Biology Project
Introduction
Animals are a diverse group of organisms that make up the kingdom known as Animalia.
They are a very familiar group of organisms and are the very kingdom of life that humans
belong to. The Five kingdom classification has Animalia also known as the animal kingdom as
one of the categories. Animals are heterotrophic and their mode of nutrition is described by
the term known as Holozoic which means ingestion of food.
Even though members of the animal kingdom are incredibly diverse, animals share common
features that distinguish them from organisms in other kingdoms. All animals are eukaryotic,
multicellular organisms, and almost all animals have specialized tissues. Most animals are
motile, at least during certain life stages. Animals require a source of food to grow and
develop. All animals are heterotrophic, ingesting living or dead organic matter. This form of
obtaining energy distinguishes them from autotrophic organisms, such as most plants, which
make their own nutrients through photosynthesis and from fungi that digest their food
externally. Animals may be carnivores, herbivores, omnivores, or parasites.
Animals are eukaryotic, multicellular, species belonging to the Kingdom Animalia. Every
animal has its own unique characteristics. They obtain their energy either by feeding on
plants or on other animals. There are millions of species which have been identified, few
share similar characteristics while others differ drastically. Animals are classified based on
their characteristics. They are eminent from algae, plants, and fungus where rigid cell walls
are absent. Some are also heterotrophic, in general, they digest their food within the
internal chambers which again distinguish them from algae and plants. Another elite
character of these species is that they are motile, except in certain life stages.
Fun fact
An animal must have several characteristics to be an animal: it has a body built of
many cells, it gets the energy necessary for life by eating other organisms, it has
the ability to move, and can sense its environment.
Main features of all animals:
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They are multicellular
Their cells contain a nucleus but no cell walls or chloroplasts
They feed on organic substances made by other living things
Structure of animal cell
Types of animals
Vertebrates
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Vertebrates possess a backbone
The vertebrates are also characterized by a muscular system consisting primarily of bilaterally
paired masses and a central nervous system partly enclosed within the backbone.
The subphylum is one of the best known of all groups of animals.
Invertebrates
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Invertebrates do not possess a backbone
One of the morphological characteristics used to classify invertebrates
is whether they have legs or not
All invertebrates with jointed legs are part of the phylum Arthropods