Question

Write the procedure to grow Rhizopus in the lab. Write the observation and precations, material required.

Answer 1

Materials required:

• 5 slices of bread
• 5 transparent sealable bags
• Gloves
• mask
• Sticky labels
• marker
• Magnifying glass
• 5 - 7 cotton swabs
• Lemon juice/water/apple juice/salt/sugar (at least two of these items are required)

Procedure:

1. We take the cotton swabs and run them over areas which have dust.
2. We then rub the dust from cotton swab over the first bread slice. We do the same with the other bread slices.
3. We seal the three bread slices inside three transparent sealable bags and put a sticker on the three bags, and write down using a marker on them. On the first sticker we write "Sample #1 - Dark Closet"; on second write "Sample #2 - Refrigerator", and on the third write "Sample #3 - Under Light" and we keep the first sample in a dark closet, second in a corner of the refrigerator where it doesn't get disturbed, and the third one in an area of the house which is most of the time brightly lit.
4. Now, we take the remaining two samples. Before we seal them in the bags we add either lemon juice/water/apple juice/salt/sugar. We keep these two samples in a place where they don't get disturbed.

Observations:

We observe the five bread samples every alternate day at a fixed time of the day (say 2 pm). It is important that we observe them every alternate day without fail, and note down the observations in a table. The observations can be their physical appearance like colour, shape, amount of growth per day, texture, etc. We can also observe the mold under the magnifying glass (usually thread-like structures are seen on top of which there is a circular shape).

Precautions:

1. We should use masks and gloves for safety.
2. We should properly dispose of the bags (without opening) after the experiment is over.