WAEC SSCE - Agricultural Science - 1993

Détails de la réponse

The aim of a plant breeder in producing a crop variety that is tolerant to extreme cold, drought, wind, and heat is based on the adaptation of the variety to climate conditions. Climate conditions can greatly impact the growth and productivity of crops. For instance, extreme cold can damage crops and delay their growth, while drought can reduce their yield and quality. Plant breeders work to develop crop varieties that are well-suited to the environmental conditions in which they will be grown. They select for traits that are known to improve a plant's ability to withstand cold, drought, wind, and heat stress. These traits can include deeper root systems, thicker leaves, and improved water-use efficiency. By developing crop varieties that are adapted to specific climate conditions, plant breeders can help farmers produce better yields and more consistent crops, even in challenging environments. This can help ensure food security and sustainability, especially in regions that are prone to extreme weather events or other environmental stressors. In summary, the aim of a plant breeder in producing a crop variety that is tolerant to extreme cold, drought, wind, and heat is based on the adaptation of the variety to climate conditions, which can greatly impact crop growth and productivity.

Détails de la réponse

The part of the egg that prevents the yolk from being damaged by keeping it at the center of the egg is called the chalaza. The chalaza is a twisted, rope-like structure made of protein fibers that extend from the yolk to the opposite ends of the egg. It serves to anchor the yolk in place and prevent it from bumping against the eggshell or other parts of the egg. When an egg is cracked open, the chalaza can be seen as two white, cord-like structures attached to the yolk. The chalaza is not to be confused with the egg membrane, which is a thin membrane that surrounds the egg white and yolk. The germ spot, also known as the blastoderm, is a small, circular spot on the surface of the yolk where the fertilized egg begins to develop. The albumen, or egg white, is a clear, viscous fluid that surrounds the yolk and provides a source of protein for the developing embryo. The air space is a pocket of air that develops between the eggshell and the egg white as the egg ages.

Détails de la réponse

When there is a large quantity of food items in the market, and other factors remain constant, the demand will increase, and the price will decrease. This is because there is more supply than demand, and the sellers will try to attract buyers by reducing the price of the food items. When there is an abundance of food items in the market, buyers have more options to choose from, and they can afford to be more selective. Therefore, sellers have to compete with each other to sell their products, and they may lower the prices to attract customers. On the other hand, if the demand decreases, and the quantity of food items remains the same, the sellers may increase the prices of the food items to maintain their profit margins. This is because they have fewer customers to sell to, and they need to make up for the lost revenue. Therefore, the correct answer is "demand will increase, and price will decrease."

Détails de la réponse

Détails de la réponse

Livestock farmers may face challenges of feed shortages during the dry season when grass and other vegetation may not be as readily available. To overcome this challenge, farmers can prepare a mixture of pasture legumes and grasses which are cut and preserved for later feeding of their livestock. This mixture, when cut and preserved while retaining some moisture, is referred to as "silage." Silage is a fermented feed that is made by chopping the green forage, mixing it together, and storing it in an airtight container. The mixture is then allowed to ferment, which preserves the nutrients and increases the digestibility of the feed. Silage is an excellent feed for livestock during the dry season because it retains moisture, which is beneficial for the animals' health. Additionally, the fermentation process can help to reduce spoilage and maintain the nutritional value of the feed for longer periods than other types of preserved feed, such as hay or soilage. Hay is a feed that is cut, dried and stored for feeding animals later, whereas soilage is a feed made by storing whole crop maize, oats or other crops in a silo. Fodder is a general term for feed given to animals, and creep feed is a special type of feed given to young animals in a separate feeding area to supplement their milk diet. Therefore, the correct answer is "silage."

Détails de la réponse

The important management practice that is not associated with the husbandry of piglets is "provision of grass beddings for piglets." The other three options are common management practices in piglet husbandry, while the provision of grass beddings is not common. Grass bedding may not be practical for piglets, as it may not provide adequate warmth, comfort, and hygiene, which are necessary for their healthy development. Instead, materials such as straw, wood shavings, or sawdust are commonly used as bedding for piglets. Castration of male piglets not needed for breeding is done to avoid aggressive behavior and the unpleasant taste of pork from sexually mature males. Administration of drugs containing iron to piglets is essential for preventing anemia, which is a common condition in piglets due to their high iron requirements. Cutting of the needle teeth of piglets is necessary to prevent injuries to their littermates and nursing sow.

Détails de la réponse

Seed germination is a farm operation that cannot be mechanized. Seed germination is a natural process that occurs when a seed is exposed to the right conditions of moisture, temperature, and air. It is a biological process that cannot be controlled by machinery or automated processes. While there are technologies and equipment that can help to create the optimal conditions for seed germination, such as seed drills, irrigation systems, and greenhouses, the process itself is dependent on factors that are outside of human control. In contrast, the other farm operations listed in the options - weed control, fertilizer application, transportation and handling, and crop processing - can all be mechanized to some extent. For example, there are machines that can apply fertilizers and herbicides to crops, transport harvested crops, and process crops for storage or consumption.

Détails de la réponse

Breeding in self-pollination crops can be regarded as inbreeding. Self-pollination is a type of reproduction in which the pollen from the male part of a flower fertilizes the female part of the same flower or another flower on the same plant. In self-pollination crops, such as wheat, rice, and soybeans, the flowers are typically self-fertile, meaning they contain both male and female reproductive organs, and can fertilize themselves without the need for pollen from other plants. Inbreeding is the process of mating closely related individuals, such as siblings or cousins, within a population. In self-pollination crops, inbreeding can lead to the development of homozygous lines, which have two identical alleles for a particular gene. Homozygous lines are desirable in plant breeding because they produce offspring that are genetically uniform and can be reliably propagated. Line breeding, cross-breeding, hybridization, and back-crossing are other breeding methods that can be used in plant breeding, but they involve the use of different breeding techniques and may not be suitable for self-pollination crops.

