Pathogens are agents that disrupt the physiological operations of an organism, and are acquired through infection.

Pathogens include:
● fungi
● parasites
● prions (proteins)
● protozoa

Some colonization by other organisms is harmless or helpful. Human skin, mouths, and intestines play host to numerous commensal bacteria and fungi that cause little problem, yet our innate immune systems quickly respond to pathogen-associated molecular patterns (PAMP).

Higher photosynthetic unicellular and multicellular organisms (algae and plants) ultimately acquired chloroplasts through serial endosymbiotic transfers from Cyanobacteria to an ancestral eukaryote about 1.4 billion years ago [im]. Algae, animals, fungi, plants and protists almost certainly acquired mitochondria through serial endosymbiotic transfers [im] events between an ancestral eukaryote and Rickettsiales.

Tables  Fc receptors  Immune Cytokines  Immunoglobulins

Labels: , , , , , ,

. . . since 10/06/06