Page 05 7. In an immunoassay used to detect the presence of an antigen for a disease-causing organism (pathogen), the following samples were tested. 1 A sample from an individual thought to be infected with the pathogen. 2 A sample from an organism known to cause similar symptoms, but unrelated to the pathogen. 3 A sample from the pathogen. 4 A sample of purified water. Which row in the table identifies the purpose of each sample? Positive control Negative control Test assay A 3 4 2 B 3 2 1 C 2 4 3 D 2 3 1 8. Which of the following diagrams represents the sequence of phases involved in the cell cycle? M G2 G2 S G2 S M G2 G1 G1 G1 G1 S M S M B C D A [Turn over

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This question is part of the UK A-Level Biology syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.
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