Animals make us laugh and smile, help us grow emotionally, provide us with companionship, and provide us with many other things. In fact, it is pretty hard to think of a single function that does not benefit animals in some way. However, what some scientists are beginning to understand is that animals have some very specific purposes in their lives that go beyond having fun or getting a foot in the door. Animals are multicellular, meaning they are made up of more than one cell that is alive at once. With few exceptions, animals breathe air, eat food, can multiply, reproduce sexually, move independently, and receive information from the environment in which they live.
People tend to think of animals as only having two basic needs: food and shelter. While this is true for all animals, it is especially true for mammals and reptiles. Mammals have teeth to chew on, need to breath air, and need to have an internal organ to secrete waste materials. All of these necessities require the right combination of cellular division and nutrient transportation through the animal’s body. The digestive system is one of the ways animals get their nutrients and keep them from getting stuck in their body.
Most animals have between one and ten cell divisions per generation, which is why they live so long. However, some species divide very slowly, up to only a few steps. This is what sets some species apart from others. For example, a cat may have up to ten cell divisions during each generation, but a sloth has only one. Sloths and other slow-growing species are susceptible to becoming extinct, because their numbers drop off too quickly.
Animals are classified as protozoa, which are non-mammalian and social (live together) animals. These categories also include both bony fishes such as conchs and barracuda, and cephalopods like squid and oyster. Protozoans are animals with a single cell nucleus. They include both aquatic and terrestrial animals. An interesting fact about this last group of animals is that all animals in this kingdom except for cephalopods are freshwater animals.
Cells are made up of protein-based molecules, while the animal body is made up of organic compounds and fat. The organelles that make up the animal body can be classified into four main parts: the epidermis (top layer), the internal organs (nervous system, reproductive system, blood cells), the nervous system, and the vascular system. Each organelle has a complete set of cell (body) structures along with a process (liver, kidney, etc.) that it carries out.
An animal cell has two parts: a proton and an electron. When the proton and electron have come together in a bond, a proton will create an atom and the electron will split into two particles – a nucleus and an antineutile peptide. The digestive system of animals is a complex network of nerves that links every other organelle to a specific cell. The digestive system is probably the most important part of the animal body. Animals use their digestive system to break down food, absorb minerals and vitamins, produce energy, transport waste material away from the body and digest their food.