Détails de la réponse

The vegetable that is not a leafy vegetable is "lycopersicon esculentum". Lycopersicon esculentum, commonly known as tomato, is not a leafy vegetable. It is actually a fruit that is used as a vegetable in cooking. On the other hand, amaranthus spp, celsosia spp, corchorus spp, and telfaria occidentalis are all examples of leafy vegetables. Leafy vegetables are edible plants that are primarily valued for their leaves, which are consumed as a vegetable. They are a good source of nutrients such as vitamins, minerals, and dietary fiber, and are important components of a healthy diet. Therefore, lycopersicon esculentum, also known as tomato, is the vegetable that is not a leafy vegetable.

Détails de la réponse

Providing adequate plant cover is the best way to reduce surface run-off on farmlands. When plants are present, they act as a physical barrier that slows down the movement of water across the soil surface. Plant roots also help to bind soil particles together, making it less likely for the soil to be eroded by surface run-off. This results in improved soil fertility, water conservation, and increased crop yields. Therefore, farmers can use crops that provide good ground cover to reduce surface run-off, such as cover crops, legumes, and grasses.

Détails de la réponse

The option that is not a problem of agricultural marketing in Nigeria is "high quality of farm produce". In Nigeria, agriculture plays a significant role in the economy, and marketing of agricultural products is an essential aspect of agriculture. However, several problems are associated with agricultural marketing in Nigeria, including lack of transport facilities, scattered sources of supply, lack of good packaging and processing facilities, and instability of prices. The high quality of farm produce is not a problem in agricultural marketing in Nigeria, but rather it is desirable. In fact, the quality of agricultural products is an important factor that determines the demand and price of such products. Therefore, farmers are encouraged to produce high-quality products to meet the market demand, and this can enhance the profitability of their agricultural ventures.

Détails de la réponse

The term ginning applies to cotton. Ginning is a process used to separate the seeds from cotton fibers. After cotton is harvested, the fibers are separated from the seeds using a machine called a gin. The cotton fibers are then used to make a variety of products, including clothing, bed sheets, and towels. Oil palm, cocoa, groundnut, and coconut do not require ginning. Oil palm and coconut produce oil, while cocoa and groundnut produce seeds that are used to make various products. However, these crops may require other post-harvest processing methods to separate the desired part of the crop from unwanted materials. In summary, the term ginning is associated with the processing of cotton and does not apply to oil palm, cocoa, groundnut, or coconut.

Détails de la réponse

All the crops listed in the options can be processed into a powdered form for effective preservation except for kolanut. Maize, yam, pepper, and soya bean can all be processed into a powdered form for preservation. Powdering these crops makes them last longer and helps to retain their nutritional value. Maize can be dried and ground into cornmeal, yam can be sliced and dried before grinding into flour, pepper can be ground into powder, and soya bean can be roasted, ground, and used as a protein supplement. Kolanut, on the other hand, is a bitter stimulant that is commonly used in social and cultural events in Nigeria. While it can be processed into various forms for consumption, it is not typically processed into a powdered form for preservation.

Détails de la réponse

The symptoms of coffee leaf rust are leaf spots, loss of vigour, and death of the leaves. Coffee leaf rust is a fungal disease that affects coffee plants, causing damage to the leaves and reducing yield. The first symptom of coffee leaf rust is the appearance of small, yellow-orange spots on the leaves. These spots gradually enlarge and turn brown, and may merge to form large lesions that cover the entire leaf surface. As the disease progresses, the affected leaves lose their vigour and may become twisted or curled. Eventually, the leaves may turn yellow and fall off the plant, leading to defoliation and a reduction in photosynthesis. This can weaken the plant and reduce its ability to produce coffee cherries, resulting in lower yields and quality. Coffee leaf rust is a serious problem in many coffee-growing regions, and can be difficult to control. Prevention and early detection are key to minimizing the impact of the disease. Farmers can use cultural practices, such as pruning and removing infected leaves, and chemical fungicides to manage coffee leaf rust.

Détails de la réponse

Détails de la réponse

Détails de la réponse

Détails de la réponse

The aims of breeding in farm animals include improving the production potentials of farm animals, improving the quality of animal products, improving adaptability of farm animals to a new environment, and increasing tolerance of animal to disease and pests. Therefore, the option that is not included in the aims of breeding is "evolving new breeds of animals suitable for all purposes."

Détails de la réponse

Carrying capacity is the term used to describe the number of animals that can be conveniently supported on a given unit of land, such as a hectare of pasture. It is determined by a variety of factors, including the quality and quantity of the available forage, the climate, and the soil fertility. The carrying capacity of a piece of land is an essential consideration for livestock farmers, as it helps to determine how many animals they can sustainably raise on a given piece of land. If the carrying capacity is exceeded, it can lead to overgrazing, soil erosion, and a decline in the overall health of the pasture. Biological value refers to the quality of protein in a feed, while nutritive value is a measure of the overall nutritional content of a feed. Livestock quality is a term that refers to the genetic potential of an animal for desirable traits, such as growth rate, milk production, or meat quality. Zero grazing is a management system in which animals are kept in a confined area and fed cut forage rather than grazing on pasture. Therefore, the correct answer is "carrying capacity."

Détails de la réponse

The cracks or crevices that are first noticed on rocks during the process of soil formation are typically caused by "temperature". Temperature changes can cause rocks to expand and contract, which can lead to the formation of cracks or crevices. This is particularly true in areas with a wide range of temperatures, where rocks may experience rapid heating and cooling cycles. For example, in desert regions, rocks can become very hot during the day and cool down rapidly at night, which can cause them to expand and contract, and eventually break apart. While other factors such as ice, wind, and solution can also contribute to the formation of cracks or crevices on rocks, temperature is often the primary cause. Ice can cause rocks to crack through a process known as freeze-thaw weathering, while wind can cause abrasion and wear. Solution can dissolve certain types of rock, particularly those that contain minerals such as limestone, which can lead to the formation of caves and other geological features. However, these processes typically occur over longer periods of time than the rapid temperature changes that cause rocks to crack. Therefore, temperature is the factor that is most likely to cause the initial cracks or crevices on rocks during the process of soil formation.

