Integumentary & Immunological Systems Flashcards
The Integumentary System
- composed of the skin, hair, and nails
- provides a physical barrier to prevent the entrance of pathogens into the body
- the skin has subaceous glands that secrete oil onto the surface of the skin to keep its pH relatively acidic, which decreases bacterial growth
- sweat is secreted from other glands and helps cool the skin by evaporative cooling
- the skin is divided into different layers (dermis and epidermis) which are connected by the basement membrane
- hair aids the skin by directing sweat and waste away from the skin, helping with evaporate cooling when the body is hot. it also traps heat to prevent the body from being too cool
- mucus secretions in the nose and aqueous secretions in the eye help prevent foreign organisms from entering the body and resist infection
The Immunological System
- plays a key role on the destruction of internal pathogens
- two major types of immunity: humoral (involves anti-body production) and cell-mediated (involves cells taht combat fungal and viral infections)
- a defense mechanism: inflammatory response when white blood cells are activated, they release chemicals such as histamine that activate the immune response
- the lymphatic system is a part of the immune system
- lymph nodes and spleen serve as reservoirs of white blood cells and filters for lymph remaining antigen-presenting cells and foreign matter
Cell-Mediated Immunity
-immune system contains several varieties of WBC or luekocytes each with a specific function
granulocytes
attracted to the site of injury
neutrophiles
often the first responders to site of inflamation. these cells are atrracted to cytokines, which attract more WBC
eosinophils
much less common and are responsible for immune responses, esp allergic and asthmatic responses. Elevated eosinophil on a CBC often indicate an allergic response or infection by a parasite
basophils (most cells)
involved in allergic responses and parasite infections and often are responsible for the release of histamine
Monocytes
large, long-lived immune cells that differentiate into macrophages and dendritic cells. The main role of macrophages is to phagocytize dead cells and pathogens. Dendritic cells are even more focused on processing antigens and presenting them to other immune cells and therefore serve as important links between the innate and adaptive immune system.
T-Lymphocytes
- become only reactive to one specific antigen
- if there’s an infection, a MHC will indicate that the corresponding T-cell should perform its function
Cytotoxic T cells (Tc)
-recognize and respond to antigens presented by MHCI complexes. These complexes come from cells infected with viruses or developing tumors and signal Tc cells to destroy those cells
T helper (Th) cells
recognize and respond to antigens presented by MHC II complexes. Activated Th cells release cytokines to stimulate the immune response causing other white blood cells to mature and attack
- T cells begin their development in the bone marrow. They travel via the bloodstream to the thymus, where they mature. Once mature, the cells are released into the lymph
- Patients with AIDS have very low levels of certain types of T cells and as a result are particularly subject to infection b/c their immune systems are weakened by this loss
B lymphocytes
- create and express antibodies that have a high affinity for the antigen expressed by the stimulating T lymphocyte
- B cells can also stimulate the formation of memory cells
- B cells begin their development int he bone marrow and maturation is completed there and do not travel to other party of the body to mature
Active Immunity
occurs as a result of an immune response. Can be due to exposure to a pathogen or antigen or vaccination
Passive Immunity
acquired by the transfer of antibodies from on individual to another
Innate Immunity
compressed of the body’s initial, generalized defenses against pathogens (anatomic features, physiologic response, phagocyte cells, and inflammation)
