6.3/11.1 Defense Against Infectious Diseases Flashcards
Explain why antibiotics are effective against bacteria but not against viruses.
Bacteria are prokaryote.
- has different protein synthesis
- has a cell wall
- anti-bodies take advantage of difference they may block the bacteria’s protein synthesis of development of cell wall this causes a bacteria to be unable to grow and divide
- however it does not affect body cells.
- viruses use body cells as host, use of their metabolism
- Body cells do not have the same protein synthesis or do not have a cell wall because they are eukaryotes-therefore body cells and consequently viruses within them are not affected by antibiotics
Outlined the role of skin as defense against pathogens
Skin is a barrier to infection. Two primary layers: dermis which is alive cells and epidermis witch is dead cells on the outside of the dead cells
-dead cells become a barrier from pathogens because they can only enter through living tissue.
Outlined the role of mucous membranes and defense against pathogens
Mucus prevent pathogens that enter through air trachea nasal urethra vagina
- The mucous membranes secrets mucus which traps pathogens and prevents them from reaching cells that they would attack.
- Some mucous has Cilia which moves trap pathogens out.
- Also’s secretes enzymes lysozyme which chemically Damages pathogens
Outline how phagocytic leucocytes ingest pathogens in the blood and body tissues.
Leukocytes: are white blood cells they help fight pathogens and provide immunity to second time pathogens.
- Macrophage: are large white blood cells are able to change shape and surround pave pathogen through say go cytosis open about back it involves the invader] macrophage can move out of small blood cells to attack invader inside body tissue
- Macrophage recognizes by antigen brother Sal is south or not self and engulfs the not self through phagocytose us.
- Lysome organelles are used to help digest the pathogen
Distinguish between antigens and anti-bodies.
Auntie Janice: molecules on outer surface of pathogen that the immune system considers not sell they trigger an immune response.
Antibodies are produced in response to specific pathogen different from each other before because of the response from the immune system to fight a pathogen
Explain anti-body production
White blood cells called B lymphocyte fights produce antibodies. General rule each B equals one type of anti-body. Problem cells produced low number of anti-bodies compared to pathogen process: a specific antigen is identified. A specific B lymphocyte is identified it produces an anti-bodies to find it to antigen. B and identical bees clone themselves and divide by mitosis- increase number
- New antibodies circulate bloodstream & find antigen match (proteins of the pathogen)- attach binding sites to antigen
- Using mechanism, antibodies eliminate pathogen
- Some of clones antibody producing lymphocytes remain in bloodstream = immunity from 2nd infection: memory cells
Outline the affects of HIV on the immune system.
- All viruses must find a type of cell in the body that matches their own proteins in a complementary way.
- HIV in fact the helper T cells which communicate which cells to call and begins at the production and blood. -When helper T cells begin to die the communication is gone no anti-body production.
- Person no longer can fight pathogens equals aids.
- HIV has the latency. Infection occurs but cells remain alive therefore can be years before aids
Describe the process of blood clotting.
Clotting factors: protein made in liver and in blood
- when body is damaged platelets cell fragments clump at site of injury.
- injured cells release PROTHROBIN ACTIVATOR, which releases Ca2+ which turns PROTHROBIN (clotting factor) into THROMBIN
- THROMBIN changes FIBRINOGEN into FIBRIN = long thread/ mesh
- Red blood cells and white blood cells platelets get caught in thread = clot = preventing further blood loss and she is pathogens.
- Platelets reach across each other contract forcing out water= scab
Outline the principle of challenge and response, clonal selection , and memory cells
Challenge and response: immune system is challenged by a pathogen at first infection, recognize pathogen by antigens.
-cellular events are the response: macrophages, helper T cells and B cells (antibodies) fight pathogen and create an immunity to the pathogen
Clonal selection:
- the identification of leukocytes/particular B lymocyte cells which help with a specific pathogen and cell division
- immune system’s select the type of cell that will be the most useful initiates cloning of that sell by the activation of helper T cells
memory cells:
-provide long-term immunity
– must experience a pathogen (antigen) to produce cells have immunity
Define active and passive immunity
Active immunity: organism is produced by memory cells which provide long-term immunity to a pathogen.
Passive immunity: organism requires antibodies produced another organism that has memory cells [shelter for mother to fetus through placenta,breast milk, injections)
Explain antibody production
antigen stimulate immune response the production of antibodies
- pathogen invade the body and are engulfed by macrophages (recognize antigen) which causes antigen presentation; molecular pieces presented in cell of pathogen
- antigen presentation trigger helper T cells
- Helper T cells bind to antigens, which activate b lymphocytes (that have the specific antibody for the antigen)
- B lymphocytes clone and differentiate into plasma cells and memory cells
- Plasma cells produce high quantities of antibodies for the antigen - bind to antigen and eliminate pathogen
- Memory cells survive for years = long term immunity
Describe the production of monoclonal antibody’s and their use in diagnosis and treatment.
Production
Monoclonal antibody’s are here: all of the same kind
-animal typically mouse is injected with an antigen that the animal recognizes and will go through primary means response many antibodies are produced to attack the pathogen
– the spleen of the animal is harvested B cells are accessed
– the B cells need to be kept alive by fusing cancerous cells with that creating HYBRIDOMA The cells live long and pretties anti-bot bodies the high Mobuto mama is cultured in separate containers and each is tested for the presence of a specific antibody - ELISA test
-hybridoma cells are immortal if kept in right environment is = synthesizing large qualities of specific antibody for treatment
Describe the diagnostic use of monoclonal antibodies
Used to test for pregnancy
– an anti-body specific to hCG which is a hormone that the embryo produce is made in this tagged onto an indicator molecule
-when hCG is present in the year and it buys that INT H GC monoclonal antibody me and moose with the food into it which is a second group of fixed antibodies
-when buys the fixed antibodyat blue line or a color change occurs demonstrating a positive result
Describe the treatment use of monoclonal antibody’s.
Can be used for emergency treatment of rabies
– maybe virus is been touched a fatal if nonvaccinated individuals
-injecting purify quantities of antibodies affect an emergency see treatment for very serious viral infections
Splaine the principle of vaccination
Vaccinations: induced artificial active immunity by stimulating the production of memory cells
- a vaccine contains a weekend [he treat chemical cheat DNA destroyed cat her immune system but resembles the same shape] forms of the pathogen and is usually injected into the bloodstream – because a modified form of the pathogens injected in individual (doesn’t cause disease)
- shape of the pathogen (antibody) recognized sheets prime Mary and he responds resulting in the production of memory cells
- the memory cells trigger a secondary immune system is much faster and stronger the second time around