Détails de la réponse

Détails de la réponse

Détails de la réponse

Détails de la réponse

The statement that is not correct about micronutrients is that they are the most abundant elements in plant leaves. Micronutrients are essential elements required by plants in small quantities for proper growth and development. They act as catalysts and co-enzymes in various physiological processes such as photosynthesis, respiration, and cell division. Although micronutrients are required in small amounts, they play a critical role in plant growth and development. However, when present in large quantities, some micronutrients such as copper, manganese, and zinc can be toxic to plants. These elements are derived from the parent rocks and can be found in varying concentrations in soil. In contrast to the statement, the most abundant elements in plant leaves are carbon, hydrogen, and oxygen, which are obtained from air and water through photosynthesis. Therefore, the correct statement is "micronutrients are not the most abundant elements in plant leaves."

Détails de la réponse

The control measure that is not effective against cowpea weevils is "innoculation of seeds". Cowpea weevils are pests that infest cowpea seeds, and can cause significant damage to the crop. To control cowpea weevils, several measures can be taken, including fumigation of stored seeds, storage of seeds in air-tight containers, timely harvesting, and dusting seeds with 0.5% lindane dust. However, "innoculation of seeds" is not a control measure for cowpea weevils. Inoculation refers to the process of introducing a microorganism or other biological agent to stimulate growth or provide protection against disease or pests. Inoculation may be effective for other pests or diseases, but not for cowpea weevils. Therefore, it is not a recommended control measure for this particular pest.

Détails de la réponse

The process that will not lead to the loss of nutrients from the soil is mulching. Mulching is the process of adding organic matter to the soil surface, which helps to retain moisture, suppress weed growth, and improve soil fertility. When organic matter such as leaves, grass clippings, or crop residues are added to the soil surface, they slowly decompose, releasing nutrients back into the soil. This process is beneficial for the soil and does not lead to the loss of nutrients. On the other hand, erosion, harvesting, burning, and leaching can all lead to the loss of nutrients from the soil. Erosion occurs when wind or water carries away the top layer of soil, which often contains the most nutrient-rich organic matter. Harvesting involves removing crops from the soil, which also removes nutrients. Burning organic matter can release nutrients into the atmosphere, which can be lost from the soil. Finally, leaching occurs when excess water carries away nutrients from the soil, making them unavailable for plant growth. In summary, while erosion, harvesting, burning, and leaching can lead to the loss of nutrients from the soil, mulching is a process that adds nutrients to the soil and is beneficial for soil health.

Détails de la réponse

The quality of balanced diet supplied to an animal per day is described as the ratio. The ratio refers to the proportion of different nutrients that are present in an animal's diet. A balanced diet for an animal should contain the right amount of protein, carbohydrates, fats, vitamins, and minerals that are necessary for its growth and maintenance. The ratio of these nutrients in an animal's diet can be expressed as a percentage or a ratio. For example, a common ratio for a balanced diet for dairy cows is 60:40 for roughage to concentrate, meaning that 60% of the diet is made up of roughage (such as hay or grass) and 40% is made up of concentrate (such as grains or pellets). The ratio of nutrients in an animal's diet is important for maintaining its health and productivity. A diet that is unbalanced or deficient in certain nutrients can lead to health problems, poor growth or weight gain, and reduced milk or meat production. In summary, the ratio is a measure of the quality of a balanced diet supplied to an animal per day, and it represents the proportion of different nutrients that are present in the diet.

Détails de la réponse

Cassava and sugarcane are mainly propagated by cutting. Propagation refers to the process of reproducing a plant. Cutting is a form of asexual propagation, which involves taking a piece of stem, leaf, or root from the parent plant and using it to grow a new plant. Cassava and sugarcane can be propagated by cutting because they have the ability to regenerate new roots from the cuttings. To propagate cassava and sugarcane by cutting, a healthy stem is cut into small sections, usually about 20-30 cm long, and planted in a well-prepared soil. The cuttings are planted at an angle and covered with soil, leaving only a few centimeters above the ground. The soil should be kept moist to help the cuttings establish new roots. In a few weeks, new shoots will emerge, and the cutting will develop into a new plant. Cutting is an easy and inexpensive method of propagation that allows farmers to produce a large number of plants from a single parent plant. It is a common method of propagating cassava and sugarcane because they can produce healthy and high-yielding plants with a good quality harvest.

Détails de la réponse

Bull calves intended for breeding are sometimes nose-ringed in order to facilitate easy handling of the bull. Nose rings are commonly used as a means of control and training for bulls. They are attached to a rope or chain that can be pulled to lead the bull or to control its movements. The nose ring helps to calm the animal and prevent it from becoming aggressive or difficult to handle. Additionally, nose-rings may be used to help identify individual animals or to prevent them from damaging fences or other objects.

Détails de la réponse

Carbon dioxide is used by crops during photosynthesis. Photosynthesis is a natural process by which plants, algae, and some bacteria use sunlight, water, and carbon dioxide to produce glucose (sugar) and oxygen. In this process, carbon dioxide is taken in by the plant's leaves, and using the energy from sunlight, it is converted into glucose, which is used by the plant for growth and energy. Oxygen is also released into the atmosphere as a by-product of photosynthesis. The process of recycling carbon in nature involves the exchange of carbon between living organisms and the environment. Plants take in carbon dioxide during photosynthesis and use it to produce glucose, which becomes part of their tissues. When the plants die or are eaten by animals, the carbon in their tissues is released back into the environment through respiration or decomposition. This carbon can then be used by other plants during photosynthesis, completing the carbon cycle.

