Question

Q’s

Post-lab questions: 1. Why did we use cow manure for this lab? 2. What was the component in the agar which selected for starch degrading bacteria? 3. What is the purpose of serial dilution? 4. What is the purpose of using a selective media? 5. What was the purpose for the nutrient agar in this lab?

Lab Background/Procedures

Answer 1

1, cow eats lot of starch but require bacteria in their guts to break down as a nutrient..The enzyme which breakdown starch, releasing energy for the organism called enzyme..These bacteria can metabolize starch produce amylase..so we use this bacteria that produce amylase.it help metabolizing starch..

2, glucose was the component in the agar which selected for starch degrading bacteria..

3, This technique used to dilute the number of quantity of bacterial cells to a countable level..when the add series of dilution in to original sample in each step,we can count the number of cells in final diluted sample and calculate the stock solution to get number of cells in it..

4, selective media helps Identify a bacteria in different ways..It contain chemicals that will allow specific bacteria to grow..This selective media allow microbes growth,it also inhibit the growth of other types,it helps culture a mixed population on a selective media inorder to isolate a particular type of microbes,which helps eliminate the microbes which they do not want..so it is selective..

5, nutrient agar plate use an inoculating loop to individually streak the colony in an X shape into the center of the stock starch plate..it helps Identify type of infection due to bacteria..