Agricultural Science 2022 Jamb Examination

Irrigation is the artificial application of water to the soil to assist in the growth of crops, especially in areas where rainfall is insufficient. This practice ensures that plants receive adequate moisture for optimal growth. The other options do not refer to artificial watering.

Silos are vertical storage structures designed specifically for grains and other bulk agricultural products. They protect the grains from pests and moisture and allow for controlled storage conditions. Barns and cribs may store crops temporarily, but silos are specialised for grain storage. Refrigerators are not used for bulk grain storage.

Seedlings are often weak and vulnerable when first germinated, so nurseries provide a controlled environment with optimal soil, moisture, and protection. This ensures healthy growth before transplanting to the field. The other options are incorrect as they do not reflect the scientific reason for raising seedlings in nurseries.

Weeding is the process of removing unwanted plants (weeds) from cultivated land to reduce competition for nutrients, light, and water. Thinning, mulching, and supplying serve different purposes and do not involve removal of unwanted plants.

Subsistence agriculture is typically small-scale and relies on family labour, simple tools, and limited production mainly for consumption rather than sale. Requiring a large area of land is not usually a characteristic of subsistence agriculture; it is more associated with commercial farming.

Rice processing involves threshing (removing grains from stalks), winnowing (removing chaff), and sometimes parboiling to improve grain quality. Fermentation is not a part of standard rice processing and is generally used in food production or alcohol brewing.

Primary tillage refers to the initial soil preparation which loosens and turns over the soil to create a seedbed. Ploughing is the main method of primary tillage, while harrowing, stumping, and ridging are secondary operations for refining soil structure.

Climatic factors are environmental conditions like temperature, rainfall, humidity, sunlight, and wind that directly influence organisms. Rocks are part of the abiotic environment but are not climatic factors.

Polygastric animals, also called ruminants, have multiple stomach chambers for digesting fibrous plant material. Cattle, deer, and sheep are ruminants. Pigs are monogastric (single-chambered stomach) and do not have this digestive adaptation.

Autecology is the branch of ecology that focuses on the study of individual organisms and their interactions with the environment. It examines how factors like light, temperature, and resources affect the life processes of a species. The other options refer to unrelated fields: embryology is development, symbiosis is interspecies interaction, and entomology is the study of insects.