JAMB UTME - Agricultural Science - 2013

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The fertility of soils under a forest is mainly sustained by nutrient recycling. When trees and other plants in the forest shed their leaves, branches, and other organic matter, it decomposes and enriches the soil with nutrients. The decomposed organic matter also helps to retain moisture in the soil, which is important for the growth of plants. Additionally, the roots of trees and other plants help to stabilize the soil and prevent erosion. While rodent activities and the protection of the soil from direct rays of the sun and raindrops can also contribute to soil fertility in some ways, nutrient recycling is the primary factor that sustains the fertility of soils under a forest.

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The relative humidity in an incubator is usually set at 40% to 60%. This is because incubators are used to provide a controlled environment for the growth and development of organisms, such as bacteria, fungi, and cells. Maintaining the proper humidity level is essential to ensure that the organisms can grow and reproduce under optimal conditions. If the humidity is too low, the organisms may dry out and die. On the other hand, if the humidity is too high, excess moisture can lead to the growth of unwanted microorganisms, such as mold or bacteria, which can negatively impact the growth of the desired organisms. Therefore, a relative humidity range of 40% to 60% is considered ideal for most organisms, as it provides enough moisture to support their growth and development, without creating conditions that promote the growth of unwanted microorganisms.

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In biotechnology, propagation refers to the process of reproducing or multiplying a particular organism or tissue. There are different methods of propagation, but in general, the goal is to create new individuals that are genetically identical to the original. Out of the given options, the method of propagation mainly depends on the type of organism and the desired outcome. However, in general, cell culture is the most commonly used method of propagation in biotechnology. Cell culture involves growing cells in a controlled environment, usually in a laboratory setting. This method is particularly useful for growing large numbers of cells, which can then be used for various purposes, such as studying cellular functions or developing drugs. In addition, cell culture can also be used to propagate whole organisms, such as plants, by growing their cells in vitro and then inducing them to differentiate into a new plant. Grafting and aerial layering are methods commonly used for propagating plants, while binary fission is a method of reproduction used by some microorganisms. However, these methods are not as widely used in biotechnology as cell culture, which is a highly versatile and reliable technique for propagating cells and organisms.

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Continuous cropping is a farming practice that encourages the depletion of soil fertility. This is because when the same crop is planted in the same field year after year, the soil becomes depleted of essential nutrients that the crop needs to grow. Over time, this leads to a decline in soil fertility, which can result in lower crop yields and reduced quality of crops. The depletion of soil fertility can also lead to soil erosion, loss of topsoil, and increased susceptibility to pests and diseases. To maintain healthy soil and sustain crop productivity, it is important to implement practices such as crop rotation, planting of cover crops, and manual weeding, which help to replenish soil nutrients and promote soil health.

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When a farmer engages in both plant and animal husbandry, they are practicing mixed farming. Mixed farming involves raising both crops and animals on the same farm. This type of farming is beneficial for several reasons. Firstly, animal waste can be used as fertilizer for crops, reducing the need for chemical fertilizers. Secondly, crops can be used to feed the animals, reducing the need for expensive animal feed. Thirdly, animals can provide an additional source of income for the farmer through the sale of meat, dairy products, and other animal products. In contrast, crop rotation involves planting different crops in the same field in different seasons to maintain soil fertility, prevent pests and diseases, and improve crop yields. Mixed cropping involves planting two or more crops in the same field at the same time to increase productivity and reduce risks associated with mono-cropping. Lay farming, on the other hand, refers to farming on land that has not been previously farmed. Therefore, the correct term for a farmer who engages in both plant and animal husbandry is mixed farming.

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The correct term for a female cattle that has not yet had a calf or developed into the mature form of a cow is "heifer." Heifers are typically around 1-2 years old and have not yet reached sexual maturity. Once a heifer has had a calf and reached sexual maturity, she is then referred to as a cow. Stags are male cattle that have been castrated, while vealers are young cattle that are still nursing and have not been weaned. Yealing is not a correct term for a female cattle, and it is not commonly used in reference to any type of cattle.