Détails de la réponse

One of the sexually transmitted diseases in livestock is brucellosis. Brucellosis is a bacterial disease that affects various livestock species, including cattle, goats, and sheep. The disease is primarily spread through direct contact with infected animals, but it can also be transmitted through contaminated feed, water, or equipment. In livestock, brucellosis can cause abortions, reduced milk production, and infertility. Infected animals may also exhibit symptoms such as fever, weight loss, and swollen joints. In addition to being a threat to animal health, brucellosis can also be transmitted to humans through contact with infected animals or consumption of contaminated dairy products. Preventing the spread of brucellosis in livestock requires measures such as testing and culling infected animals, vaccination, and good biosecurity practices, such as quarantining new animals before introducing them to the herd. Farmers and veterinarians should also take precautions to protect themselves from infection when handling potentially infected animals or tissues. In summary, brucellosis is a sexually transmitted disease in livestock that can cause serious health problems and economic losses. Preventive measures such as testing, vaccination, and good biosecurity practices can help to control the spread of this disease.

Détails de la réponse

Détails de la réponse

The disadvantage of land fragmentation that is not listed above is facilitating the use of simple and cheap tools. Land fragmentation refers to the division of large landholdings into smaller plots, often resulting in irregularly shaped, scattered land parcels. This practice can lead to several disadvantages, including difficulty in implementing soil conservation practices, unsuitability for mechanization, wastage of labor and time, and increased soil erosion. Facilitating the use of simple and cheap tools, however, is not a disadvantage of land fragmentation. In fact, it can be seen as an advantage in some cases, as it allows farmers to use basic tools and technologies that are more affordable and easier to maintain than complex machinery. However, the other disadvantages of land fragmentation can have significant negative impacts on agricultural productivity and efficiency, as well as on the livelihoods of farmers. Difficulty in implementing soil conservation practices can lead to soil erosion and reduced soil fertility over time, while the unsuitability of mechanization can limit the ability of farmers to adopt more efficient farming methods. Wastage of labor and time can also reduce overall productivity and increase costs, which can be especially challenging for small-scale farmers with limited resources. In summary, while facilitating the use of simple and cheap tools can be seen as an advantage of land fragmentation, the other disadvantages, including difficulty in implementing soil conservation practices, unsuitability for mechanization, wastage of labor and time, and increased soil erosion, can have significant negative impacts on agricultural productivity and efficiency.

Détails de la réponse

The soil nutrient which is important as a constituent of plant proteins and hormones is sulfur. Sulfur is a macronutrient that plays a crucial role in the growth and development of plants. It is a constituent of amino acids, which are the building blocks of proteins. Proteins are essential for the structure and function of cells, tissues, and organs in plants, and they are involved in many biological processes such as photosynthesis, respiration, and defense against pests and diseases. Sulfur is also important for the synthesis of hormones such as auxins and cytokinins, which regulate plant growth and development. These hormones control cell division, elongation, and differentiation, and they are involved in many aspects of plant physiology such as root growth, flower and fruit development, and stress responses. In addition to its role in protein and hormone synthesis, sulfur is also involved in other functions such as chlorophyll formation, enzyme activation, and nutrient uptake. Therefore, it is important to maintain adequate levels of sulfur in the soil to ensure healthy plant growth and development.

Détails de la réponse

The botanical name of giant star grass is Cynodon plectostachyum. Giant star grass is a tropical grass species that is commonly used for forage production in many parts of the world. It is known for its high yield potential and nutritional value, making it an important feed source for livestock. The grass has a dense growth habit, which helps to prevent weed growth and soil erosion. The scientific naming system for plants is called binomial nomenclature. It was developed by Carl Linnaeus in the 18th century and involves giving each plant a two-part name: a genus name and a species name. The genus name refers to a group of related plants that share similar characteristics, while the species name refers to a specific plant within that genus. In this case, the genus name is Cynodon, which refers to a group of grasses that are commonly used for forage production. The species name is plectostachyum, which is a unique name given to this particular type of giant star grass. Therefore, the correct botanical name for giant star grass is Cynodon plectostachyum.

Détails de la réponse

Deweeding is the pond maintenance operation that will ensure adequate supply of oxygen and hygienic condition for fish in a pond. Weeds and other aquatic plants can grow rapidly in fish ponds and can reduce the oxygen supply in the water, leading to poor water quality and fish mortality. By removing weeds and other aquatic plants from the pond, more oxygen can dissolve in the water and the water quality can improve. This helps to create a more suitable environment for the fish to grow and thrive. Deweeding also helps to prevent the buildup of organic matter in the pond, which can contribute to the growth of harmful bacteria and parasites. Removing weeds and other debris from the pond can also help to prevent clogging of the pond and maintain a steady flow of water, which is essential for the health and wellbeing of the fish. In summary, deweeding is an important pond maintenance operation that ensures adequate supply of oxygen and hygienic conditions for fish in a pond by removing weeds and other aquatic plants, preventing the buildup of organic matter, and maintaining a steady flow of water.

Détails de la réponse

Efficient management is not an effect of a badly arranged farm. Efficient management refers to the ability to plan, organize, and supervise farm operations in a way that maximizes productivity and profitability. While a poorly arranged farm can lead to time wastage, expensive labor, low output, and low profit, it does not necessarily affect efficient management. In fact, efficient management is critical for overcoming the challenges that arise from a badly arranged farm. A skilled and experienced farm manager can identify the problems associated with a poorly arranged farm and implement strategies to improve productivity and profitability. Therefore, it is essential to prioritize efficient management practices in order to optimize farm operations, reduce costs, and increase profits, regardless of the arrangement of the farm.

Détails de la réponse

The cracking of eggs laid by a flock of layers in a farm can be corrected by increasing the amount of calcium, phosphorus, and vitamin D in their feed. Eggshell quality is influenced by several factors, including the nutrients that are available in the diet of the hens. Calcium, phosphorus, and vitamin D are important nutrients for the formation and quality of eggshells. When hens do not get enough of these nutrients in their diet, their eggshells become weak and brittle, which can result in cracking of eggs. By increasing the amount of calcium, phosphorus, and vitamin D in the feed of the layers, their eggshell quality can be improved, and the incidence of cracked eggs can be reduced. It is essential to ensure that the feed is of high quality and is formulated to meet the specific nutritional requirements of the layers. Other factors that can affect eggshell quality include environmental stress, disease, and genetics. Therefore, it is important to maintain a clean and stress-free environment for the layers and to implement appropriate disease prevention measures.

