Activity 1.2 Class 7 Science

This activity belongs to Chapter 1 Nutrition in Plants class 7 science

Aim of the activity

To observe mould growth on bread.

Materials used in the activity

Bread

Water

Microscope

Procedure

We will take a piece of bread and moisten it with water. Now we keep the moist bread in a humid warm place for 2 -3 days.

Observation

After 2-3 days, we check the bread. We see fluffy patches on the bread. These patches are colonies of bread mould a fungus. The colour of patches depends on the species of fungi.

Generally, these patches are black or dark brown in colour.

When we observe these moulds under a microscope, we can see a thread-like structure called hyphae. There is a bulblike structure called sporangium which contains black spores.

Explanation

These bread moulds are a species of fungi named Rhizopus stolonifera. Mould spores are present in the air or on the bread itself. When they get moist and warm environments, they grow and spread.

Conclusion

In this activity, we observed the growth of a bread mould named Rhizopus stolonifera. The presence of mould was indicated by the appearance of fluffy patches on bread when kept in a moist warm environment.