1. 1
   A biotechnology company is producing monoclonal antibodies for a home pregnancy testing kit. Scientists first inject a mouse with the hormone hCG (the antigen found in the urine of pregnant women), then remove lymphocytes from the mouse's spleen. These lymphocytes are fused with tumour cells to form hybridoma cells, which are then cloned to produce a large, identical population.

   (a)

   Why are the mouse lymphocytes combined with tumour cells to form hybridoma cells?

   [1 mark]

   • AHybridoma cells combine the lymphocyte's ability to produce the specific antibody with the tumour cell's ability to divide indefinitely
   • BTumour cells remove any antibodies that do not bind to hCG before the mixture is cloned
   • CFusing with a tumour cell converts the lymphocyte into a type of white blood cell that can survive in culture
   • DTumour cells directly increase the strength of the antibody's binding to the hCG antigen

   (b)

   Which statement correctly describes a limitation of using the mouse lymphocytes alone, without fusing them to tumour cells?

   [1 mark]

   • ALymphocytes on their own produce a mixture of many different antibodies rather than one specific antibody
   • BLymphocytes on their own cannot divide indefinitely, so only a small, short-lived supply of the antibody could be produced
   • CLymphocytes on their own cannot produce any antibodies unless they are fused with another cell
   • DLymphocytes on their own only recognise antigens from bacteria, not hormones such as hCG

   (c)

   Suggest two reasons why monoclonal antibodies produced from a single hybridoma clone are more useful than a mixture of antibodies for detecting hCG accurately in a pregnancy test.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A pharmaceutical company has discovered a new antibiotic compound. Before the compound can be prescribed to patients, it must pass through several stages of testing: discovery, development, preclinical testing, and then clinical testing on human volunteers and, later, patients.

   (a)

   At which stage is the new antibiotic first tested on human cells grown in the laboratory and on live animals, rather than on humans?

   [1 mark]

   • AClinical testing on healthy volunteers
   • BDiscovery
   • CPreclinical testing
   • DClinical testing on patients

   (b)

   Why is the antibiotic tested on healthy human volunteers before it is tested on patients who have the infection it is designed to treat?

   [1 mark]

   • ATo measure how effective the antibiotic is at killing the bacteria causing the infection
   • BTo find the exact dose that will cure the infection in the shortest possible time
   • CBecause healthy volunteers are legally required to test every new drug before it is given to any patient
   • DTo check that the drug is safe and does not produce harmful side effects, without the results being complicated by the patient's existing illness

   (c)

   During clinical testing, a doctor mistakenly prescribes this new antibiotic to a patient who has a common cold, which is caused by a virus. Explain why the antibiotic will not be effective at treating the patient's cold.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A GP is assessing a patient who has a mass of 98 kg and a height of 1.75 m. The patient smokes regularly and also drinks alcohol above the recommended weekly limit. The GP explains that these lifestyle factors, together with the patient's high BMI, increase the risk of several non-communicable diseases.

   (a)

   The GP calculates the patient's Body Mass Index (BMI) using the equation BMI = mass (kg) divided by (height (m)) squared. Calculate the patient's BMI. Give your answer to one decimal place and show your working.

   [3 marks]

   (b)

   Explain how the patient's smoking and regular alcohol consumption each increase the risk of a specific non-communicable disease.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A 58-year-old patient has been diagnosed with cardiovascular disease caused by narrowing of the coronary arteries. Their doctor discusses three possible treatment options: long-term medication (such as statins), a surgical procedure to widen the artery, and lifestyle changes.

   (a)

   Evaluate the advantages and disadvantages of using long-term medication compared with a surgical procedure to treat this patient's cardiovascular disease.

   [6 marks]

   (b)

   Evaluate the advantages and disadvantages of lifestyle changes as a treatment for this patient's cardiovascular disease, and discuss why a combination of medication, surgery and lifestyle changes may be the most effective overall approach.

   [6 marks]

   Total for question 4: 12 marks

End of questions