1. Mike injured his knee while playing. Examination revealed that the injured area was red, swollen, and warmer than the surroun
ding area. What does this condition indicate? an inflammation
a tumor–like growth
a hemorrhage
2. When a virus invades the body, some B cells recognize it as nonself and produce plasma cells that release a substance to kill the virus. What is this substance called?
antigen
antibody
pathogen
3. Which of the following forms blood clots?
fibrin
macrophages
thrombin
4. An antigen has invaded a mammal's body. Specific immune cells engulf and ingest it. Some of the digested pieces are displayed on the cells' bodies. What happens next?
B cells are activated and release antibodies.
T cells are activated and produce clones.
B cells withdraw the immune response as the antigen is killed.
