11.2. Antibodies and vaccination
A subsection of Biology, 9700, through 11. Immunity
Listing 10 of 181 questions
The causative organism of measles is Morbillivirus. Young children who have not been vaccinated for measles are at highest risk of becoming ill and of developing complications associated with the disease. The genetic material of Morbillivirus is a strand of RNA. Statements A, B and C relate to the structure of RNA. State the correct term or terms to match each of statements A to C. A The names of the two purines and two pyrimidines in RNA. purines pyrimidines B The type of covalent bond between RNA nucleotides. C The pentose sugar of the RNA nucleotide. Describe how measles is transmitted. Young children with measles may develop difficulties with breathing. This is made worse if the child is continually exposed to tobacco smoke. Tobacco smoke contains harmful compounds, such as carbon monoxide. Inhaled tobacco smoke passes through the larynx (voice boand other structures in the gas exchange system to reach the alveoli. Complete to list, in the correct sequence, the main structures of the gas exchange system through which the tobacco smoke passes to reach the alveoli. larynx alveoli State the short-term effects of carbon monoxide on the cardiovascular system. Smallpox is a disease that has been eradicated with the help of a global vaccination programme. Measles has not been eradicated, even though there is a global vaccination programme. is a graph showing the estimates of number of deaths from measles globally, between 2000 and 2017, for people who have not been vaccinated. 0.0 2.0 1.5 1.0 0.5 year number of deaths from measles in millions State the trend shown in between 2000 and 2017. Suggest reasons for the trend shown in . A child with leukaemia is at high risk of developing measles even though the child has a high white blood cell count and has been vaccinated against the disease. Explain why this child is at high risk of developing measles.
9700_w21_qp_22
THEORY
2021
Paper 2, Variant 2
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is a simplified diagram of the human circulatory system. head and arms lungs R liver stomach and intestines lower body and legs kidneys Q State why the human circulatory system is described as a closed, double circulation. Identify blood vessel Q and blood vessel R, shown in . Q R Blood leaving the heart passes through valves before it enters blood vessel R. Describe the differences between the structure of blood vessel Q and the structure of blood vessel R. Do not refer to valves in your answer. Blood plasma plays an important role in the transport of molecules such as antibodies. Scientists discovered that some of the antibodies in the blood plasma of sharks have a different structure to the antibodies found in human blood plasma. shows the structure of an antibody molecule found in the blood plasma of a shark. State how the quaternary structure of a human antibody molecule differs from the quaternary structure of the shark antibody molecule shown in . Human antibodies are used in the treatment of some forms of cancer. However, the antibodies injected into the bloodstream can only reach a small percentage of the cancer cells that form the cancerous tumour. Shark antibodies are smaller than human antibodies. Scientists are researching the possibility of injecting shark antibodies into the bloodstream to treat cancerous tumours in humans. Suggest how using the smaller shark antibodies may be more effective in reaching a greater percentage of cancer cells than human antibodies and lead to greater success at treating cancer. Antibodies can also be used in the prevention of infectious diseases. Explain how injection of antibodies into the bloodstream can protect a person from disease after infection by a pathogen.
9700_w22_qp_21
THEORY
2022
Paper 2, Variant 1
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Scientists have produced structures known as virosomes, which are used in certain vaccines. Virosomes do not cause disease. is a diagram of a section through a virosome used in some vaccinations to protect against the virus which causes influenza. phospholipid bilayer glycoprotein haemagglutinin central area glycoprotein neuraminidase enzyme State the differences between the structure of a virosome and a virus. Explain how the structure of the virosome shown in suggests that the central area of the virosome is aqueous. The glycoproteins haemagglutinin and neuraminidase are found in the influenza virus and in the virosomes used in a vaccine against the influenza virus. Haemagglutinin binds to a receptor in the cell surface membrane of phagocytes. Suggest why haemagglutinin is present in virosomes used in the vaccine for influenza. Different strains of the influenza virus have formed as a result of mutations. Each strain of the virus contains the enzyme neuraminidase. Neuraminidase helps the virus to leave host cells after the virus has replicated. In each strain of the influenza virus, the primary structure of the active site of the neuraminidase enzyme remains unchanged. Suggest why the primary structure of the active site of neuraminidase remains unchanged in each strain of the influenza virus.
9700_w22_qp_21
THEORY
2022
Paper 2, Variant 1
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Questions Discovered
181