Question

Answer the following questions: (8)

1. State any four uses of microorganisms.

2. Write two points of difference between: manures and fertilizers.

3. Explain the process of harvesting.

4. What happens when –

a) dilute sulphuric acid is poured on a copper plate?

b) iron nails are placed in copper sulphate solution?​

Answer 1

1. used for making curd

used for making anti biotic

used for organic acids

making yeast

2. manure _

made naturally with animal,food and kitchen waste.

doesn't harm soil.

fertiliser _

made in factories

harms the soil and it's microorganisms.

3.

Answer 2

Answer:

1)

4 uses of microorganisms are:-

a) They help in preparation of alcohol,vinegar etc.

b) They turn the milk to curd.

c) They help in preparation of antibiotics,vaccines etc.

d) They convert atmospheric nitrogen to components of nitrogen.

2) Manure:-

a)Manure contains more humus.

b)Manure can be prepared in home.

Fertilizers:-

a) fertilizers are rich in plant nutrients

b) They are prepared in factories

3) Harvesting

It is the process of cutting a metured crops from the fields.

4)

a) When dilute sulphuric acid is poured on a copper plate, no reaction takes place due to less reactivity of copper.

b) When an iron nail is dipped in copper sulphate solution, a brown coating of copper is formed on the surface of iron and the colour of copper sulphate solution changes from blue to light green.