Innate immune system: Difference between revisions

Revision as of 04:15, 13 November 2024

Revision as of 17:52, 22 January 2025

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==Anatomical barriers==

Anatomical barriers include the physical, chemical and biological barriers. The epithelial surfaces form a physical barrier that is impermeable to most infectious agents, acting as the first line of defense against invading organisms.<ref name="Mayer" /> [[Desquamation]] (shedding) of skin epithelium also helps remove bacteria and other infectious agents that have adhered to the epithelial surface. Lack of blood vessels, the inability of the epidermis to retain moisture, and the presence of [[sebaceous gland]]s in the dermis, produces an environment unsuitable for the survival of [[microbes]].<ref name="Mayer" /> In the gastrointestinal and [[respiratory tract]], movement due to peristalsis orand cilia, respectively, helps removewith removing infectious agents.<ref name="Mayer" /> Also, [[mucus]] traps infectious agents.<ref name="Mayer" /> [[Gut flora]] can prevent the colonization of pathogenic bacteria by secreting toxic substances or by competing with pathogenic bacteria for nutrients orand cell surface attachment sites.<ref name="Mayer" /> The flushing action of tears and saliva helps prevent infection of the eyes and mouth.<ref name="Mayer" />

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! Anatomical barrier !! Additional defense mechanisms