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The tool represented in the diagram is used during the propagation method known as "budding". Budding is a form of grafting where a bud from one plant, known as the scion, is inserted into a small slit in the bark of another plant, known as the rootstock. The bud then grows and develops into a new shoot that is genetically identical to the scion. The tool in the diagram is called a budding knife, which is a specialized tool used to make precise cuts in the bark of the rootstock plant in order to insert the scion bud. So, in summary, the tool in the diagram is used during the process of budding, which is a type of grafting that involves inserting a bud from one plant into the bark of another plant.

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All of the factors of production - labor, capital, land, and management - are important for crop farming, but the most important one may vary depending on the specific context. However, a common argument is that land is the most important factor in crop farming. Land is the natural resource that provides the space for crops to grow and is a necessary component for farming to take place. Without land, there can be no crop farming. Additionally, the quality of the land, such as its fertility, water availability, and climate, can greatly impact the success of the crop. That being said, the effective use of the other factors of production, such as labor, capital, and management, can also greatly contribute to the success of crop farming. Labor provides the physical work needed to plant, maintain, and harvest crops, while capital provides the financial resources to purchase equipment, seeds, and other inputs. Good management practices, such as proper planning and decision making, can also play a critical role in the success of crop farming. So, while land may be the most important factor in a general sense, the importance of each factor can vary depending on the specific context of the crop farming operation.

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The classification of soils into sand, loam, and clay is determined by the percentage of mineral matter, such as sand, silt, and clay particles, in the soil. Sand particles are the largest and feel gritty when rubbed between your fingers. Loam is a mixture of sand, silt, and clay particles, and has a crumbly texture. Clay particles are the smallest and feel smooth and sticky when wet. Soil texture, or the relative proportion of sand, silt, and clay, is a major factor in determining a soil's ability to retain water and nutrients, and its suitability for growing different types of plants. For example, sandy soils drain quickly and are low in nutrients, while clay soils are slow to drain and may become compacted, reducing the amount of air and water available to plant roots. Loam soils have a good balance of water and air holding capacity and are considered ideal for most types of plants.

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The instrument used to measure horizontal, vertical angles, and planes is called a theodolite. A theodolite is a precision optical instrument that consists of a telescope mounted on a base with graduated circles. It has a vertical axis and a horizontal axis that allow for precise measurements of angles in both the horizontal and vertical planes. The telescope on the theodolite is used to sight a target, and then the angles can be read from the graduated circles. This allows surveyors to accurately measure angles and distances, which are crucial for creating maps, determining property boundaries, and conducting construction surveys. Overall, a theodolite is an essential tool for surveyors, and its precise measurements help ensure that their work is accurate and reliable.

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Among the given options, minimum tillage is the most suitable method for maize cultivation. Maize is a crop that requires a well-aerated soil, which can be achieved through tillage. However, excessive tillage can result in soil erosion, loss of organic matter, and soil compaction, which can be harmful to the growth of maize. Minimum tillage involves loosening the soil only in the planting rows, leaving the rest of the field undisturbed. This method helps to maintain soil structure and reduce erosion, while still providing the necessary soil aeration for maize growth. Additionally, minimum tillage can help to conserve soil moisture and reduce labor and fuel costs. Zero tillage, on the other hand, involves no tillage at all, which may not be ideal for maize cultivation as it can result in weed infestation and poor soil aeration. Maximum tillage, which involves extensive soil cultivation, can result in soil degradation and increased erosion. Contour ridges, which involve shaping the soil into ridges to control erosion, may not be necessary for all maize fields and can be more appropriate for areas with high rainfall and steep slopes.

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Checking the oil level in the engine is necessary on a daily basis for routine maintenance of a tractor. This is because the engine oil plays a crucial role in lubricating and cooling the engine components, which helps to prevent wear and tear and prolong the engine's lifespan. By checking the oil level daily, you can ensure that the engine is properly lubricated and prevent damage due to low oil levels. On the other hand, draining the gear box oil, removing and cleaning the engine's air filter, and replacing the fuel filter element are also important maintenance tasks, but they do not need to be done on a daily basis. Draining the gear box oil, for example, may be done as part of regular maintenance, such as every 50 or 100 hours of operation. Cleaning the air filter and replacing the fuel filter element may be done based on the manufacturer's recommendations, which could be every 100 or 200 hours of operation, or at a certain time interval. In summary, checking the oil level in the engine is a daily routine maintenance task for a tractor, while other maintenance tasks such as draining the gear box oil, cleaning the air filter, and replacing the fuel filter element are done less frequently based on the manufacturer's recommendations.

