Activity 11.3 Let us experiment to study growth of bread mould, fungus (Rhizopus). Class 9

Activity 11.3 Let us experiment to study growth of bread mould, fungus (Rhizopus). Class 9

Activity 11.3 Let us experiment

Aim: To study growth of bread mould, fungus (Rhizopus).

Materials Required: Moist slice of bread or a roti, petridish and magnifying glass.

Procedure:

1. Take a small slice of bread or a roti and lightly moisten it with a few drops of water.
2. Using a plastic box or steel dabba, Prepare a moist chamber placing a thin layer of cotton in it.
3. Moisten it with boiled water, keep the bread or roti on it and cover it with tissue paper.
4. Keep the moist chamber in a warm and dark place, away from direct sunlight.
5. Observe the bread or roti every day for any changes. Record your observations without touching it directly.
6. Record the changes after three days, you will notice enough mould grows on it.
7. Carefully take the box to the school laboratory and with the help of needle transfer onto a microscope slide.
8. Under the guidance of your teacher, add cotton blue stain—a coloured dye to help see it better.
9. Observe the mould under the microscope and draw its diagram based on your observations.
10. Compare the diagram you have drawn with Fig. and share your observations with your classmates.

Observation:

1. The bread slice will be covered by a white cutting mass due to growth of bread mould which is the mycelium of rhizopus as in fig (a).
2. After few days, it turns black, i.e., the vegetative mycelium develops into asexual sporangia as in fig (b).

Conclusion: Each sporangia contains hundred of black spores and these spores are dispersed into air to germinate on suitable substratum.