answer the following questions Chapter1 5: Improvement in food resources 21.Give two advantages of apiculture. 22.Mention two advantages of using fertilizers over manure. 23. Answer the following. a) What re concentrates in animal feed? b) Name two internal parasites that cause disease in animals. 24.Explain intensive fish farming with help of one example. 25.Expalin the ways by which crop-production can be increased. 26.State three methods by which you can control growth of weeds in agricultural fields. 27.Answer the following. a) List six factors for which the variety improvements of crops is aimed at? b) Explain two advantages of mixed cropping. 28.What are the macro and micronutrients? 29.What is animalhusbandry? 30. a) Name two common sources from which fish are captured. b) Why are mussels and shell fish cultivated?
Answers
"21. Advantages of Apiculture
""Apiculture"" is the commercial production of ""honey"" by growing bees. Some of its advantages are:
a) Bee-keeping is a low investment process and thus, it is useful for generating additional income.
b) Apart from honey, beeswax can be obtained from the beehives. Beeswax has a lot of commercial and medicinal value.
22. Advantages of fertilizers
The composition of fertilizers are better regulated and thus, one can know the exact composition of the nutrients being supplemented.
They are quickly absorbed by the plants and usually produce a higher yield compared to manure.
23. (a) Concentrates in Animal Feed
Animal feed concentrates are those components which are ""low"" in ""fibre"" but high in ""proteins"", and ""other nutrients"".
(b) Internal Parasites in Animals
Internal parasites are those which are found inside the organs of animals such as worms in the stomach and flukes in the liver.
24. Intensive Fish Farming
Intensive fish farming refers to the commercial production of fish by growing them in high stock densities. In such farming conditions, the fish are dependent solely on the food provided by the farmer and the water has to be changed continuously to remove wastes and provide proper oxygen levels to the fishes. In Europe, Rainbow trouts are usually intensively farmed in both brackish and fresh water.
25. Ways to Increase Crop Production
Crop production can be increased by the following ways:
By using manures and fertilizers to improve the ""fertility of the soil"". This will result in better nutrient availability for the plants.
By adopting proper and adequate irrigation practices depending on the crop being cultivated.
By adopting different cropping practices such as mixed cropping, inter-cropping, and crop rotation.
By using high yield variety of seeds.
26. Weed Control in Agricultural Fields
Growth of weed in agricultural fields can be controlled by implementing one or more of the following methods:
Mechanical removal of weeds
Proper preparation of seed beds and timely sowing of seeds
Adopting crop rotation practices and
Spraying of herbicides.
27. (a) Factors at which Crop Variety is aimed at
Crop variety is done so that one or more of the following factors can be achieved:
Higher yield variety can be identified.
Improved quality of crops such as baking quality in wheat and oil quality in oil seed can be obtained.
Higher resistant strains can be identified.
Shorter maturity duration strains can be obtained.
Strains which are more flexible to environmental conditions can be developed.
Crops with desirable agronomic characters can be identified.
(b) Advantages of Mixed Cropping
a) Mixed cropping helps reduce failure rates as at least one of the crops will mature and give economic returns.
b) It also ensures that soil nutrients are used as much as possible.
28. Macro and Micro nutrients
Macro nutrients are those elements which are required in large quantities by the plants for their growth and survival. There are nine macro nutrients and are Carbon, Oxygen, Hydrogen, Nitrogen, Sulphur, Phosphorous, Magnesium, Calcium, and Potassium.
Micro nutrients are those elements which are required in trace quantities by the plants for their growth and survival. There are seven micro nutrients and are Iron, Chlorine, Manganese, Zinc, Copper, Boron, and Molybdenum.
29. Animal Husbandry
Animal husbandry is the branch of science that deals with managing animal livestock. It includes various areas such as feeding, breeding, and disease control.
(a) Sources for Capturing Fish
Fishes are generally captured from the following sources:
Freshwater sources such as rivers and ponds.
Brackish water sources such as estuaries and lagoons.
Seawater sources such as seas and oceans.
(b) Reason for Cultivation of Mussels and Shell Fish
As mussels and shell fish are generally found near the sea bed, it is much more expensive to naturally harvest them compared to growing them in maricultures. Thus, for better economic returns and higher yields, mussels and shell fish are cultivated."