

Guide 9A
Defense Systems
Barriers & White Blood Cells
This guide introduces the various defenses against pathogens and parasites.
Video Overview
Watch this guide overview video; you can select the closed captioning “cc” option if you would like to see the text.
Defense Systems Guide Contents
Complete all four of these sections before taking the quiz and making your media piece.
Defense Systems Objectives
Overview & Barriers
Describe how the integumentary system, cardiovascular system, skeletal system, and lymphatic system play a role in defense; list the two non-specific innate defenses and the two specific acquired defenses; and provide examples of barriers that keep pathogens and parasites out of the body.
Inflammation
Outline each step of inflammation, including why it is an important process and the role of white blood cells; list different inflammatory diseases that have appeared throughout this course; and match different forms of visualization with the information that is being conveyed.
Cell-Mediated Immunity
Define what an antigen is and explain how it relates to defending against pathogens; describe the steps of cell-mediated immunity, including the cells that are involved in the process; and explain how HIV and the Yersinia bacteria that cause the plague negatively impact the immune response.
Antibody-Mediated Immunity
Define what an antibody is and explain how it adheres to a pathogen; outline the steps of the antibody-mediated immune response; and explain why memory B and memory T cells are important.