| Date | May 2018 | Marks available | 8 | Reference code | 18M.2.HL.TZ2.7 |
| Level | Higher level | Paper | Paper 2 | Time zone | Time zone 2 |
| Command term | Explain | Question number | 7 | Adapted from | N/A |
Question
Although simple in structure, bacteria as a group show a wide range of diversity.
Explain the production and role of antibodies in defense against bacterial pathogens in humans.
Markscheme
a. specific immune response/antibody production as a consequence of the presence of bacterial antigens
b. macrophage / phagocyte ingests bacterial pathogen displaying bacterial antigens on surface
c. attached to major histocompatibility/MHC molecules
d. helper T cell activated by presentation of antigen on surface of macrophage
e. activated helper T cell binds to B cell specific to the antigen
f. stimulated B cell undergoes repeated mitotic/cell divisions
g. «cells enlarge and differentiate» to form clone of plasma cells
h. plasma cells produce specific antibodies
i. antibodies bind to bacteria making them easier to digest by white cells
OR
opsonization
OR
agglutination
j. (some antibodies combined with antigen) activate a complement cascade to kill bacteria directly
OWTTE.
k. some antibodies act as antitoxins / neutralize toxins / change chemical structure of toxins
l. once begun, antibody production lasts for several days until all antigens destroyed
m. memory cells remain in blood giving extended immunity
Examiners report
Syllabus sections
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18M.1.HL.TZ1.22:
Mucus traps pathogenic bacteria. Mucus also attracts viruses that attack pathogenic bacteria.
[Source: EYE OF SCIENCE/SCIENCE PHOTO LIBRARY]
What part of the immune system do these viruses resemble in their function?
A. Antigens
B. Antibodies
C. Memory cells
D. Antibiotics
- 16N.1.HL.TZ0.37: What is directly responsible for allergic symptoms, including a runny nose or itchy eyes? A....
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21N.1.HL.TZ1.37:
The diagram shows a method for the production of monoclonal antibodies.
[Source: Adenosine, March 5, 2010. A general representation of the method used to produce monoclonal antibodies. [online]
Available at: https://en.wikipedia.org/wiki/Monoclonal_antibody (CC BY-SA 3.0) https://creativecommons.org/licenses/
by-sa/3.0/deed.en [Accessed 27 March 2020]. Adapted.]What are cells P and Q?
- 16N.1.HL.TZ0.38: What is required for a skeletal muscle to exert force? A. Extensor and flexor musclesB....
- 17M.1.SL.TZ1.1: Which structure found in eukaryotes has a single membrane? A. Nucleus B. Lysosome C....
- 22M.1.HL.TZ2.37: Cetuximab is a type of monoclonal antibody used to treat cancers of the large intestine. How...
- 17M.1.HL.TZ1.37: A secondary immune response occurs when an antigen is encountered on a second occasion, due...
- 17N.1.HL.TZ0.37: What forms the basis of immunity after vaccination?
- 18M.1.HL.TZ2.37: How are monoclonal antibodies produced? A. Fusion of plasma cells with tumor cells B....
- 19N.2.HL.TZ0.1f.i: State the reason for performing the experiment in the months of May to August.
- 19N.1.HL.TZ0.37: What is a role of activated B cells? A. Secrete antibiotics in response to specific...
- 18N.1.HL.TZ0.37: When activated B cells multiply, what do they produce? A. Plasma cells B. Antigens C. ...
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21M.2.HL.TZ1.4b:
A hybridoma is a cell produced by the fusion of a plasma cell with a tumour cell. Explain the advantages of using hybridoma cells in the production of monoclonal antibodies.
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22M.2.HL.TZ1.7b:
Describe how monoclonal antibodies are produced.
- 20N.1.HL.TZ0.37: Hybridoma cells are produced in laboratories for medical diagnostics and treatments. Which...
- 19M.2.HL.TZ1.1a: Identify the week and year in which the first cases were recorded in the suburbs. Week: Year:
- 19N.2.HL.TZ0.1f.ii: Suggest possible reasons for the observed pattern of presence of antibodies in vaccinated mice.
- 19M.2.HL.TZ1.1b: Based on the graph, compare and contrast the progress of the epidemic in the suburbs and...
- 19M.2.HL.TZ1.1c: Suggest two reasons for the overall decline in the epidemic after week 51.
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21M.2.HL.TZ1.4a:
Plasma cells secrete antibodies against specific antigens. Outline how plasma cells become activated.
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21M.2.HL.TZ1.4c:
State one use of monoclonal antibodies.
- 17M.2.HL.TZ2.6c: Explain the production of antibodies.
- 19M.2.HL.TZ1.1f: Based on these data, outline the evidence that T-705 has potential to be used as a treatment...
- 19M.2.HL.TZ1.1d: Compare and contrast the data for Conakry with the data for the three suburbs.
- 19M.2.HL.TZ1.1g: Explain how vaccination can lead to the production of B cells specific to the Ebola virus.
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19M.2.HL.TZ1.1e:
Suggest reasons for the high percentage of fatal cases at Ebola treatment centres.
- 19M.2.HL.TZ1.1h: Suggest possible reasons for the difficulty of preventing or controlling a viral epidemic...
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19M.1.HL.TZ1.37:
The table shows the results of blood type tests on samples from four individuals. Which row represents an individual who can accept transfusions from people with blood type AB?
[Source: © International Baccalaureate Organization 2019]
- 19N.2.HL.TZ0.1g: Analyse the data on the state of infection of tick nymphs with B. burgdorferi in control and...
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21M.1.HL.TZ2.37:
The graph shows changes in the concentration of an antibody in the blood of an individual subjected to two separate infections at time X and time Y.
[Source: Illustration from Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/, Jun 19, 2013 OpenStax College © 1999-2021, Rice University. Except where otherwise noted, textbooks on this site are licensed under a Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).]
What distinguishes the events occurring at Y from those occurring at X?
A. The individual was infected with different pathogens at X and Y.
B. Memory B cells are involved in antibody production at Y but not at X.
C. There is no clonal selection involved.
D. There are no T lymphocytes involved.
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21N.2.HL.TZ0.8b:
Explain the production of antibodies in humans.
