Uses of Bacteria in our life

Q.

What are the examples of helpful bacteria?

Q.

Which microbe is used in making bread?

Q.

Yeast is used in the production of:

1. Cheese and butter

2. Soap and perfume

3. Rice and vegetables

4. Bread and beer

Q.

How do microbes affect our lives?

Q.

What will happen to ‘pooris’ and ‘unused kneaded flour’ if they are left in the open for a day or two?

Q. Why do mother add a little curd to warm milk to set curd for the next day ?

Q.

What makes the bread soft and fluffy?

1. Finely ground flour.

2. Alcohol was given off during the fermentation of sugar.

3. Carbon dioxide gas is given off during the fermentation of sugar.

4. Oxygen gas.

Q.

Why can't yeast reproduce in a cold temperature ?

Q.

Which of these following is a harmful effect of microorganisms?

1. Nitrogen fixing

2. Fermenting

3. Disease causing

4. Decomposing

Q. Yeast converts sugar into and carbon dioxide, and this process is known as.

1. alcohol
2. water
3. decomposition
4. fermentation

Q.

Give one word for the following:

Bacterium that helps in the formation of curd.

Q.

How is curd prepared? [2Marks]

Q.

Which of the following organisms is/are used in the making of cheese?

1. Lactobacillus

2. Streptococcus

3. Yeast

4. Both (a) and (b)

Q.

Does fermentation kill bacteria?

Q.

Yoghurt is produced with the help of:

1. Lactic acid bacteria

2. Rhizobium

3. Protozoans

4. Yeast

Q.

Give reasons for the following:

Only a teaspoon of curd is added to milk to make curd.

Q.

Assertion — Fermentation is the process of decomposition of sugar molecules by microorganisms to produce an acid or alcohol.
Reason - Cheese is prepared by the bacterial fermentation of milk

1. If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

2. If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.

3. If Assertion is correct but Reason is incorrect.

4. If Assertion is incorrect but Reason is correct.

Q.

The process in which yeast converts sugars into alcohol is called ___.

Q.

Is it good to eat algae?

Q. When curd is added to milk, the Lactobacillus multiplies and converts the milk into curd.

1. False
2. True

Q.

Why is most milk produced converted into milk products?

Q.

Is the process of fermentation affected by enzymes?

Q.

__ promotes the formation of curd from milk.

Q.

Yeast reproduces rapidly and produces ___ and alcohol during fermentation.

Q.

Roquefort cheese is ripened by using a

1. Fungus

2. Bacterium

3. Type of yeast

4. Cyanobacteria

Q. Why is downstream processing required?

1. All of the above
2. The output from fermenter is a broth and not the final product
3. Downstream processing reduces the percentage purity of the chemical
4. During downstream processing dead microbes get processed to release the chemical

Q. Raju is suffering from loose motions. Doctor advised him to take yoghurt or buttermilk. Why?

1. To restore lost energy.
2. To quench his thirst.
3. To restore beneficial microorganisms.
4. To activate his taste receptors.

Q. discovered the first antibiotic.

1. Alexander Fleming
2. Louis Pasteur
3. Edward Jenner

Q.

An apprentice of a baker fails to get the soft and fluffy texture of bread as his master does, in his first attempt at making bread. What could be the likely reason, considering that he baked the bread for as long as his master did?

1. The apprentice did not bake the bread at the right temperature
2. The bread dough was not made from good quality wheat
3. The bread dough did not have enough water, making it hard
4. The bread dough did not ferment properly before baking

Q. Which among the following is an antibiotic?

1. Streptomycin
2. Yeast
3. Alcohol
4. Sodium bicarbonate