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Retailers may create artificial scarcity of goods by hoarding the products or under producing them. When retailers hoard products, they buy up large quantities of a particular product and hold it back from the market, creating an artificial shortage. This can lead to an increase in demand and subsequently a higher price for the product. Alternatively, retailers may intentionally under produce a product to create a scarcity, thereby increasing demand and price. By limiting the supply of a product, retailers can create a perception of rarity and exclusivity, making it more desirable to consumers who are willing to pay a premium price. Processing and price hiking are not necessarily methods that retailers use to create artificial scarcity of goods. While processing can impact the availability of a product, it is not typically done intentionally to create scarcity. Price hiking is often a result of scarcity, rather than a method to create it.

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The most devastating agent of erosion is "run-off water". When it rains, water can flow across the land, picking up sediment, soil, and other materials as it goes. This process is called erosion, and it can have serious impacts on the environment. Run-off water is particularly powerful because it can carry a large amount of material over long distances, and it can easily cut through soil and rock. In areas with steep slopes or unprotected soil, run-off water can cause massive erosion that can result in the loss of topsoil, damage to infrastructure, and even the destruction of entire ecosystems. Run-off water erosion can be worsened by factors such as deforestation, improper land use, and climate change, so it's important to take steps to prevent and manage this type of erosion.

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The combination of inputs that enhances healthy growth of crops is irrigation and fertilizer. Irrigation refers to the process of supplying water to crops, and it is essential for their growth because water is one of the primary components that plants need to survive. Fertilizers, on the other hand, are chemical or organic compounds that provide essential nutrients to plants, such as nitrogen, phosphorus, and potassium. These nutrients help plants grow strong and healthy, and they also help them resist disease and pests. When these two inputs are combined, they create the optimal conditions for plant growth. Irrigation ensures that the plants have access to water at all times, which helps them absorb the nutrients from the fertilizer more effectively. Fertilizer, in turn, provides the plants with the nutrients they need to grow quickly and vigorously. In contrast, the other combinations of inputs listed are not as effective for promoting healthy crop growth. Tractors and cash may be useful for purchasing inputs like fertilizer and irrigation systems, but they do not directly contribute to plant growth. Work bulls and implements are traditional methods of farming that may not be as efficient as modern irrigation and fertilization techniques. Finally, cutlasses and sacks are useful for harvesting crops, but they do not provide the necessary inputs for plant growth.

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In female farm animals, a sign of heat is the presence of secretions from the vulva. This is because during this time the animal is ready to mate and produce offspring. The secretions are a way of signaling to male animals that the female is in heat and ready to mate. It is important to note that these secretions can vary in appearance and odor, but they are a clear indication that the female is in heat.

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The group of crops that are mostly cultivated in the rainforest zone of Nigeria are maize, cocoyam and cassava. Rainforest zones in Nigeria have high rainfall and humidity, which make them suitable for the cultivation of crops that require a lot of water. Maize is a staple crop in Nigeria and is grown in both the rainforest and savanna zones. Cocoyam, which is a root crop, is also commonly grown in the rainforest region. Cassava is another root crop that is grown in this region and is a major source of food and income for many farmers in Nigeria. Millet, yam and coconut are crops that are typically grown in drier areas, such as the savanna zone. Sorghum, sweet potato and date are also crops that can tolerate drier conditions and are not commonly grown in the rainforest zone. Wheat, Irish potato and groundnut are crops that are not typically grown in Nigeria due to unsuitable climatic conditions.

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In farm animals, gonads are organs associated with reproduction. Gonads are the organs responsible for producing gametes (sperm in males and eggs in females), which are needed for sexual reproduction. In males, the gonads are called testes and they produce sperm. In females, the gonads are called ovaries and they produce eggs. These gametes are necessary for the fertilization of eggs and the production of offspring. Therefore, the gonads are crucial organs in the process of reproduction in farm animals.

