b tuberculosis (bacteria) – chalara, air, fungus; the approach makes it more spraying a few areas airborne Ebola, blood, virus. likely that results from the with a product such as c chalara ash dieback (fungi) experiment can be trusted. Glo Germ™. Don't warn – airborne 2) Remind students of Students prepare culture students that you have d malaria (protists) – animal the health advice, usually dishes, to allow air to circulate done this. Towards the vectors circulated during winter, and prevent the growth of end the lesson, tell e stomach ulcers caused by of 'catch it, bin it, kill it'. anaerobic bacteria. Dishes students what you have Helicobacter (bacteria) – oral Students should work in should be kept upside down, at done and explain that transmission pairs to note down how room temperature for several this can mimic how f Ebola (virus) – body fluids the advice is meant to days. pathogens are spread keep us healthy. They by touch. Use a UV light should then consider Prepare malt agar by mixing (which comes with the what the advice would 2 g malt extract with 2 g agar product) to illuminate help with and which and 10 cm3 of hot water to not just the areas you diseases it wouldn't work make a paste. Slowly stir in sprayed, but other parts for, and why. more water to a total volume of the classroom and of 100 cm3. Heat the mixture students' hands, to in a boiling water bath to identify how far the 95 °C, then keep it molten at spray has spread. 50 °C before using standard aseptic technique to pour it Discuss with students into sterile Petri dishes and which factors could be allow to set and the agar changed to increase or surface to dry. Prepare lawn decrease the time taken plates of Saccharomyces for all to become cerevisiae on half the agar infected, and relate plates using standard aseptic their suggestions to real technique. situations. For example, This practical is not suitable for if the pathogen is not students with sensitive skin very infectious, then conditions. only a small proportion of uninfected people
b tuberculosis (bacteria) – airborne c chalara ash dieback (fungi) – airborne d malaria (protists) – animal vectors e stomach ulcers caused by Helicobacter (bacteria) – oral transmission f Ebola (virus) – body fluids chalara, air, fungus; Ebola, blood, virus. 2) Remind students of the health advice, usually circulated during winter, of 'catch it, bin it, kill it'. Students should work in pairs to note down how the advice is meant to keep us healthy. They should then consider what the advice would help with and which diseases it wouldn't work for, and why. the approach makes it more likely that results from the experiment can be trusted. Students prepare culture dishes, to allow air to circulate and prevent the growth of anaerobic bacteria. Dishes should be kept upside down, at room temperature for several days. Prepare malt agar by mixing 2 g malt extract with 2 g agar and 10 cm3 of hot water to make a paste. Slowly stir in more water to a total volume of 100 cm3. Heat the mixture in a boiling water bath to 95 °C, then keep it molten at 50 °C before using standard aseptic technique to pour it into sterile Petri dishes and allow to set and the agar surface to dry. Prepare lawn plates of Saccharomyces cerevisiae on half the agar plates using standard aseptic technique. This practical is not suitable for students with sensitive skin conditions. spraying a few areas with a product such as Glo Germ™. Don't warn students that you have done this. Towards the end the lesson, tell students what you have done and explain that this can mimic how pathogens are spread by touch. Use a UV light (which comes with the product) to illuminate not just the areas you sprayed, but other parts of the classroom and students' hands, to identify how far the spray has spread. Discuss with students which factors could be changed to increase or decrease the time taken for all to become infected, and relate their suggestions to real situations. For example, if the pathogen is not very infectious, then only a small proportion of uninfected people