Détails de la réponse

The source of energy used by green plants for photosynthesis is the sun. Photosynthesis is the process by which green plants use light energy to convert carbon dioxide and water into glucose (sugar) and oxygen. The process occurs in chloroplasts, which are organelles found in plant cells. Chlorophyll, a pigment found in chloroplasts, absorbs light energy from the sun and uses it to power the photosynthesis process. Therefore, green plants require sunlight to carry out photosynthesis and produce the energy needed for their growth and survival. Without sunlight, the process cannot occur, and plants will not be able to produce the food and energy they need to survive. So, the sun is the ultimate source of energy for green plants.

Détails de la réponse

The hormone that prevents abortion or expulsion of the fetus during pregnancy is progesterone. Progesterone is a hormone that is naturally produced by the ovaries after ovulation. During pregnancy, progesterone is produced in large amounts by the placenta to maintain the pregnancy. One of the key functions of progesterone during pregnancy is to prevent the uterus from contracting and expelling the fetus. It does this by relaxing the smooth muscles of the uterus, which helps to maintain a stable and supportive environment for the growing fetus. Without enough progesterone, the uterus may start to contract, which can lead to a miscarriage or premature delivery. Therefore, progesterone plays a crucial role in ensuring the successful continuation of a pregnancy.

Détails de la réponse

Détails de la réponse

A soil which consists of a mixture of sand, silt, and clay in equal quantities is described as loam. Loam soils have a balanced mixture of sand, silt, and clay particles, making it a very productive soil type for farming. The sandy part of loam soil helps with drainage, while the clay part helps with water retention. Additionally, loam soil has high nutrient content due to the presence of organic matter, making it ideal for growing a wide range of crops.

Détails de la réponse

Cassava mosaic virus is a plant disease that affects cassava plants, a major food crop in many African countries. The disease is caused by a virus that is transmitted by whiteflies and causes severe damage to the plant, including stunted growth, yellowing of leaves, and reduced yields. To control cassava mosaic virus, several strategies can be employed. However, the most effective strategy is to grow resistant varieties of cassava that are less susceptible to the virus. These varieties have been developed through breeding programs and are now widely available to farmers. Other methods of controlling the virus include treating stem cuttings with hot water or insecticides to kill any viruses that may be present, and spraying with insecticides to control the whiteflies that transmit the virus. However, these methods are less effective than growing resistant varieties and may have negative environmental impacts. Spraying of fungicides is not an effective method of controlling cassava mosaic virus because the disease is caused by a virus, not a fungus. Inoculation of the plant is also not a viable control strategy because it involves intentionally infecting the plant with the virus, which would only make the problem worse. Therefore, the correct answer is "growing resistant varieties."

Détails de la réponse

Détails de la réponse

The interval from the beginning of one heat period to the next is known as the "oestrus cycle." During this cycle, female animals experience a series of physiological changes in preparation for potential pregnancy. These changes include the release of hormones that trigger the growth and development of the follicles in the ovaries, which in turn lead to ovulation and the potential for fertilization. The oestrus cycle varies in length depending on the species, but it generally lasts from several days to several weeks. During this time, females exhibit physical and behavioral signs of being in heat, such as increased vocalizations, restlessness, and mounting behavior. These signs are typically used by farmers or animal breeders to determine the optimal time for breeding or artificial insemination. In summary, the interval from the beginning of one heat period to the next is known as the oestrus cycle, which is an important biological process in female animals that prepares them for potential pregnancy.

Détails de la réponse

The correct option is "increase in body size". Malnutrition is a condition in which an animal's diet is either deficient or excess in some essential nutrients needed for proper growth, maintenance, and reproduction. The general symptoms of malnutrition in animals include retarded growth, low production, susceptibility to diseases, and high mortality. These symptoms occur as a result of the animal's inability to obtain the necessary nutrients to sustain its normal metabolic functions. An increase in body size is not a symptom of malnutrition but rather an indication of overfeeding or obesity.

Détails de la réponse

Bone meal is the ingredient that is required for the formation of eggshell in poultry. Eggshells are primarily made of calcium carbonate, which is a mineral that is essential for the formation of strong and healthy eggshells. Bone meal is a source of calcium that is easily absorbed by the body, making it an important ingredient in poultry feed. Poultry require a regular supply of calcium to produce strong eggshells. If they do not get enough calcium in their diet, they may lay eggs with thin or weak shells, or even without shells at all. This can lead to problems such as broken or cracked eggs, reduced hatchability of eggs, and increased risk of infection. In summary, bone meal is an important ingredient in poultry feed because it provides the calcium that is necessary for the formation of strong and healthy eggshells.

Détails de la réponse

The item that should be checked daily before using a tractor is "engine oil". Engine oil is essential for lubricating the moving parts of a tractor's engine, which helps to reduce friction and prevent wear and tear. Without adequate oil, the engine can become damaged, which can lead to costly repairs and downtime. Therefore, it is important to check the engine oil level on a daily basis before using a tractor to ensure that it is at the recommended level. While the other items listed, such as the spark plug, distributor, air cleaner, and battery, are also important components of a tractor's engine and should be checked regularly, they do not necessarily need to be checked daily. The frequency of checking these items may vary depending on the tractor model, usage, and manufacturer's recommendations. In summary, engine oil should be checked daily before using a tractor to ensure that the engine is adequately lubricated and to prevent potential damage.

Détails de la réponse

Détails de la réponse

The problem that will not be considered before installing irrigation equipment in a farm is the build-up of pest and diseases. This is because the installation of irrigation equipment is solely for providing water to crops, and does not directly relate to the control of pests and diseases. The other options, on the other hand, are important considerations before installing irrigation equipment as they will impact the effectiveness and efficiency of the irrigation system. For instance, the cost of equipment and maintenance, source of power, availability of water, and concentration of salt in the water are all critical factors that need to be evaluated to ensure that the irrigation system is both functional and sustainable.

