How to Navigate: A class hierarchy (ontology) allows you to retrieve
information according to categories of interest.
In the class hierarchy that follows, each line
names a single class of biological objects. The levels of indentation
indicate a subclass relationship to the class above. The numbers in parentheses indicate the number of instances of that class.
Clicking on a class will display a page containing its
instances (the biological objects that are direct children of that
class). A class page also lists the parent classes and child classes,
allowing you to navigate up and down in the hierarchy.