The graph shows how the concentration of lactose sugar changes during the formation of yoghurt from milk over a period of 48 hours. [Figure 3.1]

1. (a)(i)Name the type of microorganism used in the production of yoghurt.[1]
2. (a)(ii)Name the type of cell division that causes the population of this microorganism to increase over the 48-hour period.[1]
3. (a)(iii)Name the acid produced by this type of microorganism in the formation of yoghurt.[1]
4. (a)(iv)Draw a line on the graph to show how the concentration of this acid will change during the 48-hour period.[2]
5. (b)(i)Lactose intolerance is a medical condition that results from a genetic change. A person with the condition is unable to produce molecules of the correct enzyme to digest lactose sugar. Name this type of genetic change and explain how it can result in a person being unable to produce molecules of the correct enzyme.[3]
6. (b)(ii)The low concentration of lactose sugar in yoghurt makes it a better food than milk for a person with lactose intolerance. Outline the health benefits to some people with lactose intolerance of continuing to include a dairy product such as yoghurt in the diet.[2]

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