21 Turn over 8 Skin flora include bacteria that live on the skin. Different parts of the body have different types of bacteria present. Skin flora are beneficial as they inhibit the growth of pathogenic bacteria on the skin. Skin flora compete for nutrients and space or secrete toxic chemicals. (a) The following are types of bacteria found in the female genital tract: • Escherichia coli • Klebsiella species • Lactobacillus species • Staphylococcus species. (i) Describe how these types of bacteria present in the female genital tract could be identified. (4) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... 22 (ii) The photograph shows Lactobacilli on a skin cell from the female genital tract. skin cell from the female genital tract chains of Lactobacilli { Source: © Janice Carr Content Providers (s): CDC/Dr. Mike Miller Lactobacilli metabolise glycogen into lactic acid. Explain how Lactobacilli inhibit the growth of pathogenic bacteria in the female genital tract. 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(b) Sperm cells are released into the female genital tract in seminal fluid. Seminal fluid contains fructose instead of glucose. The diagram shows the structure of fructose. O H OH H CH20H H OH CH2OH OH 23 Turn over (i) Compare and contrast the structure of fructose with the structure of glucose. 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(ii) Explain the advantages of the presence of fructose in seminal fluid. 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(Total for Question 8 = 13 marks) 24 BLANK PAGE