Chapter 21- Immune System Flashcards
Innate Immunity
- Functional at birth
- No memory (nonspecific defense)
Adaptive Immunity
- Develops as a person ages
- Memory (specific defense)
Both types of immunities..
work together to protect the body (at the same time, not individually)
Components of innate immunity:
Species Resistance
Mechanical Barriers
Chemical Mediators
Natural Killer Cells
Phagocytes
Inflammatory Response
Fever
Pathogen
Harmful or disease-causing organism
Species Resistance
Some diseases are unable to spread to individuals of different species. Pathogens are almost always species-specific
Zoonotic
When a pathogen affects multiple species
ex: Rabies
Mechanical Barriers
- Considered the body’s 1st line of defense
- Skin- protective as long as it’s unbroken
- Mucous membranes are also protective: stomach (HCL), saliva and tears (lysozyme)
______ is an enzyme that destroys bacteria and is a part of ____ and _____
Lysozyme
Saliva and tears
Chemical Mediators
- 2nd line of defense
- Includes interferon and complement
Interferon
Antiviral substance produced by cells (toxic to viruses)
NOT virus specific
How do interferons work?
It protects neighboring unaffected cells
Complement: group of..
Group of 20 plasma proteins that circulate the blood
Examples of complement activites (summary)
- Membrane Attack Complex
- Inflammatory response (chemotaxis, histamine)
- Opsonization
Complement activity (1)
- Alters membrane chemistry and causes lysis. MEMBRANE ATTACK COMPLEX
Complement activity (2)
- Serves as chemotaxis agents during inflammation. Stimulates the release of HISTAMINES. This increases permeability of blood vessels in injured area.
Complement activity (3)
- Helps phagocytes to adhere to the pathogen (OPSONIZATION)
Opsonization can also be termed as
enhancing phagocytosis
Natural Killer Cells
Unique WBCs that police the body in the blood/lymph
Attaches themselves to the target cell and destroys the membrane (and the cell)
Natural killer cells are ___ ____
not specific
Natural killer cells secrete..
perforins (creates a hole and then everything leaks out)
Natural killer cells work well against..
viruses and cancer
Phagocytes: pathogens that get through the skin and mucosa will be confronted with phagocytes. The chief phagocytes are ____, which..
Macrophages which derive from circulating monocytes
2 types of macrophages:
Wandering macrophages- wanders through the interstitial spaces in search of invaders
Fixed macrophages- remains within organs. ex: kupffer cells in liver
Also apart of phagocytes are _____ and ______. Sometimes the phagocytes are unable to ____ to the invader and therefore cannot ingest it.
Eosinophils and neutrophils
Adhere
Inflammation- the inflammation response will:
- Keep the infection localized
- Dispose of debris and pathogens
- Set the stage for repair
- Alerts the adaptive immune response