WAEC SSCE - Agricultural Science - 2012

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Striga spp. is a parasitic weed of sorghum. It is a serious threat to sorghum production in many parts of Africa, including West Africa. The weed attaches itself to the roots of sorghum and absorbs nutrients and water from the host plant, resulting in stunted growth, reduced yield, and even crop failure. It is important for farmers to manage Striga spp. through a combination of cultural practices, such as crop rotation and intercropping, and chemical control methods, such as the use of herbicides.

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The correct answer is: I and III only. Rubber production involves coagulation, which is the process of solidifying liquid latex into a coagulated mass, and tapping, which is the process of collecting latex from the rubber tree through incisions made on the bark of the tree. Fermentation is not a process associated with rubber production, as it is used primarily in the production of some agricultural crops and beverages.

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Citrus trees are usually propagated by budding. This is a vegetative propagation method where a bud of a selected variety is inserted into the bark of a rootstock. The bud then grows into a shoot which becomes the scion and the rootstock provides the root system. The use of budding ensures that the new trees have the same characteristics as the parent tree, and also allows for the production of disease-resistant trees. It is a common and effective method of citrus propagation in commercial agriculture.

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Fruits should be harvested at the appropriate time in order to ensure good quality produce. Harvesting fruits at the right time helps to maximize their flavor, texture, and nutritional content. If fruits are harvested too early or too late, their quality can be compromised, resulting in a loss of taste, texture, and nutrient value. Therefore, it is important to carefully monitor and determine the appropriate time for fruit harvesting to obtain high-quality produce.

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A farm business makes a profit when the total revenue exceeds the total cost. This means that the income generated from selling the products or services is greater than the expenses incurred in producing them. In other words, the farm business is earning more money than it is spending. Profit is important for the sustainability and growth of a farm business, as it provides funds for reinvestment in the business, expansion, and future development.

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The crops that are useful to the soap-making industry are coconut and shea nut. Coconut oil is commonly used in soap-making due to its ability to create a rich, creamy lather and its moisturizing properties. Shea butter, which is derived from the shea nut, is also commonly used in soap-making due to its moisturizing and healing properties for the skin. Kolanut, on the other hand, is not typically used in soap-making. Therefore, the correct option is II and III only.

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Out of the given options, the only insect-pest that possesses biting and chewing mouthparts is the grasshopper. Biting and chewing mouthparts are specialized structures that enable an insect to cut, crush and grind solid food materials, such as plant tissues. Grasshoppers are known to cause significant damage to agricultural crops due to their feeding behavior. They feed on various types of plants, including grasses, cereals, vegetables, and fruits, by biting and chewing through the plant tissues.

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The statement that is true about the effects of diseases on crops is that they lead to a reduction in the quality of products (I), a reduction in the photosynthetic ability (II), and a reduction in the yield of the produce (IV). Crop diseases can cause discoloration, spots, and other blemishes that lower the market value of the crop. They can also interfere with the plant's ability to perform photosynthesis, which reduces its growth and productivity. Moreover, some diseases can cause the plant to wither or die, which ultimately reduces the yield of the crop. While diseases may not necessarily increase the cost of production (III), they can still have a significant economic impact by reducing the quantity and quality of the produce. Therefore, the correct option is I, II, and IV only.

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The type of weed control involved when tilapia feeds on aquatic weeds is biological. This is because the control method involves the use of living organisms (tilapia fish) to naturally reduce the growth and spread of aquatic weeds in a water body. The tilapia fish feed on the weeds and thereby limit their growth, without the use of any chemical or mechanical means. This method is a sustainable and environmentally friendly approach to weed control in aquatic environments.

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The botanical name of groundnut is arachis hypogaea. Botanical names are a way to identify plants using a standardized system of names, which helps to avoid confusion caused by common names that can vary from region to region or even from person to person. The botanical name of a plant consists of two parts: the genus name, which is capitalized, and the species name, which is not capitalized. In this case, "arachis" is the genus name and "hypogaea" is the species name. Knowing the botanical name of a plant can help people communicate more effectively about it, as well as provide a more accurate way to identify it.

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If an injured goat is bleeding without clotting, the goat is likely deficient in Vitamin K. Vitamin K is an important nutrient that helps the blood clot. When an injury occurs, the body needs to form a blood clot to stop the bleeding. Without enough Vitamin K, the blood will not clot properly and the bleeding will continue. This can be dangerous because the goat can lose too much blood and become very sick. Other vitamins like vitamin D, vitamin E and vitamin C are important for the body, but they don't play a direct role in blood clotting. Vitamin D helps the body absorb calcium and promotes bone health, vitamin E is an antioxidant that protects cells from damage, and vitamin C is important for immune function and collagen production. However, a deficiency in these vitamins would not directly cause bleeding without clotting.

