12. Disease and immunity
A section of Biology, 5090
Listing 10 of 225 questions
Syphilis is an infectious disease transmitted by sexual contact. It is possible to test the blood of a person for the presence of antibodies produced after infection with the pathogen that causes syphilis. State each of the following: the type of pathogen that causes syphilis the component of an infected person’s blood that produces antibodies the component of an infected person’s blood that transports these antibodies. The diagram shows part of a kit for testing a sample of blood for the presence of antibodies for syphilis. coloured lines appear here drop of blood added here S C T If antibodies for syphilis are in the drop of blood added at S, a coloured line will form at the test region, T. The presence of a coloured line at the control region, C, indicates that sufficient blood has been added and that the result at the test region, T, is valid. If a person believes that they may have been infected with syphilis, a doctor may suggest that they have a blood test. Suggest why it is advisable for a person to wait until some time after their last sexual contact has taken place before the test is carried out. Three possible outcomes of the test are shown below. coloured line C T S C T S C T S outcome X outcome Y outcome Z Complete the table below by entering either the word yes or the word no in each box to summarise the significance of each outcome. outcome is the result of the test valid? can it be concluded that the person is infected with syphilis? X Y Z State one first symptom shown by a person with primary stage syphilis. State the type of drug that should be given to a person with primary stage syphilis to prevent the disease from progressing to the secondary stage. The graph shows the number of reported cases of syphilis in men in a country between 1995 and 2012. 1995 1996 1997 1998 1999 2000 2001 2002 2003 year number of reported cases of syphilis per 100 000 population 2004 2005 2006 2007 2008 2009 2010 2011 2012 Calculate the percentage increase in the number of reported cases of syphilis in men between 2004 and 2012. Show your working. % Suggest why the actual increase in the number of cases of syphilis in men may have been higher than shown in the graph. Suggest two recommendations that may be made to men in order to reduce the number of new cases of infection with syphilis.
5090_w19_qp_22
THEORY
2019
Paper 2, Variant 2
View
Questions Discovered
225