| Date | November 2020 | Marks available | 1 | Reference code | 20N.1.HL.TZ0.24 |
| Level | Higher level | Paper | Paper 1 | Time zone | TZ0 / no time zone |
| Command term | Question number | 24 | Adapted from | N/A |
Question
In 1940, Florey and Chain tested penicillin on bacterial infections in eight mice, before treating a sick patient. Currently, what is the correct order for testing the effectiveness of an antibiotic or other drug?
A. Affected patients, animals, healthy people
B. Animals, healthy people, affected patients
C. Healthy people, animals, affected patients
D. Animals, affected patients, healthy people
Markscheme
B
Examiners report
The basis for this question was the Nature of Science statement in the header for sub-topic 6.3. The discrimination index was very low, suggesting that some candidates who were well-prepared were not familiar with Florey and Chain’s tests. Guidance in the program for Paper 1 states this: In paper 1 there will be at least one question that addresses NOS. Candidates should therefore be prepared for a question such as this.
Syllabus sections
- 22M.1.HL.TZ1.22: Blood clotting involves a cascade of reactions. Which statement describes the blood-clotting...
- 22M.1.HL.TZ2.19: Some strains of the pathogenic bacterium Staphylococcus aureus have developed mechanisms that...
- 22M.1.SL.TZ1.26: What is a method of transmission of HIV and its effect on the immune system?
-
19M.1.HL.TZ2.36:
The blood of two men was tested and the results are shown. Anti-D refers to the rhesus blood group. Clotting indicates that antigens associated with a particular factor or blood group are present in a blood sample.
[Source: © International Baccalaureate Organization 2019]
The man who tested positive for anti-D was then tested for ABO blood group. These results were obtained.
[Source: © International Baccalaureate Organization 2019]
What ABO blood group does the man testing positive for anti-D have?
A. A
B. B
C. AB
D. O
- 17N.1.SL.TZ0.27: What can protect the body from blood loss? A. Antibodies B. Fibrin C. Histamines D....
- 20N.1.SL.TZ0.26: What is a feature of phagocytic white blood cells? A. Stimulate blood clotting B. Found...
- 18M.1.SL.TZ2.26: The body has different defenses against infectious disease. Which cells provide non-specific...
- 17N.1.SL.TZ0.26: What is a characteristic of antigens? A. They recognize foreign substances B. They are...
- 18M.2.SL.TZ1.3c: Explain how cuts in the skin are sealed by blood clotting.
- 17M.2.HL.TZ1.6b: Outline how antibiotics offer protection from certain forms of infectious disease.
- 18M.1.SL.TZ1.26: A combination of antibiotics and bioengineered antibodies to bacterial antigens is now being...
-
18M.2.HL.TZ1.1a:
Calculate the total number of M. lucifugus flights that were recorded in the summer of 2007
-
19M.1.SL.TZ1.27:
The diagram shows the major events involved in the formation of a blood clot.
[Source: © International Baccalaureate Organization 2019]
What is Factor Y?
A. Fibrin
B. Prothrombin
C. Fibrinogen
D. Thrombin
-
18M.2.HL.TZ1.1b:
Suggest one limitation of this recording method in determining the accurate mean number of individual bats flying.
-
18M.2.HL.TZ1.1c.i:
Calculate the percentage decline in the mean number of M. lucifugus flights for 2009 when compared to 2008.
- 19N.1.SL.TZ0.27: What is non-specific immunity to disease? A. Blocking prokaryotic metabolism with...
- 17N.2.HL.TZ0.02c: State the role of plasma cells in the immune system.
-
20N.1.SL.TZ0.27:
The graph shows the results of measuring two factors in the blood of patients with HIV/AIDS.
[Source: Courtesy ACRIA.]
What do X and Y represent?
- 21M.1.HL.TZ2.22: What is the role of antibiotics produced by fungi? A. Destruction of viral particles B....
-
21M.2.SL.TZ1.1a.i:
Deduce the concentration of ZDV that would cause a 50 % reduction in root growth compared to the control.
- 19M.2.SL.TZ1.1c: Based on the mode of transmission of the Ebola virus, suggest a possible reason for the...
- 19M.2.SL.TZ1.3d: Outline the role of lymphocytes in defence against disease.
-
19M.2.SL.TZ1.1a.i:
Identify the country with the largest number of Ebola cases.
- 22M.1.HL.TZ2.25: Many blood-feeding insects inject an anticoagulant into their host in order to prevent blood...
-
17N.2.SL.TZ0.02b:
Rotavirus causes diarrhea and vomiting. Explain why viral diseases cannot be treated using antibiotics.
- 17M.1.SL.TZ2.27: The bacterium Neisseria gonorrhoeae causes infections related to the human reproductive...
- 19N.1.HL.TZ0.22: How does HIV affect the immune system adversely? A. Progressive reduction in number of...
-
16N.1.SL.TZ0.26:
Why is penicillin not used in the treatment of human immunodeficiency virus (HIV)?