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To determine the number of pigs that can be housed in a pigsty measuring 5.0 m by 4.0 m, we need to calculate the total floor area of the pigsty. The area of the pigsty = Length x Width = 5.0 m x 4.0 m = 20.0 square meters To find the number of pigs that can be housed, we need to divide the total floor area of the pigsty by the floor space required for each pig. Number of pigs = Total area of pigsty / Floor space per pig = 20.0 m2 / 2.0 m2 per pig = 10 pigs Therefore, the correct option is 10.

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The process where bacteria remove oxygen from nitrates in the soil, resulting in the loss of nitrogen from the soil, is known as denitrification. During denitrification, bacteria convert nitrate into nitrogen gas, which is then lost to the atmosphere. This can occur in soils that are saturated with water or have low oxygen levels, which creates an environment conducive to denitrifying bacteria. Denitrification can be problematic for agricultural systems because it results in a loss of nitrogen from the soil, which can lead to decreased crop yields and environmental pollution.

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The soil water that is readily available for absorption by plant roots is called capillary water. Capillary water is held in the soil by capillary forces, which are the forces that allow water to move through narrow spaces, such as the tiny spaces between soil particles. This type of water is easily accessed by plant roots and is essential for plant growth and survival. Gravitational water, on the other hand, is water that drains out of the soil due to gravity and is not available to plants. Hygroscopic water is water that is held tightly to soil particles and is also not available to plants. Superfluous water is excess water that can lead to waterlogging and soil erosion, and is also not available to plants. Therefore, capillary water is the type of soil water that is most important for plant growth and is readily available for absorption by plant roots.

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Government finances agriculture through various means to support farmers and promote food security. These include the reduction of tariffs on agricultural inputs, granting of subsidies to farmers, establishment of agricultural colleges, and the establishment of credit sources. However, one of the options is not a way government finances agriculture. In this case, the option is "except," which implies that it is not a way government finances agriculture. Therefore, the correct answer is that all of the options listed are ways that government finances agriculture, and there is no option that is not a way government finances agriculture.

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The term that is not associated with surface irrigation is "tile". Tile drainage is a type of subsurface drainage system used to remove excess water from the soil. The other three terms, basin, dyke, and furrow, are all related to surface irrigation. - Basin irrigation is a method where water is applied to a level or gently sloping field and allowed to pond, providing water to crops from the bottom up. - Dyke irrigation involves constructing small earthen embankments to create small basins in which crops are grown. - Furrow irrigation is a method where water is applied in small channels, or furrows, between crop rows to provide water to crops.

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The price of a fixed asset at the end of its useful life is called the salvage value. This refers to the estimated amount of money that the asset can be sold for once it is no longer useful to the business. For example, if a company buys a truck for $50,000 and estimates that it will have a useful life of 10 years, at the end of the 10 years, the truck may be sold for its salvage value. This value is important for businesses to consider when they are deciding whether or not to invest in a fixed asset, as it can help them estimate the total cost of ownership over the asset's useful life. It is also important for accounting purposes, as it is used to calculate the depreciation expense for each year of the asset's useful life.

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The correct answer is: I and II only. Mulching is a farming practice where organic or inorganic materials are placed on top of the soil surface. One of the advantages of mulching is that it helps to control weeds by depriving them of sunlight, which they need to grow. Mulching also helps to conserve soil moisture by reducing evaporation from the soil surface. This helps to maintain a steady supply of moisture for crops to grow. However, mulching does not increase soil temperature and does not directly affect soil pH.

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The correct answer is: I, II, and III are all used in selecting agricultural extension teaching methods. When selecting agricultural extension teaching methods, the time available for the program, the number of farmers involved, and the agricultural needs of the farmers are all important criteria. For example, if there is limited time available for the program, methods that are quick and easy to implement, such as demonstrations or group discussions, may be preferred. If a large number of farmers are involved, methods that can be scaled up easily, such as radio broadcasts or video presentations, may be preferred. And if the agricultural needs of the farmers are diverse, methods that can be tailored to specific needs, such as individual counseling or farm visits, may be preferred. Therefore, all three criteria are important in selecting the most effective agricultural extension teaching methods.

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The earthworm is important to the farmer because it helps to improve the soil in many ways. It helps to aerate the soil by creating tunnels, which allows oxygen and water to penetrate deep into the soil. The tunnels also provide a way for roots to grow deeper, making the plants more resistant to drought. Additionally, the earthworm eats organic matter and other microorganisms in the soil, breaking them down and turning them into nutrients that plants can use. This process helps to improve soil texture and structure, making it easier for plants to grow. Finally, the earthworm helps to check soil erosion by binding soil particles together, reducing the risk of soil being washed away by heavy rain.

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The first activity to undertake before establishing a plantation is to survey the land. Surveying the land involves conducting a detailed analysis of the site where the plantation will be located. This is an essential step in the planning process as it helps to determine the suitability of the land for planting, and to identify any potential challenges or limitations that may impact the success of the plantation. The survey typically includes an assessment of the soil quality, topography, climate, and water availability. This information is used to determine the best crop to plant, as well as the most suitable planting method, fertilizer application, and irrigation system. By surveying the land, farmers are able to make informed decisions about how to develop the plantation and minimize the risks associated with crop failure or low yields. This can help to ensure the long-term viability and sustainability of the plantation, and maximize the returns on the investment.

