The immune system is a network of biological processes that protects an
organism against disease. It detects and responds to a wide variety of
pathogens, from viruses to parasitic worms, as well as cancer cells and
objects such as wood splinters, distinguishing them from the organism's
own healthy tissue. Many species have two major subsystems of the immune
system. The innate immune system provides a preconfigured response to
broad groups of situations and stimuli. The adaptive immune system
provides a tailored response to each stimulus by learning to recognize
molecules it has previously encountered. Both use molecules and cells to
perform their functions. Humans have sophisticated defense mechanisms,
including the ability to adapt to recognize pathogens more efficiently.
Adaptive (or acquired) immunity creates an immunological memory leading
to an enhanced response to subsequent encounters with that same
pathogen. This process of acquired immunity is the basis of vaccination.
Read more: <https://en.wikipedia.org/wiki/Immune_system>
Today's selected anniversaries:
Wars of the Roses: At the Battle of Wakefield, Lancastrian
forces destroyed the Yorkist army and killed Richard of York at Sandal
Magna in West Yorkshire, England.
The All-India Muslim League, a political party in British India
that developed into the driving force behind the creation of Pakistan as
a Muslim state on the Indian subcontinent, was founded in Dhaka.
The Arroyo Seco Parkway, one of the first freeways built in the
U.S., connecting downtown Los Angeles with Pasadena, California, was
A series of bombings occurred around Metro Manila in the
Philippines, killing 22 people and injuring around 100 others.
Wiktionary's word of the day:
(neuroscience) A rare condition in which an individual possesses a
superior autobiographical memory and is able to recall the vast majority
of personal events and experiences in life.
Wikiquote quote of the day:
Ye know who use the Crystal Ball (To peer by stealth on
Doom), The Shade that, shaping first of all, Prepares an
empty room. Then doth It pass Like breath from
glass, But, on the extorted vision bowed intent, No man
considers why It came or went.
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