Détails de la réponse

Détails de la réponse

The gestation period of a cow, which is the length of time a cow carries a calf inside her body, is approximately 283 days. This means that it takes about 9 months for a cow to give birth to a calf. However, it is important to note that the gestation period can vary slightly depending on factors such as breed, age, and health of the cow.

Détails de la réponse

Détails de la réponse

Monocropping is not a way of maintaining soil fertility. Monocropping is a practice of growing only one type of crop on a piece of land repeatedly without rotating it with other crops. This practice can lead to soil degradation and nutrient depletion as the same nutrients are continuously extracted from the soil, and the land is susceptible to soil erosion and pests. On the other hand, cover cropping, manuring, mulching, and mixed farming are all effective ways of maintaining soil fertility. Cover cropping involves planting crops that cover the soil surface, which can help to improve soil structure and fertility, reduce soil erosion, and add organic matter to the soil. Manuring involves adding animal or plant waste to the soil, which can provide nutrients and improve soil structure. Mulching involves adding a layer of organic material to the soil surface, which helps to retain moisture, suppress weed growth, and improve soil fertility. Mixed farming involves growing different crops and/or raising animals on the same piece of land, which can help to maintain soil fertility by reducing soil erosion, diversifying nutrient inputs, and improving soil structure. In summary, while monocropping can lead to soil degradation and nutrient depletion, cover cropping, manuring, mulching, and mixed farming are all effective ways of maintaining soil fertility.

Détails de la réponse

Détails de la réponse

Détails de la réponse

Détails de la réponse

Détails de la réponse

The statement that crop rotation encourages the build-up of pests and diseases of crop is not correct. Crop rotation is a farming technique where different crops are planted in the same field over time, in a planned sequence. By alternating crops, the soil is less likely to become depleted of nutrients, which can help to maintain soil fertility. Additionally, crop rotation can reduce the buildup of pests and diseases that target specific crops, because pests and diseases that survive on one crop may not survive on another. This helps to protect the crops and ensure that they remain healthy. Furthermore, a good rotation system can also minimize exposure of soil to erosion and reduce infestation of land on rotation by weeds. Overall, crop rotation is an effective and sustainable method of farming that can benefit both the environment and farmers.