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Pedigree selection in animal improvement is based on the performance of the ancestors. This means that animals are selected based on the performance of their parents, grandparents, and other ancestors. This is done in the belief that an animal's genetic potential for desirable traits can be inherited from its ancestors. Therefore, the selection of animals for breeding is based on the performance of their ancestors in terms of traits such as growth rate, milk production, meat quality, disease resistance, and other desirable characteristics. By selecting animals based on their pedigree, it is hoped that the desirable traits will be passed down to the next generation, resulting in improved performance of the offspring.

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The symptom that is typical of louse infestation in livestock is itching of the body. Lice are ectoparasites that live on the skin and hair of livestock and feed on their blood. As they feed, they cause irritation and itching, which can lead to the animal rubbing and scratching against hard surfaces to relieve the itching. This can result in hair loss, skin lesions, and even secondary infections. While abdominal pain and profuse salivation are symptoms of other livestock diseases, oozing out of blood is not a common symptom of louse infestation.

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Agricultural production in West Africa can be improved by several practices, including the use of modern farm implements, the application of proven agricultural research findings, and the supply of improved seeds and livestock to farmers. However, the legislation of communal land holding system is not a practice that can improve agricultural production in West Africa. In fact, communal land holding system can create challenges for farmers as it often involves multiple individuals or families sharing a single piece of land, making it difficult to implement modern farming practices or to make decisions about how to use the land. Additionally, communal land holding system can create disputes over land ownership or usage, which can lead to conflict and further hinder agricultural productivity. Therefore, while other practices can contribute to improving agricultural production in West Africa, the legislation of communal land holding system is not one of them.

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Fish ponds in arid areas should be deeper than those in the rain forests to prevent loss of fish through extreme temperatures. Arid areas have higher temperatures and lower humidity levels compared to rain forests, which can lead to high rates of evaporation and water loss from shallow ponds. By making the fish ponds deeper, the water can be stored at cooler temperatures, reducing the risk of heat stress and dehydration for the fish. This can promote healthy growth and survival of the fish in arid areas.

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The cost price of a farm equipment can be calculated using the straight-line method of depreciation. This method assumes that the value of the equipment decreases by an equal amount each year over its useful life. To calculate the cost price, we can use the formula: Cost price = Salvage value + Total depreciation The salvage value of the equipment is given as N500,000.00. The annual depreciation is given as N400,000.00, and the useful life is 10 years. Therefore, the total depreciation over the useful life of the equipment is: Total depreciation = Annual depreciation x Useful life Total depreciation = N400,000.00 x 10 Total depreciation = N4,000,000.00 Substituting the values into the formula, we get: Cost price = Salvage value + Total depreciation Cost price = N500,000.00 + N4,000,000.00 Cost price = N4,500,000.00 Therefore, the cost price of the farm equipment is N4,500,000.00.

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Marginal cost of production is defined as the increase in total cost as output is increased by one unit. In other words, it is the additional cost incurred by a firm when it produces one more unit of a good or service. This can include the cost of raw materials, labor, and any other variable costs associated with production. By calculating marginal cost, firms can make informed decisions about how much to produce, as they can compare the additional revenue generated by producing an additional unit with the additional cost of producing that unit. This can help firms optimize their production processes and maximize profits.

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Termites are useful in agriculture because they improve soil aeration. Termites are soil-dwelling insects that feed on organic matter, and in doing so, they create tunnels and burrows in the soil. These tunnels help to improve the structure of the soil and increase its permeability to water and air, which in turn enhances soil aeration. Improved soil aeration can have several benefits for agriculture. It can help to reduce soil compaction, which can improve root growth and nutrient uptake by plants. It can also improve water infiltration and retention, which can enhance crop productivity and reduce water runoff and erosion. While termites can sometimes be pests that cause damage to wooden structures, in agricultural systems they can be useful allies in promoting healthy soil ecosystems and improving crop productivity.

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One limitation to the practice of shifting cultivation in modern day agriculture is population pressure. This is because as population increases, there is less land available for shifting cultivation, and this can lead to overuse of the available land, which can cause soil degradation, reduced fertility and yield, and land-use conflicts. Additionally, population growth also leads to increased demand for food, which may require more intensive and sustainable agricultural practices to meet the demand.

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The feed conversion ratio (FCR) is the amount of feed consumed by an animal per unit of weight gain. To determine the FCR of the sheep, we divide the total amount of feed consumed by the amount of weight gained. In this case, the sheep gained 20 kg of weight after consuming 60 kg of feed. So, the FCR can be calculated as follows: FCR = Feed Consumed / Weight Gain FCR = 60 kg / 20 kg FCR = 3:1 Therefore, the feed conversion ratio of the sheep is 3:1. This means that the sheep consumed 3 kg of feed for every 1 kg of weight gain.

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