Question

"Day 1" and "Day 2." Start by clicking Day 1. As you click through the procedure, note the order of steps you perform. Below, arrange the steps in testing for bacteria in the proper order.

1. Put on proper safety attire (lab coat and gloves)
2. Assemble the filtering device and place the sterile filter in it
3. Remove filter paper and place on agar plate. Label the plate.
4. Place the labeled agar plates in the incubator for one day to allow bacteria colonies to grow.
5. Add 1ml of the original water sample to the centrifuge tube then mix the sample on a mixer
6. Turn on vacuum to pull diluted water sample through filter
7. Make a third, most dilute sample by adding 1 mL of the 2 nd dilution to 9 mL of sterile water, then mixing
8. Pipette the 1:1000 dilution into the filter
9. Filter the remaining two dilutions \& place the filter paper from these on two more agar plates. Label the plates.
10. Make a second, more dilute sample by adding 1 mL of the first dilution to 9 mL of sterile water, then mixing
11. Shake the collected water sample
12. Add sterile water to an empty centrifuge tube to create the first dilution

Answer 1

To test for bacteria, you need to follow these steps: put on safety attire, create dilutions of the water sample, filter the diluted samples, and place the filter papers on agar plates for incubation.

Step-by-step explanation:

1. Put on proper safety attire (lab coat and gloves)
2. Add sterile water to an empty centrifuge tube to create the first dilution
3. Add 1ml of the original water sample to the centrifuge tube then mix the sample on a mixer
4. Make a second, more dilute sample by adding 1 mL of the first dilution to 9 mL of sterile water, then mixing
5. Make a third, most dilute sample by adding 1 mL of the 2nd dilution to 9 mL of sterile water, then mixing
6. Turn on vacuum to pull diluted water sample through filter
7. Assemble the filtering device and place the sterile filter in it
8. Pipette the 1:1000 dilution into the filter
9. Filter the remaining two dilutions and place the filter paper from these on two more agar plates. Label the plates.
10. Remove filter paper and place on agar plate. Label the plate.
11. Place the labeled agar plates in the incubator for one day to allow bacteria colonies to grow.