The graph shows how the number of antibodies changed in an individual'b1kq/e6fm4b f * rsqrhc,i h,)s blood oveq s,f,hkrb1mb/ hi*)64e frqcr time.

What is the most likely cause of the change in antibody levels at point X?

  Which human disease was the first to be eradicc*dlmj evde3d 6+.3r bated by vaccination?

  Antibodies are proteins that bind to antigens. Whicli0 o 0;c:deec/s )duhh cell expresses the genes for a0o c;sh:ild ecedu) /0ntibody production?

  Which is true for a zoonotic dis)d+2xa 4w baasease?

  Which of these does not contribute to anti9wp.;f79gyw jsnkys)vd u* .q biotic resistance?

  Which of the following statement(s) is/are true for plasma cel2bypv.tnw5+/*ssj4kio n*b) s/hoab ls?
I.  Clones of B lymphocytes
II.  Produce large numbers of antibodies
III.  Have extensive rough endoplasmic reticulum

  Which is a correct descri3;pl;60 +hdayobhzp v ption of antigens?

The graph shows the typical immpp16a sd)8o 3sa0pz8ya5dtnj une response to two doses of a vaccine.

1.State which type of molecule stimulates antibody production.
2.Distinguish between the primary and secondary responses.
3.Explain how vaccination leads to long-term immunity.

Antibodies are protein2vkf (+ 0vz-yqvu+ krps with a specific shape that are produced by B lymphocytes-fqvv2k+r+ y(p0z u vk.
Describe how antibodies defend against pathogens.

The diagram shows how the effect of growing bacteria with diffesa.q aqa2np k7h.j-ma90rt a)rent antibiotics can be investigated. A study was conducted to test the degree om9ka0aanjp).. r7a hs-qtq2af antibiotic resistance that bacteria from a hospital door handle had developed. Measurements of the zone of inhibition were taken every 3 days, for 15 days.




1.State which antibiotic is the least effective at preventing bacterial growth.
2.State two variables that must be controlled in this experiment, other than those already given.
3.(1)Identify the anomalous result from the study.
(2)Suggest how the anomalous result may have arisen.
4.Explain how natural selection can lead to antibiotic resistance in bacteria.
5.The researchers suggested that vancomycin could be used more extensively to treat bacterial infections. Discuss to what extent you agree with this.

  The diagram shows a red blood cell f1 -d jm -y5tyqkt:qb,l5wqn.with the A antigen.



Which statement explains why a blood transfusion with blood group A cannot be given to someone with blood group O?

  Which row contains a cause and consequence of antibwuek y9*65h-9 muapxb /zwzb 1a fe5.i6xa p2aiotic resistance?

  This diagram shows the interaction between a helper T-cell and a B-lo1u25uk en dqq gaf 4ba1fg;9 2qm8az)ymphocyte.

  In blood donation, an acute hemolytic transfusion*n9pd hzqh:( l reaction occurs when red blood cells are attacked by the recipient’s immune system. Which property of red b : hq*zdlnh9p(lood cells explains this response?

  Which statement is true abw30;vfjel o5 dc op:k,out B-lymphocytes in mammals?

n a classroom investigatigp;vh2wrl4n .-ng),d f h3pijon into the effects of herbal remedies on bacterial infections, students selected a range of herbal teas, marketed as possessing “Immune System Boosting” properties. Teas each contained one main ingredient, in addition to .wnh ,p-l4i)3pghvnrgd 2;jfother secondary ingredients, present in lower concentrations.
A concentrated solution of each tea was prepared and a 0.2 g mass of cotton wool was soaked in each.
A petri dish was prepared using nutrient agar gel and inoculated with a strain of Staphylococcus aureus. The masses of cotton wool were each placed on the petri dish, which was then incubated at 20
o
C for 5 days, after which the zone of inhibition for each mass of cotton wool was measured.

Swine fever is a highly contagious disease in pigs. The disease is classi 1oi3pjc9jw5 )qpl 8rxfied into two types: xo3j ) l9q p1rjcwp5i8African and classical. Classical swine fever (CSF) is caused by the classical swine fever virus (CSFV) and can be controlled by a live attenuated vaccine. This study presents the events that occurred after the intramuscular (IM) administration of a live attenuated marker vaccine, FlagT4Gv. Such a marker vaccine enables the identification of serum samples that have come from vaccinated animals rather than infected animals and therefore allows for immunological differentiation between infected and vaccinated pigs. The aim of this study was to determine how many days are needed post-vaccination before the pigs are protected against the virus. To test the pig’s immunity to the CSFV, the virulent CSFV (BICv) was introduced intranasally between 1 and 7 days after inoculation with the marker vaccine. The number of pigs that survived in each group was recorded, as was the mean time to death. One group, the mock group, was not inoculated with the marker vaccine but was exposed to the BICv.


1.Calculate the percentage increase in mean time to death between the mock group and the group that was BICv challenged 2 days post inoculation with FlagT4Gv. Show your working.
The presence of the virus was measured for a maximum of 21 days in each group of FlagT4Gv-inoculated animals, those challenged with the BICv 1 day, 2 days, 3 days, 5 days and 7 days after inoculation with FlagT4Gv as well as in the mock group. The level of BICv was recorded and the results are shown in the graph below. Numbers correspond exclusively to the presence of BICv which was determined by immunocytochemistry.



2.(1)Based on the immunocytochemical data shown in the graph, identify the concentration of BICv 7 days post-challenge with BICv for the group infected 2 days after inoculation with FlagT4Gv.
(2)Explain the cause for the difference in viral levels between the group infected 2 days after inoculation and the group infected 3 days after inoculation.
3.Suggest a reason why data is not recorded after day seven, for the mock group and the group exposed to BICv one day after inoculation.
4.Determine the number of days post FlagT4Gv inoculation after which complete protection is achieved against BICv.
5.Describe the pattern of the results shown in the graph.
In a second experiment, tonsil tissue was collected from three different groups of pigs which had undergone different treatments, shown in the table below.


The tissue was then examined using immunohistochemistry, which involves using monoclonal antibodies and fluorescent dyes to highlight any viruses present. The results from Groups 1, 2, and 3 are shown below.



6.Describe what can be seen in the tissue sections from each of the 3 groups.
7.Suggest reasons for the appearance of the tonsil tissue from both group 1 and group 3.
8.Discuss whether the data supports the hypothesis that inoculation with FlagT4Gv prevents infection with all types of swine fever.

1.Outline the importance of international cmo/dfkq 7,fqxdm0c 1gg4y 9v5ooperation in fighting infectious diseases.4qgxk0qdg, m7 c 9f 1y5dmf/ov
2.Outline the role of monoclonal antibodies in home pregnancy tests.
3.Explain the specific immune response to a pathogen in terms of antibodies and lymphocytes.