Question

Wheat dough if left in the open, after a few days, starts to emit
a foul smell and becomes unfit for use. Give reason.
NCERT Class VIII
Science - Exemplar Problems
Chapter 1. Nuitrion in Plants

Answer 1

Wheat dough if left open , after a few days , starts to emit a foul smell and becomes unfit for use because , due to moisture in air the fungus starts growing on it. And due to fungus a foul smell emits from its surface.

Answer 2

Answer:

Wheat dough possesses abundant carbohydrates in the form of starch. It  enhances the growth of yeast and other saprophytic fungus and other microbes, which utilize carbohydrate as a source of energy ( as they are chemo- organotrophs, meaning that they use organic compound as an energy source) for their growth.

Moreover, the presence of carbohydrate and moisture in the dough provides an optimal environment for various types of microbes to grow over it.

Thus, when wheat dough if left exposed, after a few days, it starts to emit

a foul smell and becomes unfit for use.