Gene Ontology annotations are based on varying levels of evidence. Use the GO evidence code to what evidence these predictions are based on. If you mouse over the evidence code, it will give a description of the code. Here is a list of some common ones:
The Homology section provides links to databases that contain information about homologs of this gene.
Clone name provides the name of the DNA clone that the sequence was derived from.
The Gene Ontology section gives information about the gene's function. The information here is provided be the Gene Ontology Annotation Database at the European Bioinformatics Institute (EBI). This section is divided into Function and Process tables.
Each table has information on the Function (which links to the AMiGO 2 search of the Gene Ontology Database), an evidence code (see the side bar for more information) and links to primary literature in PubMed.
Function: the biochemical activity the gene is involved in
Process: the cellular process the gene is involved in