Week 1 Chapter 13 Flashcards
(42 cards)
First Line of defense: Innate Immune System/ External
includes the skin and the mucous membranes
How does skin act as a line of defense?
-act as a physical barrier
-houses resident microorganisms
-acidic pH and fatty acid content of sweat
How does the Mucous Membrane act as a line of defense?
-cilia and mucous in respiratory system
-acidity of stomach
-fluids such as tears, saliva, and urine
Second line of defense: Internal
Cellular and Chemical components:
Spleen, Lymphatic System, Red Bone Marrow
How does the spleen provide internal protection?
-white pulp has immunological functions
-phagocytic cells react to antigens in bloodstream
-macrophages in red pulp remove worn, damaged blood cells
How does the Lymphatic system help provide internal protection?
-responsible for collecting & returning excess fluid to the cardiovascular system
-lymph nodes: small structure responsible for lymph filtration as it travels back to systemic circulation
How does Red Bone Marrow help provide interal proteciton?
responsible for production of white blood cells
What are the 4 primary functions of the Lymphatic system?
- removal of excess tissue fluid
- waste material transport
- filtration of lymph
- protein transport
What is Innate (nonspecific) immunity?
rapid and destroys non-self invaders indiscriminately
What is Adaptive (acquired) immunity?
targets specific organisms and as is slower to respond to an invading organisms
Innate Immune System
-rapid, nonspecific
-present at birth
-physical barriers: skin, hair/fur, mucous membranes, cilia, mucous and chemical secretions
-destroys non self invaders: uses physical, chemical, and cellular components to protect body
Adaptive Immune System
-slower to respond
-not present at birth
-targets specific organisms
-develops and adapts as animal matures and is exposed to antigens (uses antibodies, memory cells, plasma cells, B and T lymphocytes
Examples of Internal Innate Immunity
-inflammation
-fever
-phagocytosis
-complement system
Inflammation
body’s localized rx in response to trauma, infection, chemical exposure , or excessive heat
Fever
-elevated body temp
-systemic inflammation response where chemical mediators are carried throughout
-excessively high body temperature (>104) may cause proteins to denature
Phagocytosis
-one way the body can remove pathogens from the blood, fluids, and body tissues
-neutrophils, monocytes, macrophages, dendrite cells
-5 steps: activation, attachment, ingestion, destruction, exocytosis
Complement System
-30+ plasma protein
-become active in presence of antigen or antibody attached to an antigen
-produced primarily in liver
-identified by C followed by a number
-always present in plasma in inactive form
Functions of the complement system
-trigger inflammation
-alter microbial cell membranes
What is a complement cascade?
when one complement protein is activated, it activates the next complement protein in the series
-final result is antigen cell lysis or body cell apoptosis
Cytokines
-attract immune cells to specific site
-act as inhibitor molecules
-enhance the immune process
-play a major role in hematopoiesis
-types: interleukins, interferons, chemokines
What are natural killer cells?
-found in blood and lymph
-part of both innate and adaptive immune system
-do not ingest target cell
-bind to cell to induce cellular changes leading
- 2 types of receptors on cell membranes:
Killer inhibitory receptors, Killer activating receptor
What are interferons?
-produced by animal’s immune system cells in response to presence of viruses, bacteria, cancer, and other foreign objects
-bind to membrane-bound receptors on surrounding non infected cells
-relay signal to inner portion of non infected cells to produce inactive antiviral particles (AVPs):
when virus enters cell, AVPs are activated then virus replication is inhibited in the cell
B Lymphocytes
-formed in the bone marrow
-programmed to secrete a specific antibody = immunoglobulin
-migrate to lymph nodes and spleen:
*when stimulated by presence of specific antigen
*differentiate into plasma cells
*responsible for actual production, storage, and release of antibodies
T Lymphocytes
- precursors are thymocytes that originate in red bone marrow then migrate to thymus to mature and multiply
-enter blood stream as T cells then migrate to lymph nodes and spleen, coordinate cell-mediated immunity and activate B cells