A. HIV patients may be allergic to penicillin.
B. Penicillin does not affect viruses.
C. Penicillin affects helper T-cell metabolism.
D. Penicillin causes antibiotic resistance. - 17M.1.SL.TZ1.21: Cladograms can be created by comparing DNA or protein sequences. The cladogram on the left is...
- 21M.1.SL.TZ2.26: Which cells are subject to attack by HIV? A. Lymphocytes B. Erythrocytes C. Platelets D....
-
18M.2.HL.TZ1.1e:
Based on the data and your biological knowledge, suggest how the infection could lead to premature death in a bat.
-
22M.2.SL.TZ2.6c:
Explain how blood clotting occurs and the consequence for a person who has hemophilia.
- 21N.1.SL.TZ0.26: A person was infected with a pathogen and then later in life they were re-infected with the...
- 19M.2.SL.TZ1.1a.ii: Identify the country with the largest number of deaths.
-
22M.2.SL.TZ1.6c:
Explain how cells and cell components in the blood defend the body against infectious disease.
- 17M.2.SL.TZ2.5c: Some blood proteins are involved in defence against infectious disease. Explain the roles of...
-
20N.2.SL.TZ0.6c:
Explain the role of cells in the defence against infectious disease.
- 19M.2.SL.TZ1.1e: Suggest two possible reasons for the drop in the daily numbers of newly infected cases after...
- 18N.1.SL.TZ0.25: Florey and Chain’s penicillin experiments would not be compliant with current protocols on...
- 16N.1.HL.TZ0.22: In Florey and Chain’s experiment, eight mice were infected with lethal doses of Streptococcus...
- 18N.2.SL.TZ0.6c: Explain how the human body defends itself against pathogens.
-
18M.2.SL.TZ1.6c:
Many diseases are caused by bacteria and other pathogens. Explain, using examples, how other factors can lead to disease in humans.
- 17M.2.HL.TZ1.1f.ii: Suggest a reason for the greater expression of the gene for the urea transporter after an...
- 18M.1.SL.TZ2.27: Florey and Chain injected four mice with Streptococcus bacteria and then penicillin and all...
-
21M.2.SL.TZ1.1a.ii:
Identify the root length, as a percentage of the control, resulting from a ZDV concentration of .
- 21N.1.SL.TZ0.25: What occurs as a result of a cut in the skin of a finger? A. Prothrombin is transformed into...
- 19M.1.SL.TZ1.28: Which statement applies to HIV? A. HIV infects red blood cells resulting in decreased...
-
21M.2.SL.TZ2.6b:
Explain the production of antibodies when a patient is infected with the TB bacterium.
-
18M.2.HL.TZ1.1f:
Outline the relationship between date of death and the mean interval between hibernation emergence periods.
- 17M.2.SL.TZ1.1c: Estimate how much smaller drilled oysters raised in seawater at a high CO2 concentration were...
-
18M.2.HL.TZ1.1d:
Distinguish between the patterns of hibernation of the uninfected and infected bats.
-
18M.2.SL.TZ1.6b:
Explain how antibiotic resistance can evolve in bacteria, such as those causing pneumonia.
- 18N.1.SL.TZ0.26: Why are antibiotics effective in curing diseases against some pathogens but not others? I. ...
- 19M.2.SL.TZ1.1b: Analysis of the data suggests that the number of deaths from EVD is not related to the total...
-
18M.2.HL.TZ1.1i:
Using all of the data, predict the effect of WNS on bat populations.
- 19M.2.SL.TZ1.1g: District administrators combatting the 2014 Ebola epidemic in West Africa were assisted by...
- 19M.2.SL.TZ1.1f: Based on these data, outline the evidence that T-705 has potential to be used as a treatment...
- 19M.2.SL.TZ1.1d: Based on the data, compare and contrast the progress of the epidemic in Liberia and Guinea.
- 19M.2.SL.TZ1.3c: Outline the causes and consequences of blood clot formation in coronary arteries.
- 19M.2.HL.TZ2.3b: Outline the actions taken by the body to avoid infection when the skin is cut.
- 19N.2.HL.TZ0.1h: Using all the data, discuss whether inoculating mice with the antigen to B. burgdorferi could...
- 19N.2.SL.TZ0.6a: Outline how cuts in the skin are sealed to prevent blood loss.
-
18M.2.HL.TZ1.1h:
Suggest one reason, other than the interval between hibernation emergence periods, for some infected bats surviving longer than others.
-
18M.2.HL.TZ1.1c.ii:
Evaluate the conclusion that the decline in the population of M. lucifugus is due to infection by the fungus.
-
18M.2.HL.TZ1.1g:
Discuss whether the data in the graph show that there is a causal link between the date of death and the interval between hibernation emergence periods.
-
21M.2.SL.TZ1.1c:
Based on the information, suggest with a reason which of the labelled cell types will become more common in Allium root tips treated with ZDV.
-
21M.2.SL.TZ1.1d:
Allium root tips continue to show some growth even at high concentrations of NVP. Suggest a possible reason for the growth seen in root tips with 800μmol NVP.
-
21M.2.SL.TZ1.1b:
Compare and contrast the effect of ZDV and NVP on the growth of Allium roots.