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Farm labour is usually measured in terms of hours or days of work by labour. Farm labour refers to the work done by people on a farm, such as planting, cultivating, and harvesting crops, tending to livestock, and maintaining equipment and infrastructure. It is one of the primary inputs in agricultural production, alongside land, capital, and other resources. The most common way to measure farm labour is by the amount of time that labourers spend working on the farm, which is typically expressed in hours or days. This measurement is useful for several reasons. Firstly, it allows farmers to estimate the total amount of work that needs to be done and plan accordingly, for example, by hiring more workers during peak seasons. Secondly, it enables farmers to calculate the cost of labour, which is a significant expense in agricultural production. Finally, it provides a basis for evaluating the efficiency of labour and identifying ways to improve productivity. While the other options listed may also be relevant to farm labour, they are not the primary ways in which it is measured. The amount of wages paid to labour, for example, is determined by the hours or days of work performed, as well as the prevailing wage rates in the local labor market. The level of education of labour may influence their productivity and ability to perform certain tasks, but it does not directly measure the amount of work done. Similarly, the type of work done by labour is relevant for understanding the specific tasks that need to be performed, but it does not provide a comprehensive measure of the overall amount of work done.

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Pedigree selection is the process of selecting individuals for breeding based on the performance of their ancestors. This approach assumes that the genetic makeup of an individual is influenced by the genetic background of their parents, grandparents, and other ancestors. By selecting individuals with superior ancestors, it is believed that their offspring will inherit favorable genes that contribute to desirable traits such as increased yield, disease resistance, or improved growth. In summary, pedigree selection is a strategy for improving the genetic quality of a population by using the performance of ancestors as a basis for selection.

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The causative organism of Avian influenza is a virus. Avian influenza, also known as bird flu, is a highly infectious viral disease that affects birds, particularly poultry. The virus responsible for avian influenza is primarily transmitted among birds through their respiratory and digestive systems. The virus can also be transmitted to humans, and in rare cases, it can cause serious illness or even death. It is important to note that avian influenza is not caused by a bacterium, fungus, or protozoan, but by a specific type of virus called the avian influenza virus.

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The energy obtained from the sun is called solar energy. Solar energy is a type of renewable energy that is generated by the sun's radiation. This energy is captured by solar panels and converted into electricity, which can be used to power homes, businesses, and even entire cities. Solar energy is a clean, green and sustainable form of energy that does not produce any harmful emissions or pollution. It is also abundant and widely available, making it a popular choice for people who want to reduce their carbon footprint and help protect the environment.

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The parts of plants that are commonly used for vegetative propagation are the stem, root, and leaf. Vegetative propagation is a type of asexual reproduction, where new plants are produced from the vegetative parts of the parent plant, without the involvement of seeds. Stem cuttings are a popular method of vegetative propagation, where a piece of the stem from the parent plant is cut off and placed in water or soil. The cutting will eventually develop roots and grow into a new plant. Root cuttings can also be used for vegetative propagation, where a section of the root is cut off and planted in soil. The root cutting will develop new shoots and grow into a new plant. Leaf cuttings can also be used for propagation in some plant species, where a healthy leaf is removed from the parent plant and placed in a growing medium. The leaf will develop roots and grow into a new plant. In conclusion, the stem, root, and leaf are the parts of plants that are commonly used for vegetative propagation, allowing gardeners and farmers to create new plants without the need for seeds.

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The anti-sterility vitamin in livestock's nutrition is vitamin E. This vitamin is essential for proper reproductive function in animals, particularly in females. It plays an important role in maintaining the health of the reproductive organs, including the uterus and ovaries, and can also improve sperm quality in males. Vitamin E is an antioxidant, which means it helps to protect cells from damage caused by harmful molecules called free radicals. When free radicals accumulate in the body, they can cause oxidative stress, which can damage cells and tissues. This can lead to a variety of health problems, including infertility. Livestock that are deficient in vitamin E may experience reduced fertility, including decreased conception rates, increased rates of miscarriage, and lower birth weights. Additionally, vitamin E can help to boost the immune system, which can protect animals from infections that could also lead to infertility. In summary, vitamin E is the anti-sterility vitamin in livestock's nutrition because it is essential for reproductive health and can help to protect against oxidative stress and infection.

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The serious pest of sweet potato whose larvae destroy the foliage is the leaf miner. Leaf miners are small insects whose larvae tunnel inside the leaves, creating distinctive winding trails or "mines" as they feed. The damage caused by leaf miners can reduce the plant's ability to produce food through photosynthesis and weaken the plant's overall health, potentially reducing the yield of sweet potato tubers. Leaf miners can be controlled through a variety of methods, such as using insecticides, introducing natural predators, or practicing cultural control measures like removing infested leaves or planting resistant varieties. Early detection and proper management are important for preventing severe infestations and minimizing crop losses.

