Class 8 Science Chapter 1 MCQ

If the field is dry for cultivation of crops, the soil preparation is done accordingly before sowing of crops. Preparation of dry soil includes adequate watering to restore the moisture content and then tilled and ploughed to allow growth of microbes and aeration. Finally, soil is turned and its crumbs are levelled and manures are mixed. The soil is ready for sowing of crops in the field.

Apart from good quality seeds, using appropriate agricultural practices are important for getting higher yield. Mustard is a rabi crop that is sown in beginning of winters (October-November) as they need low temperature and harvested at the end of winter (April-May). It actually enriches the soil. Different crops utilizes different nutrients which permits the replenishment of used nutrients. This method is also called as crop rotation.

The ginger is a modified underground stem, which is propagated vegetative by stem (rhizome) cultivation. It does not propagate by roots, leaves or seeds.

Here, all the statements are correct except option [D]. Fertilizers are the sources of water and soil pollution. Manure is an organic substance and using of it is considered better than fertilizers. Hence, your answer will be option [D].

The soil wants nutrient to grow better yield of crop production. Sometimes, manure is added to the soil before tilling. This helps in proper mixing of manure with soil. The soil is watered before sowing.

Organic manure are obtained from decomposition of plant and animal wastes that are rich in nutrients and humus. But all nutrients might not be present in a proportionate amount in it, thus will not solve the problem if soil is particularly deficient in one or more specific nutrient.

Here, all the statements are associated with seed drill. Hence, your answer will be option [D].

Fish is good for health, we get cod liver fish oil from fish, which is rich in Vitamin-D.

The process of separating the edible part of the harvested grains (crop) by loosening and removing the scaly, inedible chaff surrounding the grain. The process utilizes a machine called “combine” which is combination of harvester and a thresher.

Manure is a natural substance obtained by the decomposition of cattle dung, human waste and plant residues. It provides a lot of humus to the soil. Manure is relative less rich in plant nutrient but using this no pollution occur and it improves the soil texture also. Thus, as an organic component cattle dung is very important for the nutrients of plants.

Irrigation is the supply of water to crops at regular intervals as water or moisture is necessary for seed germination, growth and other physiological processes. Moreover, the plants readily absorb nutrients in dissolved from along with water through root hairs of roots. It does not protect crops from frost and hot air currents and manure not irrigation improves soil texture.

Conversion of dead decaying matter into ammonia and then into nitrites and nitrates by nitrifying microbes, called “Nitrification”. Conversion of air nitrogen into nitrites and nitrates by nitrogen microbes, called “Nitrogen fixation”. Conversion of nitrites and nitrates from decaying organic matter into gaseous nitrogen by denitrifying microbes, called “Denitrification”.

“Ager” meaning field or soil, “cultura” meaning cultivation. Agriculture is the cultivation of the soil. It includes growing of plant crops and rearing of animals.

Hoe is a simple tool used for removing weeds from the field and loosening of soil, it works like a blade, pulled by the animals in the field. Plough is used for tilling of soil; axe is used for cutting trees and cultivator is another tool implemented for ploughing.

Dried neem leaves are added to stored grains, so as to prevent damage from pests. Hence, your answer will be option [D].

The ploughed field may have big pieces of soil called crumbs. It is necessary to break these crumbs with a plank. The field is levelled for sowing as well as for irrigation purposes. The levelling of soil is done with the help of a leveller.

Weedicides are sprayed during the vegetative growth of weeds “before” flowering and seed formation. Rest, all the statements are correct. Hence, your answer will be option [D].

Swaminathan has been called the “Father of Green Revolution in India” for his role in introducing and further developing high-yielding varieties of wheat in India. He is the founder of the MS Swaminathan Research Foundation also.

The process of loosening and turning of soil is called tilling and ploughing. It is the first step, in preparation of soil for cultivation of crop. Ploughing is done using a plough, made of wood or iron.

The supply of water to crops at different intervals is called irrigation. Pulley system, chain pump, dhekli and rahat (Lever system) are traditional methods of irrigation whereas sprinkler system and drip irrigation are the modern methods of irrigation.

Here, all the options are correct (may include in possibilities). Hence, your answer will be option [D].

The monsoon season in India is during the months June to September. The crops grown in this season are called kharif crop, e.g. paddy, maize, cotton etc. The kharif crops sown in June are harvested towards the end of rainy seasons (October to November).

Paddy, maize, soya-bean, groundnut, cotton, etc., are kharif crops. Rabi crops are wheat, gram, pea, mustard and linseed. Thus, wheat is not associated in kharif crops. So, your answer will be option [D].

Here, all the options are associated with animal husbandry. Hence, your answer will be option [D].

Drip system is the method of irrigation which conserve water and avoids wastages as water is made to fall drop by drop at the position of roots. It is the best technique for watering fruit plants, trees and gardens. Sprinkler system is also a modern method of irrigation that efficiently uses of water in the form of sprinklers. It is useful for uneven lands, while pulley and lever systems are traditional methods of irrigation where a lot of water is wasted.