Détails de la réponse

Here's the text converted to HTML with important points bolded:
```html

(a) Two functions of a cultivator are:

1. To break up and loosen soil to prepare it for planting by removing weeds, rocks, and other debris. This helps to create a more suitable environment for crops to grow and flourish.

2. To mix in organic matter or fertilizers into the soil, which provides essential nutrients to crops and helps to improve soil fertility over time.

(b) Five tools or implements for each of the following farm processes are:

(i) Land preparation: Plow, disc harrow, rotavator, subsoiler, cultivator.

(ii) Planting: Seed drill, planter, dibber, transplanting machine, broadcast seeder.

(iii) Harvesting: Combine harvester, sickle, scythe, pruning shears, machete.

(iv) Crop processing: Thresher, winnower, grain dryer, rice mill, oil press.

(c) Four reasons why farmers cultivate small holdings are:

1. Food security: Cultivating small holdings can help to ensure that farmers have a reliable source of food for their families and local communities. By growing a variety of crops, farmers can also ensure that they have access to a diverse and nutritious diet.

2. Income generation: Small holdings can provide a source of income for farmers through the sale of crops and other agricultural products. This can help to support their families and improve their economic well-being.

3. Environmental sustainability: Small holdings can be managed using sustainable agricultural practices, which can help to conserve soil, water, and other natural resources. This can help to reduce the impact of farming on the environment and promote long-term ecological health.

4. Cultural heritage: Small holdings can also play an important role in preserving cultural heritage and traditional farming practices. By cultivating small plots of land using traditional methods, farmers can maintain and pass on important cultural knowledge and practices to future generations.

Détails de la réponse

(a) Cassava mosaic:

Symptoms:

1. Yellowing and mottling of leaves.
2. Stunted growth of the plant.

Control measures:

1. Use virus-free planting materials.
2. Remove and destroy infected plants.

(b) Groundnut rosette:

Symptoms:

1. Stunting of the plant.
2. Formation of rosettes, which are clusters of small, distorted leaves.

Control measures:

1. Plant resistant varieties.
2. Control aphid vectors, which can transmit the virus that causes the disease.

(c) Root-knot of okra:

Symptoms:

1. Galls or knots on the roots of the plant.
2. Yellowing and wilting of leaves.

Control measures:

1. Plant resistant varieties.
2. Rotate crops and use crop rotation practices.

(d) Bacterial blight of cotton:

Symptoms:

1. Water-soaked spots on leaves and stems.
2. Necrosis or death of infected plant tissues.

Control measures:

1. Use disease-free planting materials.
2. Apply copper-based fungicides to infected plants.

In summary, plant diseases such as cassava mosaic, groundnut rosettes, root-knot of okra, and bacterial blight of cotton can cause significant damage to crops. However, control measures such as the use of disease-free planting materials, plant rotation, and the use of resistant varieties, as well as the removal and destruction of infected plants, can help to manage and control the spread of these diseases.

Détails de la réponse

(a) Bush burning:

Bush burning involves the deliberate setting of fire to natural vegetation to clear land for farming. While this practice helps to clear land quickly, it can have negative effects on the soil. The intense heat from the fire can destroy organic matter, which is an essential component of healthy soil. It can also cause soil erosion and lead to the loss of nutrients, making it difficult for crops to grow.

(b) Overgrazing:

Overgrazing occurs when too many animals graze on a piece of land, leaving the vegetation depleted and the soil exposed. This practice can have detrimental effects on the soil as it leads to soil compaction and erosion. Overgrazing can also reduce soil fertility, making it difficult for plants to grow.

(c) Clean clearing:

Clean clearing involves the complete removal of all vegetation, including trees and bushes, from a piece of land. This practice can have negative effects on the soil as it leaves the soil exposed to erosion and can cause nutrient loss. It can also lead to a decrease in soil fertility, making it difficult for crops to grow.

(d) Fertilizer application:

Fertilizer application is a practice that involves adding essential nutrients to the soil to improve crop growth and yield. While this practice can have positive effects on the soil, such as improving soil fertility, it can also have negative effects if not done correctly. Overuse of fertilizers can lead to soil acidity, nutrient imbalances, and pollution of water sources. It can also lead to the buildup of salts in the soil, making it difficult for plants to grow.

Détails de la réponse

(a) Climatic and soil requirements: Tomato is a warm-weather crop that requires a temperature range of 20°C to 30°C to grow. It requires well-drained soils with a pH range of 6.0 to 7.0. The soil should be rich in organic matter and have good water holding capacity.

(b) Land preparation: The land for tomato cultivation should be well prepared by plowing, harrowing, and leveling the field. This ensures that the soil is well aerated and free of clods and weeds.

(c) Nursery practices: Tomato seeds are usually sown in a seedbed or nursery to raise seedlings. The seeds should be sown in trays or pots filled with a seed-starting mix. The seeds need to be watered regularly and kept in a warm, sunny location until they germinate.

(d) Planting and spacing: Once the seedlings have grown to a height of about 10-15cm, they can be transplanted to the main field. The tomato plants should be spaced at a distance of 45cm to 60cm between rows and 30cm to 45cm between plants.

(e) Fertilizer application: Tomato plants require balanced fertilization with nitrogen, phosphorus, and potassium. Fertilizers should be applied before planting and then every 2-3 weeks after transplanting. Nitrogen should be applied in smaller quantities during fruiting to avoid excessive vegetative growth.

(f) Staking: Tomato plants are usually staked to support their growth and prevent them from falling over. The stakes can be made of bamboo, wood, or metal. The tomato plants should be tied to the stakes using soft ties to avoid damage to the stems.

(g) Harvesting: Tomato plants usually start producing fruit 2-3 months after transplanting. The fruits should be harvested when they are fully ripe but still firm. Tomatoes should be picked regularly to encourage further fruit production. The harvested tomatoes should be handled carefully to avoid bruising and damage.

In summary, the production of tomatoes requires suitable climatic and soil conditions, proper land preparation, nursery practices, planting and spacing, fertilization, staking, and harvesting techniques. By following these steps, farmers can ensure the successful growth and development of tomato plants, leading to a healthy and bountiful harvest.

Détails de la réponse

(a)

1. Appreciation in agriculture refers to an increase in the value of an asset, such as land, livestock, or machinery. This can occur due to factors such as increased demand for a particular crop, improvements in infrastructure or technology, or natural resource depletion that makes land more scarce and valuable.
2. Depreciation in agriculture refers to a decrease in the value of an asset over time due to wear and tear, obsolescence, or other factors that reduce its usefulness or efficiency. This can be caused by factors such as age, inadequate maintenance, or changes in farming practices that make certain equipment or technology less relevant or useful.
3. Salvage value in agriculture refers to the estimated value of an asset at the end of its useful life. This value is based on factors such as the condition of the asset, market demand for similar assets, and other economic factors. Salvage value is used in calculating the depreciation of an asset over time.

(b)

1. The salvage value of the tractor is the amount for which it was sold when it was no longer useful for the farmer, which is N3,000.00.
2. The total depreciation of the tractor is the difference between its purchase price and its salvage value, which is N12,000.00 - N3,000.00 = N9,000.00.
3. The annual depreciation of the tractor is the total depreciation divided by the number of years the tractor was in use, which is (N12,000.00 - N3,000.00) / 9 = N1,000.00 per year.
4. There is no appreciation in this scenario because the value of the tractor decreased over time, from N12,000.00 to N3,000.00. Appreciation would occur if the value of the tractor had increased due to factors such as inflation or improvements in technology that made it more valuable over time.

Détails de la réponse

Here's the text converted to HTML with important points bolded:
```html

Agricultural extension plays several critical roles in the development of agriculture in Nigeria. Here are eight of them:

1. Technology transfer: Agricultural extension helps to transfer new technologies, best practices, and innovations to farmers to improve their productivity and income.

2. Education and training: Extension workers provide education and training to farmers on various aspects of agriculture, such as crop production, livestock management, soil fertility, and pest control.

3. Research and development: Extension workers are involved in research and development activities to identify and address the challenges facing farmers and to develop new technologies and practices that can improve agricultural production.

4. Market development: Extension workers assist farmers in identifying market opportunities and developing marketing strategies to increase their income from agriculture.

5. Networking: Extension workers facilitate networking among farmers, input suppliers, agribusinesses, and other stakeholders to promote collaboration and knowledge sharing.

6. Advisory services: Extension workers provide advisory services to farmers on issues related to production, marketing, finance, and other aspects of agricultural development.

7. Policy advocacy: Extension workers advocate for policies and programs that promote agricultural development and support the needs of farmers.

8. Climate change adaptation: Extension workers help farmers to adapt to the impacts of climate change by promoting climate-smart agriculture practices and providing information on climate risk management.

In summary, agricultural extension is critical to the development of agriculture in Nigeria, and its roles are diverse and encompass several aspects of agricultural development.

