Science

Q.

In crop rotation, growing of crop plants like wheat is alternated with growing of

1. Weeds

2. Legumes

3. Fruits

4. Rice

Q.

Identify the correct sequence of events carried out in preparation of soil.

1. Watering of dry soil → Ploughing →Breaking the crumbs → Levelling of soil

2. Ploughing → Levelling of soil → Watering of dry soil → Breaking the crumbs

3. Watering of dry soil → Breaking the crumbs → Ploughing → Levelling of soil

4. Breaking the crumbs → Ploughing → Leveling of soil → Watering of dry soil

Q.

Identify the given implement:

1. Cultivator

2. Sickle

3. Plough

4. Hoe

Q.

Which of the following is not a function of plough?

1. Irrigation

2. Weeding

3. Tilling the soil

4. Adding fertilizers

Q.

What is the advantage of using green manures like legumes and clover?

1. They help to destroy the weeds in crop fields.

2. They break up compact soil.

3. They have deep roots, which help to loosen the soil

4. They absorb atmospheric nitrogen and release nitrogen to soil through roots

Q.

Find the correct match of the columns.

Element supplied by fertilizer Example of fertilizers.

(i) Nitrogen (a) Super phosphate
(ii) Phosphorus (b) Potash
(iii) Potassium (c) Urea

1. (i) - (c), (ii) - (a), (iii) - (b)

2. (i) - (a) , (ii) - (c) (iii) -(b)

3. (i) - (b), (ii) - (c), (iii) - (a)

4. (i) - (b), ii) - (a), (iii)- (c)

Q.

Which of the following has to be added to the soil after sowing seeds of a high yielding crop variety?

1. Vermi-compost

2. Fertilizer

3. Decomposer

4. Manure

Q.

Chemical fertilizers may get washed into water bodies through a process called:

1. Manuring

2. Drilling

3. Sowing

4. Leaching

Q.

How does Rhizobium act as a biological fertiliser ?

1. It provides phosphorus to the plants

2. It provides humus to the soil

3. It fixes atmospheric nitrogen and provides it to plants.

4. It provides oxygen to the roots of the soil

Q.

What is the effect of deforestation of trees on the ground water level?

1. The ground water level will increase greatly

2. The ground water level will decrease

3. The ground water level will increase slightly

4. There will not be any change in the ground water level