immune system Flashcards
what is Innate Immunity
Also called natural immunity.
Non-specific defense mechanism.
Initial response of the body to eliminate microbes and prevent infection
Fast response (minutes to hours)
examples of Physical & Chemical Barriers
Skin, hair, cilia
Mucus membranes
Tears
Mucus and chemical secretions
Digestive enzymes in mouth
Stomach acid
Blood brain barrier
what are Natural killer (NK) cells
Eliminate infected or abnormal hostcells
what are Dendritic cells
Direct microbicidal activity
Secrete chemicals that can recruit and activate other immune cells
Dendritic cells present antigen to T cells to trigger a response or antigen
what happens during inflammation
When physical barriers are breached, or infection occurs, innate immunity triggers inflammatory responses
Helps eliminate pathogens andpromotes tissue repair
Release of signalling molecules, including cytokines and chemokines
Recruits immune cells to the site of infection
Associated with heat, pain redness and swelling
what is The Complement System
Over 30 different plasma proteins
Produced in the liver but circulating in the blood
Help destroy pathogens
Immune cell activation
Clearance of immune complexes
Activated through different pathways
Bridge between innate and adaptive immunity
what is the 2 branches of adaptive immunity
cellular immunity
humoral immunity
what is Adaptive Immunity
Also called acquired immunity
Specific and targeted defense mechanism
Initiated when innate response fails to clear pathogen
Detect specific proteins (antigens) on the pathogen
Adapts to recognize and remember specific pathogens
Provides long lasting protection
Slowresponse (days to weeks
examples of cell mediated cells
dendritic cells, cytotoxic t, helper t, regulatory t, memory t
Cytotoxic T
cells directly attack and kill infected or abnormal cells
Helper T cells
assist B cells in antibody production andactivate other immunecells
Regulatory T
cells help maintain immune balance and prevent excessive responses
Memory T
cellretains a “memory” of previously encountered pathogens, enabling a faster and more effective immune response upon re-exposure
Humoral
Involves B cells
B cells produce antibodies in response to antigens
Antibodies are proteins that neutralize pathogens, mark them for destruction by phagocytes, or trigger other immune responses
basophills
releases histamine an tother molecules involved in inflammation
