly eggs.
• Financially important insects – Apis (bee), bombyx (silk insect), and Lasipher (lac insect).
• Disease carrier insect – female anopheles mosquito (malaria), culex mosquito (filaria), Aedes mosquito (chikungunya, dengue).

Phylum Mollusca

Main characteristics of phylum Mollusca

• This is the second-largest phylum.
• They are both terrestrial and aquatic.
• They have organ system level organization.
• It is a bilateral symmetry, triploblastic, and coelomic animal.
• These animals have soft bodies, but their bodies are covered with rigid calcium armor.
• Their body is made of a head, muscular foot, and a visceral mass.
• A soft spongy layer of the skin is formed on top of the hump. This is the creation of a furor.
• A fabric cavity is found between the hump and mantle, in which clome are found similar to feathers which help both respiratory and emissions.
• Sensory tactile is found on their head. Those who receive sensations.
• They have an organ called a radula to grind the food in their mouth.
• They have separate males and females, and these animals are oviparous.
• Examples – Pila (snail), Pincatada (free oyster), Sepia (Cuttlefish), Lolio (squid), Aplysia (sea rabbit), octopus (Betal fish), dentalium, etc.

Phylum Echinodermata

Main characteristics of Phylum Echinodermata

• These are called Echinodermata because the creatures of this phylum have a skeleton containing calcium, and their skin is found on the spicules.
• All these creatures are in the sea.
• In this, organ system level organization is also found.
• These are triploblastic and coelomic.
• Their larvae have bilateral symmetry, while radial symmetry is found in the adult state.
• Digestion is complete in them, and the mouth is found on the lower surface and the anus on the bottom.
• It contains a water convection system that helps in movement, food, respiration, and emissions.
• The excretory system is not found in their body.
• It is monogamous.
• The fertilization is out in them.
• Examples – Esterius (Starfish), Antidone (Marine Lily), Echinus (Sea -urchin), Ophiura (brittle star), Cucumaria (Sea Crab), etc.

Phylum Hemichordata

The main characteristic of phylum hemichordate

• They were first placed in the Chordata phylum but later they have been included in Non-Chordates.
• These animals are similar to worms which are mainly found in seawater.
• It contains organ system-level organization.
• These are triploblastic, bilateral symmetry, and coelomic animals.
• Their body is cylindrical and is divided into proboscis, collar, and trunk.
• An underdeveloped structure is found in their collar region called the stomochord which is the same structure as the notochord. Due to this, they were first placed in the Chordata phylum but later it was found out that it is not the notochord, due to which they were kept in a separate phylum, which was named Hemichordata as this Chordata shows half the incomplete characters of the phylum. Hemi means – semi and Chordata means chordates.
• The circulatory system is of open type in them.
• They are in respiratory gills.
• Proboscis glands are found in their probosci’s part which helps in emissions.
• They are monogamous, and fertilization is out.
• In them, development is indirect, that is, the larvae state is found in their life, which is called Toneria larva.
• Examples – Balanoglossus and Sacoglossus, etc.

Phylum Chordata

If you want to read about Phylum Chordata, click Read More. Friends, this article was getting very long, so complete information about Chordata is given in another article.

Friends, I hope you will like the information about the animal kingdom; if you have enjoyed it, please share it with your friends so they can also benefit from it, and if this article is a mistake, please comment and tell me.

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What are the levels of organization of the human body?

The organ system levels the organization of the human body.