Kingdom: Animals
Here we start at the top of the kingdom of animals. First of all, exactly what is an animal?
NOAA
Tubeworms
living near a seafloor volcanic vent in water that is 255 degrees
C.!
Many organisms, like the
tubeworms shown to the left, seem more like plants (or even
rocks!) than animals.
The animal kingdom is amazingly diverse, and contains both some of the simplest organisms known and the most complex and intelligent organisms on the planet!
When you think of animals, you may think of some of the living things pictured below, but what, exactly, is an animal?
Animals have the following characteristics:
1) Animals are multicellular. This means that single-celled creatures, like protists and bacteria, are not animals.
2) Animal's cells are eukaryotic, meaning (most importantly) that the cells have nuclei. Also, animal's cells lack a cell wall, as opposed to the cells of plants.
3) Typically, animals are heterotrophs, meaning that they ingest other organisms for food, rather than getting their energy from sunlight or inorganic substances.
Now, think of an animal, and let's answer some questions about it:
Many animals have a nerve cord that runs from the brain in the head through a hollow tube along the back—this is called a hollow dorsal nerve cord.
Does your animal have a hollow dorsal nerve cord?
