Chapter 9 - The immune System Flashcards
Immunity
The state of having sufficient recourses to resist harmful microbes from entering the body. Specific and non-specific compenents
Non-specific components
Act as either barriers or as eliminators of a wide range of pathogens
specific components
Other components of the immune system adapt themselves to each new disease encountered and are able to generate pathogen specific immunity
Pathogen
Anything that causes a disease
Non-specific immunity
Aka innate immunity - the defence system with which you were born. Ex. Cough reflex, enzymes in tears and skin oils, mucus
Specific Immunity
Adaptive or acquired immunity - is immunity that develops with exposure to various antigens. your immune system builds a defence that is specific to that antigen
APCs
Antigen-presenting cells are a group of immune cells that mediate the immune response by processing and presenting antigens for recognition by certain immune cells. APCs include dendritic cells and macrophages - they act as messengers between the innate and adaptive immune system
Messengers between innate and adaptive immune systems
Dendritic cells and macrophages
Latent period
The interval between exposure to an infectious organism or a carcinogen and the clinical appearance of disease
Lymphocytes
A type of white blood cells. There are T and B type lymphocytes
B cells
Produce antibodies.
antibodies
Attach to a specific antigen and make it easier for the immune system to destroy the antigen
T cells
Attack antigens directly and help control the immune response. They also release chemicals known as cytokines which control the entire immune response
Cytokines
Control the entire immune response. Released by T cells
Passive immunity
Is due to antibodies that are produced in a body other than your own. (Infants have antibodies transferred from mother, disappear between 6-12 months). Can be injected, provides immediate protection but not long lasting protection
Immune system memory (activated B cells and sensitized T cells)
Small doses of antigen (dead or weakened live viruses) are given to activate immune system memory. This allows your body to react quickly and efficiently to future exposure.
Antigen (Ag)
Any substance (foreign to the body) that evokes an immune response. Antigens are proteins that are found on the surface of the pathogen. Antigens are unique to that pathogen
Histamine
Released when tissues are injured by bacteria, trauma, toxins or any other cause and then the damage cells release chemicals including histamine. These chemicals cause blood vessels to leak fluid into the tissues causing swelling and attract phagocytes (that eat microorganisms and dead or damaged cells - phagocytosis. Phagocytes eventually die.
Pus
Formed from a collection of dead tissue, dead bacteria and live and dead phagocytes
Allergy
Is an exaggerated immune response to substances that are generally not harmful
Anaphylaxis
A severe, whole body reaction to a chemical that has become an allergen
Histamine
Released by tissues in different parts of the body -causes the airways to tighten and lead to other symptoms
Tonsil
Prominent oval mass of lymphoid tissue on each side of the throat
Spleen
Largest lymphoid structure; destroys worn out red blood cells; reservoir for blood (sympathetic NS - ready to release if needed)
Thymus
Ductless, butterfly-shaped gland lying behind the sternum, formed mostly of lymphatic tissue that aids in the production of T cells. After puberty, the tissue gradually degenerates
lymph nodes
Act as traps for foreign particles and contain white blood cells; get inflamed or enlarged in various conditions including infections and cancer.
