Innate Immunity First Line of Defense

It is a specific response that develops over time.

It is an inborn, ancient protection found in all eukaryotic organisms.

It only occurs in vertebrate animals.

It exhibits memory of past infections.

Immune means having specific protection, susceptible means not immune and at risk of infection.

Immune means being exposed to a pathogen, susceptible means never exposed.

Immune means having a fever, susceptible means having no symptoms.

Immune means taking antibiotics, susceptible means not taking antibiotics.

Barrier defenses, cellular and molecular defenses, adaptive defenses

Physical barriers, chemical barriers, fever

Antibodies, white blood cells, inflammation

Vaccines, antibiotics, memory cells

It may become confused and overreact against harmless agents.

It becomes stronger and more effective.

It stops responding to pathogens.

It produces more antibodies.

Microbe-free environments lead to underdeveloped immune systems.

Normal microbiota have a direct role in immune system development.

Germ-free animals have stronger immune responses.

Microbiota are not important for immune system development.

Mechanical barrier

Chemical barrier

Physical barrier

Antibody production

Tears washing debris from eyes

Hydrochloric acid in the stomach

Mucus membranes trapping microbes

Urine flushing microbes out of the body

Stimulate antibody production

Destroy a wide spectrum of microbes

Increase mucus production

Neutralize stomach acid

They physically block pathogen entry by forming barriers on the skin.

They rapidly kill invaders by inserting themselves into target cell membranes.

They produce antibodies to neutralize pathogens.

They engulf and digest pathogens through phagocytosis.

To produce antibodies against pathogens

To line every body cavity and entrance, acting as a physical barrier

To circulate lymph throughout the body

To filter blood in the kidneys