Biology 1202B Lecture Notes - Caspase, Rna Interference, Histology

32 views3 pages
30 Apr 2012
Biology Lecture Review Notes
Lecture 10
Diseases have been around much longer than humans
Immunology study of the immune system
o Involves 3 lines of defense
Physical Barrier
Physical barrier first line of defense
o Many of the body cavities are lined with mucus membranes, which contain
environments that are hostile to pathogens
Example: acidic stomach kills most ingested bacteria and breaks down most
viruses and if any survive, they are exposed to digestive enzymes and bile in the
small intestine
Example: reproductive tract is acidic to prevent pathogen survival
o Consists of other physical barriers like skin, ear wax, eye lashes, etc.
o Once something enters the body it is much more difficult to deal with and fight
Innate Immunity
Innate immunity second line of defense
o Generalized internal chemical, physical & cellular reactions against pathogens that have
survived the 1st line of defense
o Reactions typically take a few minutes to occur
o Has no memory of previous exposure to specific pathogens and acts the same,
regardless of the pathogen
o Inflammation - creates an internal condition that inhibits or kills many pathogens
o Specialized cells engulf or kill pathogens or infected body cells
Example: macrophages, neutrophils, and complement proteins
o Involves the following steps:
A break in the skin introduces bacteria, which reproduce at the wound site
Monocytes (a type of leukocyte) enter the damaged tissue from the
bloodstream through the endothelial wall of the capillary
Once in the damaged tissue the monocyte differentiates into macrophages (big
Macrophage receptors recognize & bind to surface molecules of the pathogens
and initiate phagocytosis
Cells have receptors so we can recognize if they are from within the
body or foreign
Unlock document

This preview shows page 1 of the document.
Unlock all 3 pages and 3 million more documents.

Already have an account? Log in

Get OneClass Notes+

Unlimited access to class notes and textbook notes.

YearlyBest Value
75% OFF
$8 USD/m
$30 USD/m
You will be charged $96 USD upfront and auto renewed at the end of each cycle. You may cancel anytime under Payment Settings. For more information, see our Terms and Privacy.
Payments are encrypted using 256-bit SSL. Powered by Stripe.