AP Biology Chapter 11,43, 48

Phagocytic cell typle that circulates in the blood, are attracted by signals from infected tissues and then engulf and destroy the infecting pathogens.

Phagocytic cell type, some migrate throughout the body, whereas others reside permanently in organs and tissues where they are likely to encounter pathogens.

Phagocytic cell that, populate tissues, such as skin, that contact the environment. They stimulate adaptive immunity against pathogens they encounter and engulf.

Proteins that provide innate defense by interfering with viral infections. Virus-infected body cells secrete these, which induce nearby uninfected cells to produce substances that inhibit viral reproduction. In this way, these limit the cell-to-cell spread of viruses in the body, helping control viral infections such as colds and influenza.

Consists of roughly 30 proteins in blood plasma. These proteins circulate in an inactive state and are activated by substances on the surface of many microbes. Activation results in a cascade of biochemical reactions that can lead to lysis of invading cells.

Short-lived cells that thake effect immediately against the antigen and any pathogens producting that antigen.

Long-lived cells that can give rise to effector cells if the same antigen encounter later in the animal's life.

The proliferation of a lymphocyte into a clone of cells in response to binding to an antigen, so called because an encounter with an antigen selects which lymphocyte will be divide to produce a clonal population of thousands of cells specific for a particular epitope.

Antibodies bound to antigens on the surface of a virus neutralize it by blocking its ability to bind to a host cell.

Binding of antibodies to antigens on the surface of bacteria promotes phagocytosis by macrophages and neutrophils.

Binding of antibodies to antigens on the surface of a foreign cell activates the complement system.