This lesson relates to new Edexcel Biology B specification, Topic 6 Lesson 1 - Microbial Techniques. The lesson illustrates what Aseptic techniques are (using a card sort) and students then summarise in their own words. It also outlines the different methods of measuring bacterial growth, counting, turbidity etc. It includes a series of exam questions and these are also embedded throughout the lesson. Contains a step by step lesson plan which can be easily adapted. A practical on aseptic techniques could be incorporated. 100 minute lesson but easily split into two separate lessons. Also contains an exam question associated with the Exponential Growth Constant as per the new specification.