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Cassava mosaic disease is transmitted by an insect called Bemisia nigerensis. This insect, also known as the whitefly, feeds on the cassava plant and spreads the disease by carrying the virus from infected plants to healthy ones. The virus can also be spread through contaminated plant material or by using infected tools during planting. Once the virus infects a cassava plant, it causes yellowing and distortion of the leaves, stunted growth, and reduced yields. The disease can have devastating effects on cassava crops, which are a staple food source for millions of people in Africa.

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The farmer should stop adding input at point III. Point III represents the point of diminishing returns, where the increase in output from adding more input starts to decrease. In other words, the farmer will get less and less additional output for each unit of input they add after this point. For example, adding more fertilizer may result in a larger increase in crop yield up to a certain point, but beyond that point, adding more fertilizer may not result in much of an increase in yield. It is important for the farmer to recognize this point and stop adding input, as continuing to add input beyond point III will not result in a significant increase in output, but will still increase the cost of production.

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The major reason which necessitates the expansion of agriculture is the increase in population. As more people are born and as medical advancements increase the lifespan of individuals, the number of people who need food also increases. Agriculture is the primary source of food production, and expanding agricultural practices is necessary to keep up with the growing demand for food. With more people to feed, there is a greater need for more land to be cultivated and for more crops to be grown. While factors such as rainfalls, manpower, and animal power can also play a role in agricultural expansion, population growth is the primary driving force behind the need to expand agriculture.

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An example of igneous rock is basalt. Igneous rocks are formed from the solidification and cooling of magma or lava. Basalt is an extrusive igneous rock, which means it formed from lava that erupted onto the Earth's surface and cooled quickly. Basalt is a dark-colored rock that is typically fine-grained and dense. It is commonly found in areas of volcanic activity, such as mid-ocean ridges and hotspot volcanoes. It is also used as a building material and in road construction due to its durability and strength.

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The process of mating in poultry is referred to as "treading". Treading is when a male bird mounts the female bird and presses his feet on her back while flapping his wings. This behavior stimulates the female to ovulate and release an egg, which can then be fertilized by the male's sperm. This process is essential for reproduction in poultry and is necessary to ensure the continuation of the species.

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When it comes to a mechanized farm that is mono cropped, the most suitable planting pattern is drilling. Drilling refers to the process of placing seeds in the soil using a specialized machine called a drill seeder. This method allows for precise seed placement and spacing, which promotes even crop emergence and growth. Drilling also reduces seed waste, as the machine can accurately distribute seeds in the desired pattern and depth. In contrast, band placement and side dressing are methods of applying fertilizers to the soil, not planting. Top dressing, on the other hand, refers to the application of fertilizer on the soil surface after planting. While these methods can be beneficial for crop growth, they do not address the question of planting pattern. Therefore, for a mechanized farm that is mono cropped, drilling is the most suitable planting pattern as it promotes efficient and uniform seed placement, which can lead to improved crop yields and better overall efficiency.

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Floriculture deals with the study of flowers. It is a branch of horticulture that involves the cultivation of flowers and ornamental plants for commercial and decorative purposes. Floriculturists study the growth, development, and breeding of flowers to enhance their beauty, color, fragrance, and resistance to disease. They also work to develop new varieties of flowers and plants that are more durable, have longer lifespans, and require less maintenance. The flowers produced through floriculture are used for a variety of purposes, including decoration, landscaping, and as gifts for special occasions like weddings and birthdays.

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The farm animal that is considered monogastric is the pig. Monogastric refers to animals that have a single-chambered stomach that functions as a simple, acidic storage and digestion chamber. In other words, monogastric animals have a stomach that is not divided into multiple compartments. Pigs have a monogastric digestive system, meaning that they have a single-chambered stomach just like humans. They digest their food through a process that involves the breakdown of food in the stomach and small intestine with the help of enzymes and acid. In contrast, ruminant animals such as cows and sheep have a four-chambered stomach that allows them to digest tough plant material more efficiently. They use a process called rumination, which involves regurgitating and re-chewing their food to break it down further. Therefore, the pig is the only animal in the given options that has a monogastric digestive system, while the others have multi-chambered digestive systems.