Détails de la réponse

a) Rock weathering:

Rock weathering refers to the process by which rocks are broken down into smaller pieces and eventually into soil over time, due to the action of physical, chemical, and biological agents.

b) Four factors affecting soil formation:

1. Parent material: The type of rock from which the soil is formed determines its mineral content and physical properties.
2. Climate: Temperature, rainfall, and humidity affect the rate of weathering and the types of vegetation that can grow in a particular region, which in turn influences the type of soil that is formed.
3. Topography: The slope, aspect, and elevation of a landscape affect the amount of water and sunlight that soil receives, as well as its exposure to erosion.
4. Time: The longer a soil has been forming, the more mature it becomes, with more layers and greater diversity of organisms.

c) Four types of chemical weathering:

1. Hydrolysis: This is the chemical reaction between minerals in rocks and water. Water reacts with minerals in the rock, causing them to break down into smaller, more soluble compounds.
2. Oxidation: This is the reaction between oxygen and minerals in rocks, such as iron, which can result in the formation of rust. This process can weaken the structure of rocks and make them more susceptible to physical weathering.
3. Carbonation: This is the reaction between carbon dioxide in the atmosphere and minerals in rocks, particularly calcium carbonate. This reaction can lead to the dissolution of minerals in the rock and the formation of karst landscapes.
4. Acidification: This is the reaction between acidic substances, such as acid rain or plant roots, and minerals in rocks. Acidification can dissolve minerals in the rock and lead to the formation of caves and sinkholes.

Summary:

In summary, rock weathering is the process by which rocks are broken down into soil over time. Factors that affect the formation of soil include parent material, climate, topography, and time. Chemical weathering includes hydrolysis, oxidation, carbonation, and acidification, each of which can cause the breakdown of minerals in rocks and contribute to the formation of soil.

Détails de la réponse

(a) Four methods of harvesting fish include:

1. Seine netting: This involves the use of a large net with weights at the bottom and floats at the top. The net is drawn through the water by boats or pulled onto shore, capturing fish in the process.
2. Trawling: This involves towing a large net behind a boat through the water. The net is designed to catch fish by entrapping them in its mesh as it moves through the water.
3. Longlining: This involves the use of a long line with baited hooks that are set at intervals along the line. The line is then dropped into the water and left to sit for a period of time before being retrieved, along with any fish that have been caught.
4. Gill netting: This involves the use of a net with small mesh size that hangs vertically in the water. Fish swim into the net and become entangled in the mesh.

(b) Four fishery regulations include:

1. Size limits: Regulations that specify minimum or maximum size of fish that can be caught and kept. These limits help to protect young or mature fish from being caught before they have had a chance to breed.
2. Bag limits: Regulations that limit the number of fish that can be caught and kept by an individual or group of individuals. These limits help to prevent overfishing and ensure that fish populations remain healthy.
3. Seasonal closures: Regulations that specify times of the year when fishing is prohibited. These closures help to protect fish during critical periods of their life cycle, such as spawning or migration.
4. Fishing gear restrictions: Regulations that limit the types of gear that can be used for fishing in certain areas. These restrictions help to prevent damage to marine habitats and reduce bycatch of non-target species.

Détails de la réponse

a) Eight functions of water in livestock management include:

1. Regulating body temperature: Water helps regulate body temperature by enabling sweating and panting, which dissipates heat from the body.
2. Transporting nutrients: Water is a key component of blood and other bodily fluids, which transport nutrients and oxygen to cells throughout the body.
3. Aiding digestion: Water is essential for digestion and helps move food through the digestive tract.
4. Lubricating joints: Water is a component of synovial fluid, which lubricates joints and reduces friction.
5. Flushing waste products: Water helps remove waste products, such as urine and feces, from the body.
6. Maintaining hydration: Water is essential for maintaining proper hydration levels in animals, which is necessary for overall health and wellbeing.
7. Supporting milk production: Lactating animals require more water to support milk production.
8. Supporting growth: Water is necessary for cellular growth and repair, which is especially important for young animals.

b) Eight essential mineral elements required in animal nutrition are:

1. Calcium
2. Phosphorus
3. Magnesium
4. Sodium
5. Chloride
6. Potassium
7. Iron
8. Zinc

c) Four functions of mineral elements in the body of animals are:

1. Structural support: Minerals such as calcium and phosphorus are important for bone formation and maintenance.
2. Enzyme function: Many minerals, such as iron and zinc, are essential components of enzymes, which catalyze biochemical reactions in the body.
3. Nerve and muscle function: Minerals such as sodium and potassium are important for nerve and muscle function, including transmitting nerve signals and contracting muscles.
4. Fluid balance: Minerals such as sodium and chloride help maintain proper fluid balance in the body, which is necessary for cellular function and overall health.

Détails de la réponse

(a) Finance: One of the major problems of agricultural development in Nigeria is lack of adequate finance. Many farmers in Nigeria lack access to finance, which limits their ability to invest in modern farming techniques, purchase quality inputs, and improve their yields. This makes it difficult for farmers to expand their production and earn higher incomes. The lack of finance also limits the ability of agricultural companies to invest in research and development, which can lead to the development of better farming techniques and inputs.

(b) Farm input: Another factor that contributes to the problems of agricultural development in Nigeria is the lack of quality farm inputs. Many farmers in Nigeria use outdated and low-quality farming inputs, such as seeds, fertilizers, and pesticides. This leads to low productivity and poor crop yields. Additionally, the high cost of quality farm inputs makes it difficult for farmers to access and use them.

(c) Transportation: Transportation is another major problem of agricultural development in Nigeria. The poor state of the transportation system, especially rural roads, makes it difficult for farmers to transport their products to markets. This often results in post-harvest losses, as perishable crops such as fruits and vegetables are unable to reach the markets in time. The high cost of transportation also reduces the profitability of farming, as farmers have to pay high prices to transport their products.

(d) Storage and processing facilities: Lack of proper storage and processing facilities is also a problem of agricultural development in Nigeria. Many farmers do not have access to proper storage facilities, which leads to post-harvest losses due to spoilage and insect infestation. Additionally, the lack of processing facilities limits the ability of farmers to add value to their products, which reduces their profitability. This limits the ability of farmers to earn higher incomes and reinvest in their farming activities.

In conclusion, finance, farm input, transportation, and storage and processing facilities are some of the major factors that contribute to the problems of agricultural development in Nigeria. Addressing these challenges will require significant investments in infrastructure, research and development, and policy reforms to support the growth of the agricultural sector.