Kingdom Animalia
- All are multicellular, eukaryotic organisms.
- They do not contain cell walls and chloroplasts, so they cannot perform photosynthesis.
- They take the necessary nutrients from the environment ready, that is, heterotrophic organisms.
- They store excess nutrients as glycogen.
- Most of them are mobile organisms.
- Except for sponges, many members of this group have tissues such as epithelium, muscle, ligament and nerve.
- Its growth and development is limited.
We can examine the animal kingdom under 3 groups; Vertebrates, invertebrates and primitive chordates.
1. Invertebrates:
- Invertebrates make up the largest part of the animal kingdom, they can be also called vertebrae or spinal bones.
- Except for sponges, all of them have nerve strings that pass through the abdomen.
- They do not have a backbone, but some types have an exoskeleton that covers and supports the outer part of the body.
- They usually show radial symmetry (except worms and arthropods).
- Gill slits are not observed in the embryonic period.
- They show mostly asexual reproduction.
- Respiration can be seen through the gill, trachea or cell surface.
- Most of the species with circulatory system have open circulatory system.
We can examine invertebrates with following phyla.
a) Phylum Porifera:
c) Phylum Platyhelminthes:
- Since their bodies are thin, they exchange carbon dioxide and oxygen by diffusion with the body surface.
- Digestive systems are not developed.
- They have bilateral symmetry.
- Most of them live as parasites. In non-parasitic species, there is a single cavity that serves as mouth and anus.
- Reproductive systems have developed in parasitic species. In the structure of most, both the male and female reproductive organs coexist.
- Planaria and tapeworm are the main examples.
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| Planaria |
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| Tapeworm |
d) Phylum Nematoda:
- Their bodies are round and long, and their bodies are covered with a soft and flexible layer.
- Respiratory and excretory systems are not developed, they do this by diffusion from body surfaces.
- They have a simple nervous system.
- There are two different cavity in the form of mouth and anus.
- Some live as parasites in humans, animals and plants. Others live freely in water and moist soils. These species play an important role in the separation of substances and the cycle of substances.
- They usually reproduce sexually.
- Trichinella is an example to this group.
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| Trichinella |
e) Phylum Annelida:
- Their bodies are made up of segments.
- They live freely in fresh waters, sea and land. There are also parasitic species.
- There is closed circulation.
- In the inhabitants of the land, breathing occurs with the surface of damp skin, while those living in the water make gill breathing.
- They have specially developed structures for excretion (nephridium).
- There are nervous systems consisting of the brain and nerve cords.
- They usually reproduce sexually. While the sexes of others are separate, the female and male reproductive organs are found together in some species.
- Regeneration capabilities are high. In this way, they can reproduce asexually.
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| Earthworm |
f) Phylum Mollusca:
- Their bodies are soft and shelled.
- It has full body cavity and organ systems.
- Apart from the land snail, other mollusks live in the water and gill breathing.
- Most mollusks have a muscular foot that provides movement.
- There is bilateral symmetry.
- There are tooth-like structures in their mouths that provide the breakdown of nutrients, these structures are called radula.
- There are species that feed on herbivore, carnivorous or parasite.
- Open circulation is available, except for cuttlefish and octopus.
- They reproduce by sexual reproduction.
- Octopus, squid, snails, oysters, slug, mussels are some examples of this phylum.
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| Octopus |
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| Squid |
g) Phylum Arthropoda:
- It is the most crowded group of animals. It is the group of invertebrate animals that best adapt to land life.
- Their bodies consist of three parts: head, chest and abdomen. It has articulated organs and advanced organ systems. Their bodies are covered with chitin (exoskeleton).
- There is an open circulation. Most of them are trachea breathing and gill breathing.
- There is bilateral symmetry.
- Digestive systems have improved.
- They reproduce sexually.
The arthropod group is divided into 4 classes; crustaceans, insecta, arachnida and myriapoda.
Crustaceans:
- Their bodies are surrounded by a hard shell. These shells also serve as skeletons.
- They live in fresh water or seas, respiration takes by gills, they have two pairs of antennae.
- They are separate sexual.
- There is an open circulation.
- Shrimp, crab, lobster are examples of this group.
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| Crab |
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| Lobster |
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Insecta:
- They make trachea breathing, open circulatory system is seen, they usually live on land.
- There are exoskeletons consisting of chitin.
- Their bodies consist of three parts: head, thorax and abdomen.
- They usually have two pairs of wings and three pairs of legs.
- They have antennas on their heads.
- Evacuation occurs with malpighian tubules.
- They are separate sexual, they undergo metamorphosis.
- Bees, butterflies, grasshoppers are examples of this group
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| Butterfly |
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| Bee |
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Arachnida:
- Their bodies consist of two parts (head and abdomen), the head and chest are conjoined.
- They are generally terrestrial animals. There are also aquatic and parasitic ones.
- They have four pairs of jointed legs.
- Its breathing is trachea and book lung.
- They are separate sexual and have no antenna.
- Spider, tick, scorpion are examples of this group.
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| Scorpion |
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| Spider |
Myriapoda:
- They live on land and especially in moist soils.
- Their bodies are long and consist of two parts, the head and the body.
- There are a pair of antennas at the beginning, they make trachea breathing.
- It is divided into two groups according to the number of legs coming out of each segment. The centipede has one pair of legs on each segment, millipede has two pairs of legs.
- It has an open circulation system.
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| Centipede |
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| Millipede |
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h) Phylum Echinodermata:
- They live in the seas mostly by crawling on the ground.
- They have bodies covered with spines.
- They make gill breathing. It has a closed circulatory system.
- In some species, regeneration ability is very high. In some types of starfish, even a part that leaves the body can reconstruct the whole body.
- They reproduce sexually, often undergo metamorphosis during their development. They reproduce asexually by regeneration.
- Movement and feeding are provided by the water circulation system formed by the canal and tube feet.
- It has an open circulatory system.
- Generally, there is bilateral symmetry in embryo period and radial symmetry in adulthood.
Starfish, sea urchin, sea lily, sea cucumber are some examples of this group.
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| Starfish |
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| Sea urchin |
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| Sea cucumber |
The Original Author: Mrs. Şerife (Erden) SARICA
