Immune System Flashcards
Immune system definition?
Body’s defense against disease causing organisms, malfunctioning cells and foreign particles
Immunity definition?
‘Free from burden’, ability of an organism to recognize and defend itself against specific pathogens/antigens
Immune response
Third line of defense, involves production of antibodies and generation of specialized lymphocytes against specific antigens
Antigen definition?
Molecules from a foreign organism/pathogen that provide a specific immune response
Non specific defense mechanisms?
First and second line
Specific defense mechanisms?
Third line
What is part of the first line?
Skin, mucous membranes, secretion of skin/mucous membranes
What is part of the second line?
Phagocyte WBCs, antimicrobial proteins, inflammatory response
What is part of the third liine?
Lymphocytes, antibodies
What are the two divisions of the immune system?
Cell mediated response and humoral/antibody mediated response
What is cell mediated response?
First and (mostly) second line. Efforts of WBCs (phagocytes, T cells etc), but mostly T cells. Happens when pathogenic cells are identified
What is humoral response?
Third line. Controlled by antibodies
What is part of the first line?
Skin, mucus and cilia, saliva, stomach acid
Skin’s role?
Forms a shield against invaders and secretes chemicals, killing potential invaders (dead, out layer of skin is the epidermis)
Mucus and cilia role?
Foreign particles get trapped in mucus lining respiratory system, cilia sweeps mucus into the throat to cough/sneeze
Saliva role?
Contains many chemical, breaking down bacteria
Stomach acid role?
Pathogens broken down by stomach acid
What is part of the second line?
WBCs, inflammatory response
WBC’s role?
Attacks invaders within the body
- Normally circulates the bloodstream, enters tissue if invaders detected
- Phagocytes: Eat foreign particles by engulfing them (uses lysosomes)
- T cells: Recognizes infected human cells, attacks and kills them, then continues to find other cells to kill (some= natural killers)
Inflammatory response role?
Injured body cells release histamine to begin inflammatory response
- Capillaries dilate, and pyrogens (circles blood) are release to the hypothalamus (causes temperatures to rise)
- Pain receptors activate, WBCs rush to the area
What is part of the third line?
Antibodies
Antibodies’ role?
Proteins latch onto, slow down, damage, and clump foreign particles (that get past the first/second line). Triggers the release and production of antibodies, each one has a specific binding site (antigen)
What is the antibody production?
WBCs engulf and break up invading particles, showing them to T cells that identify them, and find B cells to help. They produce antibodies and find antigen to attack on a new particle
What are the five immunoglobin/antibodies and what do they do/what are their traits?
IgA- high concentration in mucous membranes
IgG- found in all body fluids (most common)
IgM- first to be made by the body to fight a new infection
IgE- allergic reaction
IgD- small amounts in blood
What is innate/genetic immunity?
Born with it, genetically determined
What is acquired immunity?
Immunity an organism develops during a lifetime
What are the types of acquired immunity?
Naturally acquired active immunity and naturally acquired passive immunity
What are the types of artificially acquired immunity?
Artificially acquired active immunity and artificially acquired passive immunity
What are naturally acquired immunities?
Obtained in the course of daily life
What are artificially acquired immunities?
Obtained via vaccine/immune serum
What is naturally acquired active immunity?
Antigens/pathogens enter the body naturally, and the body generates immune response to antigens (immunity may be life long)
What is naturally acquired passive immunity?
Antibodies pass from mother to fetus (placenta/breastfeeding), protection till the child’s immune system develops (short lived immunity, usually weeks to months)
What is artificially acquired active immunity?
Antigens are introduced via vaccines and the body generates immune response to antigens (immunity can be life long)
What is artificially acquired passive immunity?
Performed antibodies introduced into the body via injections (short lived)
List and explain (briefly) 6 nonspecific defenses
Species: Species specific disease
Mechanical: Coverings of the body, provides a barrier
Chemical: Enzymes/chemicals providing a barrier (destroys pathogens)
Phagocytes: WBCs
Fever: Elevated body temperature, iron is removed from blood (nutrients for some pathogens)
Inflammation: Happens to an injured/infected part of the body
What is another name for an antigen?
Foreign substance in a body
What are other names for nonspecific and specific
Innate immunity and immunities
