Immunology (Immune System Overview) Really Just the basics. Nexyt video: .\rbr\rbr\rbr\rbr Overview of the Complement System and the pathways involved and their relationship with each other. Image: .\rbr\rbr - This video gives a great overview of the cells and functions of the immune system in response to a pathogen. Both the .\rbr\rbrAn immunology tutorial for beginners. For more: Note#1: To Clarify: InnateAdaptive is NOT interchangable with PrimarySecondary .