SB5

• when a pathogen enters the body for the first time, why is the response slow?

  there aren't many B-lymphocytes that can make the antibody needed to lock onto the antigen.
• how does the body overcome infection?

  eventually the body will produce enough of the right antibody.
• what is the purpose of memory lymphocytes?

  they are produced in response to a foreign antigen, they remain in the body for a long time and remember the specific antigen.
• what does it mean if a person is immune to a disease?

  their body's immune system has the ability to respond quickly to a second infection.
• what is the secondary immune response?

  faster and stronger, often gets rid of the pathogen before you begin to show any symptoms.
• what is immunisation?

  usually involves injecting dead/inactive pathogens into the body. These are antigenic. They are harmless to your body, they make antibodies to destroy them.
• what happens if live pathogens of the same type as the immunisation get into the body?

  there will already be memory lymphocytes that can cause a secondary immune response meaning you're less likely to get a disease.
• what are the disadvantages of immunisation?

  doesn't always work/sometimes doesn't give immunity and you may have a bad reaction (swelling, fever, seizures)
• what are the advantages of immunisation?

  some diseases (smallpox) have been wiped out by immunisation programmes; herd immunisation, fewer people to pass on the disease.
• what are monoclonal antibodies produced by?

  lots of clones of a single B-lymphocyte. Meaning all the antibodies are identical and will only target 1 specific antigen.
• what is a hybridoma cell?

  fusing a mouse B-lymphocyte with a type of tumour cell called a myeloma cell to create a cell called hybridoma.
• what are the 2 things that make a hybridoma cell and why?

  lymphocytes (don't divide very easily) and tumour cells (don't produce antibodies but divide a lot).
• what is the purpose of a hybridoma cell?

  can be clones to get lots of identical cells that all divide quickly to produce the same antibodies (monoclonal). These can be collected and purified.
• why are monoclonal antibodies useful?

  they will only bind to 1 molecule, meaning you can use them to target a specific cell or chemical in the body.
• how do pregnancy sticks detect a pregnancy?

  a hormone (HCG) is found in the urine of pregnant women, which is detected by the stick.
• what is the part of the stick that you wee on?

  some antibodies stick to the hormone with blue beads attatched.
• what happens if you're pregnant and you take a test?

  the hormone binds to the antibodies on the blue beads.
• what happens second if you're pregnant and you take a test?

  the urine moves up the stick, carrying the hormone and the beads.
• what happens third if you're pregnant and you take a test?

  the beads and the hormones bind to antibodies on the strip
• what happens fourth if you're pregnant and you take a test?

  so the blue beads get stuck on the strip, turning it blue.
• what are tumour markers?

  cancer cells have proteins on their cell membranes that aren't found on normal body cells.
• how can monoclonal antibodies diagnose and treat cancer?


  in the lab, you can make monoclonal antibodies that will bind to tumour markers.
• what are antibodies labelled with to help diagnose cancer?


  radioactive element, the labelled antibodies are given to the patient through a drip. They go into the blood and are carried around the body.
• what happens when antibodies come into contact with cancer cells?

  they bind to tumour markers.
• how can doctor's see exactly where the cancer is in terms of monoclonal antibodies?

  a picture of the patient's body is taken using a special camera that detects radioactivity. Anywhere there are cancer cells will show up as a bright spot.
• when treating cancer, what is attatched to the monoclonal antibodies?

  an anti-cancer drug, given to the patient through a drip.
• what is the purpose of monoclonal antibodies in the treatment of cancer?

  the antibodies target specific cells (the cancer cells) because they bind only to the tumour markers.
• what is the purpose of anti-cancer drugs in the treatment of cancer?

  the drug kills the cancer cells but doesn't kill any normal body cells near the tumour.
• why is using monoclonal antibodies better than alternative treatments for cancer, and what are they?

  (drugs and radiotherapy) can affect normal body cells near the tumour so the side effects of antibody based drugs are lower.
• what happens when blood clots?

  proteins in the blood join together to form a solid mesh.
• how are monoclonal antibodies used to find blood clots?

  attatch a radioactive element, inject into the body and take a picture using a camera that picks up radiation, the clot will be a really bright spot.
• why is using monoclonal antibodies to find clots useful?

  you can easily find a potentially harmful clot and get rid of it before it causes harm.
• how do antibodies work?

  by inhibiting processes in bacterial cells, but not in the host organisms.
• why don't antibiotics destroy viruses?

  viruses reproduce using your body cells, which makes it very difficult to develop drugs that destroy it without killing body cells.
• what is the 1st stage of preclinical testing?

  drugs are tested on human cells and tissues in the lab.
• what is the 2nd stage of preclinical testing?

  test the drug on live animals to ensure it produces the right effect, how toxic it is, and the correct dosage.
• what is the 1st stage of clinical testing?

  tested on healthy volunteers to make sure that it doesn't have any harmful side effects on a normal, healthy working body.
• what is the 2nd stage of clinical testing?

  patients are put in 2 groups, 1 group is given the new drug and the other is given a placebo, the clinical trials are double blind.
• what does a growth medium contain?

  carbohydrates, minerals, proteins, and vitamins.
• what are the growth mediums that can be used?

  nutrient broth solutions or solid agar jelly.