Question

Colonies of yeast fail to multiply in water but multiply in sugar solution. Choose one reason for this-
A) Sugar provides energy to sustaining all life activities
B) Water provides energy to sustaining all life activities
C) Sugar provides a surface for sustaining all life activities
D) all of the above

Answer 1

Hint:Every organism needs nutrients to grow and flourish. They will obtain these nutrients from their surroundings. Thus lack of nutrients in the surrounding will cease their growth. This food will only enable other metabolic activities to take place.

Complete answer:
When the colony of yeast is present in water, it does not get any nutrition. Sugar solution, on the contrary, provides nutrition. As the yeast gets nutrition and energy, it grows and multiplies which leads to producing buds. That is why colonies of yeast fail to multiply in water, but it multiplies in sugar solution.
Option A:-Yeast can use sugar as food. Several chemical changes can occur inside the bottle when there is food and energy is present. The yeast will turn the sugar to turn into alcohol, carbon dioxide, and energy. Carbon dioxide gas causes the bread to rise during baking as the bubbles push the moist dough up and outward and leads to fermentation.
Option B:-This process is sometimes known as the proofing of the yeast. It is when you add yeast to water. As the yeast is present in the water, it begins to dissolve and the yeast is activated. Once the yeast has been activated or “awakened,” it will begin to feed on the sugar in the water and further chemical action starts taking place and carbon dioxide starts coming out, which gives rise to bubbles.
Option C:-Sugar provides a surface for sustaining basic all life activities in yeasts. For growth, yeast requires nutrition and energy which they get by glucose. As the presence of glucose is there, it leads to the multiplication of the yeast and leads to the production of carbon dioxide. It is scientifically known as Saccharomyces cerevisiae.

Therefore the correct option is "D" – all of the above.

Note: While sugar and other sweeteners provide "food" for yeast, too much sugar can also damage yeast, drawing liquid from the yeast and hampering its growth. Too much sugar also slows down gluten development. So the excess of sugar levels can damage them also.