Innate vs Acquired Defense Mechanisms

There are two major types of host defenses; innate and acquired.
This exercise deals with innate defense mechanisms only.




Barriers such as skin or mucus membranes
Acid pH

Cytotoxic T cells

Time required for response

Immediate — Innate host defenses are in place, ready to go, at all times.


Takes several days for the response to be generated


Non-specific — Will attack any invader.

Specific to the microorganism against which it was generated. For example, antibodies against smallpox do not protect against other diseases such as colds or polio.

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