Immunity Flashcards
What are the 2 parts of immunity?
- Innate
- Adaptive/Acquired
What is innate immunity?
Immunity present at birth and is a rapid response
What is adaptive/acquired immunity?
Immunity an individual develops through exposure to pathogens and is a slower response
What does the innate immune system include?
- Barriers
- Phagocytic leucocytes
- Plasma proteins
What physical barriers include?
- Skin
- Mucous membranes
- Hair
- Coughing, sneezing and urination
How is skin a physical barrier?
- Largest organ which protects if unbroken
- Has sebaceous glands which control pH of the skin to slow bacterial growth
- Has sweat glands that have lysozymes with antibacterial properties
How is hair a physical barrier?
- Acts as a barrier to skin
- Has cilia in respiratory system, which trap bacteria
How is coughing, sneezing and urination a physical barrier?
- Physical removal of foreign material
- Have chemical barriers
Name chemical barriers
- Sweat
- Sebaceous glands
- Tears
- Saliva
- Stomach acids
- Bile
- Ear wax
- Mucous
- Urine
- Semen
- Vaginal secretions
Name a biological barrier
Commensal bacteria on the skin and gut; this can be interfered by antibiotics
Name the different white blood cells
- Neutrophil
- Eosinophil
- Basophil
- Monocyte
- Lymphocyte
What are granulocytes and which white blood cells are they?
- Neutrophil, eosinophil and basophil
- White blood cells that contain granules and chemicals that destroy invading pathogens and infected cells.
What are neutrophils?
Frontline cells that kill bacteria that degranulate releasing chemicals
What is eosinophils?
Cytotoxic cells primarily involved destroying parasitic infections and allergies; have bright red granules
What is a basophil?
Involved in destroying parasitic infections; have darker staining granules
What are agranulocytes and whcih white blood cells are these?
- Monocyte and lymphocyte
- White blood cells that contain no granules
What are monocytes
Cells that mature into macrophages and dendritic cells responsible for phagocytosis, antigen presentation and cytokine production
What are lymphocytes?
Natural killer cells in the innate immunity, which destroy cells infected by viruses by producing interferon
What are mast cells?
A cell that contains granules of histamine and heparin, which creates an inflammatory response when encountered in an antigen
What is a dendritic cell?
Cells found in tissue that detect pathogens and move to lymph nodes to mature and activate T lymphocytes
What are interferons?
Cytokines that interfere viral replication
What are the two types of adaptive/acquired immunity?
- Humoral immunity
- Cell-mediated immunity
What is humoral immunity?
Antibody production with B lymphocytes
What is cell-mediated immunity?
Immunity involving T lymphocytes
Describe phagocytosis
A phagocyte engulfs bacteria and hydrolyses it using lysozymes and then presents the pathogen’s antigens, which are complementary to the receptor of a helper T cells, which then becomes activated.
What are antibodies?
Protein molecules which bind to antigens, which are produced by B lymphocytes
What is IgG?
Antibody mostly in blood, lymph and is able to cross the placenta
What is IgA?
Antibody found in tears, milk, blood and lymph
What is IgM?
First antibody to be secreted and is found in the blood and lymph and is unable to cross the placenta
What is IgD?
An antibody found in the blood, lymph, and on B cells
What is IgE?
Found on mast cells, basophils and are involved in allergic reactions
What are B lymphocytes?
B cells produced in bone marrow, which are activated by a T helper cell so they can differentiate into plasma cells and B memory cells.
What are plasma cells?
Cells produced by B lymphocytes and produce antibodies, which neutralise the pathogen’s antigens.
What are T helper cells?
Activate B cells to produce antibodies
What are cytotoxic T cells?
Cells that destroy viruses or tumour cells
