Immuity Flashcards
Define immunity
Protection against a particular infection or disease as the antibody levels are at a minimum level to fight an invading pathogen.
Define pathogen
A micro-organism that can cause a disease
Name some non-specific responses.
Skin Cilia and mucus membrane Platelets Eye lids/lashes/brows Tears-lysozyme Hydrochloric acid in stomach Phagocytes
Who disproved spontaneous generation?
Louis Pasteur
What is spontaneous generation?
Micro-organisms that caused contamination spontaneously appear out of nowhere.
How was spontaneous generation disproved?
1) Microbes get trapped in swan neck/s-bend as they cannot travel against gravity.
2) No microbes can enter the flask as they are trapped.
3) However, air can enter the flask
4) No decay in flask means microbes are not produced by the broth
5) Therefore spontaneous generation disproved.
6) Control - open flask ( broth becomes contaminated due to entry of microbes.
Define lymphocyte.
White blood cells produced in the bone marrow that will produce complimentary and specific antibodies when exposed to a specific antigen.
Define antibody.
A globular protein produced by a lymphocyte when exposed to a specific antigen. They are specific and complimentary to antigens.
Define antigen.
A protein chemical marker capable of stimulating the production of specific and complimentary antibodies.
How do antibodies neutralise pathogens - 3 ways?
1) Antibodies attack to antigens on pathogens, clumping the, together, so they cannot spread and are easily digested by phagocytes.
2) Antibodies bind to pathogens and immobilise, damage or destroy them.
3) Antibodies bind to the pathogens and release chemical signals to attack more phagocytes.
What are the 4 types of immunity?
Natural innate
Natural acquired
Artificial active
Artificial passive
What is natural innate immunity?
From birth, antibodies are passed from mother to baby across placenta.
What is natural acquired immunity?
Develops during life - catching disease and recoding causes the body to produce its own antibodies, although it is slow.
What is artificial active immunity?
Having a vaccination - this causes the body to produce its own antibodies.
What is artificial passive immunity?
Artificial passive - antibodies ( from another source ) are injected into the body.
Where are antibodies degraded?
The liver
What can artificial active vaccines contain?
Dead pathogens
Live pathogens treated to make them harmless
Harmless fragments of the pathogen containing antigens
Toxins produced by pathogens
Why is the secondary response more effective than primary?
Memory cells are produced in the primary response, which means there are antibodies produced faster and at a higher concentration. This is because the memory cells remember how to make the antibodies on the secondary response.
Who discovered the vaccination?
Edward Jenner
How did Jenner discover the vaccination?
1) He observed that milk maids never contracted small pox.
2) He took the pus from a pox of a milk maid with cow pox.
3) He inoculated/infected a young boy with the cow pox pus.
4) Through an open wound.
5) The boy contracted and suffered cow pox and recovered.
6) Jenner then infected the boy with the small pox virus.
7) The boy didn’t suffer from small pox - he was immune. His memory cells remembered the similar antigen.
Describe the aseptic technique.
1) The metal loop is sterilised by passing it through the Bunsen burner flame. It is then allowed to cool.
2) the lid is removed from the culture bottle and the moth of this is placed near the Bunsen flame. The sterilised look is placed in the culture bottle. Replace the lid of the culture bottle.
3) Open the lid of the Petri dish AT AN ANGLE ( to prevent the entry of unwanted bacteria ). Streak/place the loop over the agar. Seal the Petri dish with tape. Heat the loop again to kill off the remaining microbes.
4) Place the Petri dish in an incubator at 25*C ( high enough to ensure maximum growth of bacteria but ensures below body temperature to prevent the growth of pathogens that are harmful to humans )
What micro-organism produces antibiotics.
Fungus, e.g. Penicillin.
What parts are contained in the bioreactor?
Stirrer-to mix nutrients and named organism
Thermometer-to minister temperature
Water jacket-to maintain optimum temperature, as a high temp. can destroy bacteria
Sterile O2 inlet-To prevent entry of unwanted micro-organisms, and to provide O2 for micro-organism growth.
Describe the process of down streaming.
Extraction, isolation, purification and packaging of a certain substance e.g. penicillin.
