All living things can be classified into one of five categories: animals, plants, fungi, protists, and monerans.
Cells
Plants and animals differ in many ways, but one important way is the structures inside thier cells.
Here's an activity that looks at all the "organelles" (little organs) inside each of our trillions of cells, and those that are inside plant cells.
This BrainPop video is about cell specialization. That means that there are different cells in our bodies doing different jobs. The nucleus (or "command center") of the cell tells it which job it is supposed to do. In humans, for example, skin cells have a much different job than stomach cells. And in plants, leaf cells are much different from root cells.
Animals
A living thing is an animal if it has many cells, reproduces with eggs, and cannot makes its own food. It must eat other animals or plants in order to get energy. There are millions of examples of animals! Animals are divided into 2 big categories: vertebrates, and invertebrates. Vertebrates have a backbone, invertebrates do not.
Here's an x-ray of a snake. You can see its backbone, which makes it a vertebrate.
Here are some examples of animals that don't have backbones. These are invertebrates.
