cell recognition and the immune system Flashcards

Question

Process of a primary immune response using B lymphocytes

Answer 1

Only one b cell has an antibody receptor that is specific to the shape of the antigen that has entered the body The selected b cell divides by mitosis, some of the daughter cells develop into plasma cells others into memory cells Plasma cells secrete antibodies that specifically combine with the antigen that has entered the body

Answer 2

Globular glycoproteins

Answer 3

Quaternary

Answer 4

Do not vary within a class but do vary between the classes of antibodies - constant region determines the mechanism used to destroy the pathogen

Answer 5

Change for every antibody Also where the antigen binds to the antibody

Answer 6

At the end of every variable region, composed of around 120 amino acids Varies greatly due to antibody specificity

Answer 7

Gives flexibility to the antibody molecule which allows the antigen binding site to be placed at different angles when binding Its actually disulphide bridges

Answer 8

Antibodies

Answer 9

It bonds together forming an antigen-antibody complex

Answer 10

2 - can bind to 2 at once this is called agglutination which groups lots of the pathogens together

Answer 11

Neutralises the pathogen and marks it to attract phagocytes to destroy the pathogen

Answer 12

Plasma and memory cells

Answer 13

Create an immunological memory which lasts for years and when a pathogen is reencountered, the memory cells recognise the antigen and creates a after more effective response by dividing faster into plasma cells

Answer 14

The initial B lymphocytes that divide by mitosis and become plasma cells (not the memory cells ones) Secrete lots of antibodies which bind to antigens Short lived Slow reaction

Answer 15

A suspension of antigens that are intentionally put into the body to induce artificial active immunity

Answer 16

With a weakened pathogen

Answer 17

Dead pathogen in

Answer 18

Produce long term immunity as they cause memory cells to be formed which when reencountering a pathogen produce a stronger secondary response

Answer 19

Do not cause the disease they protect against because the pathogen is killed by the primary immune response

Answer 20

Antigenic variation - there is variation in the antigen of pathogens so memory cells can’t store antibodies against it

Answer 21

Occurs when the pathogen hides from the immune system by living inside cells or when the pathogen coats their bodies in host proteins, so vaccines cannot recognise or remove the pathogen

Answer 22

Pathogens multiply slowly so the primary response can destroy Produce a longer and stronger response Unsuitable if they have a weak immune system

Answer 23

contain dead pathogens cannot cause disease do not trigger a strong or long lasting immune response some may have allergic reactions to these vaccines

Answer 24

when a sufficently large amount of the population has been vaccinated

Answer 25

those that are not vaccinated are still protected as the pathogen is unable to spread if vaccinations fall below the required level then herd immunity breaks down

Answer 26

pathogens are complex and vaccines cannot be developed for them unstable political situation - hard to get vaccine out lack of public health faci;ities too few have been vaccinatied

Answer 27

immunity aquired when an antigen enters the body triggering a specific immune response naturally aquired when exposed to normal diseases or artificially aquired through vaccines long term immunity effective

Answer 28

aquired without an immune response no antibodies produced no memory cells occurs when foetuses recieve antibodies from placenta breast milk

Answer 29

aquired without an immune response no memory cells can be a transfusion of antibodies collected from people with the tetanus vaccine

Answer 30

retrovirus - has the ability to make DNA/RNA unable to survive out of human body transmitted by the direct exchange of body fluids

Answer 31

2 RNA strands proteins protein capsid viral lipid envelope glycoproteins

Answer 32

when the virus enters blood it infests helper t cells helper t cells, inmstead of seeking out and destroying pathogens, it is now a host for the HIV viral RNA enters thee cell viral reverse transcriptase enzymes produce a DNA copy of the viral RNA DNA is inserted into the chromosomes of the cell each time the cell divides it copies the new DNA infected cells can remain normal as viral DNA is inactive

Answer 33

after a long time of hiding in t helper cells, the viral DNA becomes active takes control of the t helper more HIV are produced helper t cell dies releasing many HIV particals process repeats body can no longer fight against any infections (AIDS)

Answer 34

immediately after infection - flu like symptoms which pass number of t cells gradually reduced helper t cells play an important role in the immune system can no longer produce antibodies may be attacked by an oppurtunist disease

Answer 35

drugs at slowing the rate of virus spreading no cure

Answer 36

non living so have no metabolism for antibiotics to act on and disriupt

Answer 37

Pregnancy tests Diagnosing HIV Detecting the presence of bacteria Blood typing Distinguishing between herpes 1 and 2

Answer 38

Infect mouse with human fibrin (the protein found in blood clots) This activates the plasma cells to produce antibodies against fibrin Cells are collected in the mouse spleen Plasma cells are fused with tumour cells to form hybridomas that make anti fibrin antibodies To detect where the antibodies are binding to fibrin, radiation I attached to antibodies making them labelled radioactively Gamma ray camera detects these abnormal radiation

Answer 39

Treatment for rabies - purified antibodies are injected Treatment of diseases caused by the overproduction of B-cells - antibody binds to the cell surface receptor proteins on b cells, causing the death of cells

Answer 40

Initially the antibodies were produced by mice which triggers an immune response when put into humans We overcame this issue by genetically modifying the antibody polypeptide chains so that the amino acid sequences are now human

Answer 41

All vaccines are tested on animals - unethical Animal based substances are used in the production of vaccines

Answer 42

Small risk of unpredictable side effects Often paid to do the tests - ethical issues as people feel pressured to do them Might have had the vaccine and think it works but it actually doesn’t

Answer 43

Very small probability but some people don’t take They are still protected by herd immunity Parents refuse children to be vaccinated but this is ethically questionable

Answer 44

New mca are tested on animals before they can move onto human trials Animals produce the cells which mca use

Answer 45

Study linked autism with MMR vaccine only used 12 children - due to chance He was also working with parents who were trying to sue pharmaceutical companies so it is likely the results were fixed After the study there were measles outvbreaks and the number of children diagnosed with autism still continued to rise However diagnosis of autism increased due to better diagnosing Thus no link between MMR and Autism

Answer 46

Each clone of plasma cells produces just one type of antibody - a mca

Answer 47

HIV antigens are bound to the reaction vessel Blood plasma is taken from the patient and added to reaction vessel HIV specific antibodies will bind to the HIV antigens Any other antibodies are washed out A second antibody with an enzyme attached is added the the vessel and bind with primary Washed out to remove unbound - avoids false positives Substrate put into vessel - if there is any antibodies binding the substrate will be hydrolysed by the enzyme producing a colour

Answer 48

Same as indirect however the antibodies are bound to the bottom of the reaction vessel, an antigen will bind to this then another antibody with enzyme then substrate with washing out between each step.