2022 WAEC (WASSCE) Agricultural Science Past Questions and Answers
The 2022 WAEC (WASSCE) Agricultural Science past questions with answers: 47 objective questions from the 2022 paper in the DeeepSolve question bank, each with its answer behind "Show answer". Try each question before you check, then practise the paper as a timed WAEC-style CBT.
Past questions © the examination body (JAMB/WAEC/NECO). DeeepSolve is not affiliated with them. Rights holders: see /copyright.
Questions
- 1.
Which of the following groups of crops will thrive in areas with high rainfall?
- A.Cotton, cowpea and groundnut
- B.Millet, maize and cotton
- C.Guinea com, cowpea and maize
- D.Cocoa, oil palm and rubber
Show answer
Answer: D. Cocoa, oil palm and rubber
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
2.This question needs a diagram, table or passage that we don't have yet, so it isn't shown.
- 3.
Capping is a cultural practice carried out in the cultivation of
- A.carrot
- B.cassava
- C.potato
- D.yam
Show answer
Answer: D. yam
AI explanation
Analyze the question: The question asks which crop has "capping" as a cultural practice.
Explain the concept: Capping in Nigerian agriculture is not the same as pruning or earthing up. It usually refers to covering newly planted yam heads or mounds, or covering planted yam setts, with materials like dry grass, palm fronds, or straw. This is done after planting yam setts on mounds or ridges.
Why it is done:
- It protects the setts from direct sunlight and excessive heat.
- It prevents heavy rain from washing away the soil or waterlogging the sett.
- It conserves soil moisture.
- It helps the setts sprout properly.
Checking the options:
- A. Carrot: Grown from seed on a seedbed. Thinning and weeding are the usual practices, not capping.
- B. Cassava: Propagated by stem cuttings, planted flat, slanted, or upright. No capping.
- C. Potato: Sweet or Irish potato involves earthing up or ridging, not capping.
- D. Yam: Setts are planted on mounds or ridges and then capped with grass or palm fronds, so this is a yam practice.
Answer: The correct option is D, yam.
Tip: Remember "Yam = mound, stake, cap." Yam practices include mounding, staking, and capping (covering the mound), which together make it distinct from other root and tuber crops.
AI can make mistakes. Report anything that looks wrong.
4.This question needs a diagram, table or passage that we don't have yet, so it isn't shown.
- 5.
The diagram below illustrates a farm implement. Use it to answer this question. The function of the part labelled II is to
- A.remove soil
- B.turn soil
- C.break clods
- D.cut stumps
Show answer
Answer: C. break clods
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 6.
Monocotyledonous crops include
- A.oil palm, rice, and plantain.
- B.cowpea, pepper and tomato
- C.garden egg, cassava and mango
- D.rubber, cashew and orange
Show answer
Answer: A. oil palm, rice, and plantain.
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 7.
The practice of placing the correct number of seeds in the soil with definite intra-row and inter-row spacing is called
- A.seed drilling
- B.centrifugal distribution
- C.precision planting
- D.seed broadcasting
Show answer
Answer: C. precision planting
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 8.
The main reason for castrating farm animals is to
- A.remove male odour
- B.make the animal sterile
- C.increase meat production
- D.make them lose weight
Show answer
Answer: B. make the animal sterile
AI explanation
Step 1: Analyze the question The question asks for the main reason farmers castrate (remove or disable the testes of) male farm animals such as bulls, rams, bucks and boars.
Step 2: Explain the concept Castration is a management practice in livestock production. It is done mainly to:
- Control breeding, so that only selected superior males reproduce (prevents indiscriminate mating and inbreeding)
- Make animals docile and easier to handle
- Improve meat quality (reducing "boar taint" or strong male odour)
- Prevent unwanted pregnancies in the herd
Castrated males are called steers (cattle), wethers (sheep and goats) and barrows (pigs).
Step 3: Evaluate the options
- A. Remove male odour: This is a real benefit, especially in pigs and goats, but it is a secondary effect.
- B. Make the animal sterile: Castration removes the ability to reproduce. This is the direct and defining effect, and the basis for controlling breeding. It is the main reason.
- C. Increase meat production: Castrates may fatten more easily and give tender meat, but this is not the primary purpose. Intact males often grow faster because of testosterone.
- D. Make them lose weight: Incorrect. Castration usually promotes fat deposition rather than weight loss.
Step 4: Answer The main reason is to render the animal sterile, which gives the farmer control over breeding.
Tip: In WASSCE Agric Science, when asked for the "main" reason for castration, think of the direct result: no testes = no breeding = sterility. Other benefits such as docility and meat quality are side advantages.
AI can make mistakes. Report anything that looks wrong.
- 9.
A by-product of all livestock is
- A.hide
- B.horn
- C.milk
- D.meat
Show answer
Answer: A. hide
AI explanation
Analyze the question: We need something obtained from all livestock (cattle, goats, sheep, pigs, poultry, rabbits, etc.) as a by-product, meaning a secondary product obtained in addition to the main product.
Explain the concept:
- A primary product is the main reason the animal is raised, such as meat, milk or eggs.
- A by-product is a secondary material obtained from the animal, usually after slaughter, such as hides and skins, horns, hooves, bones, blood, feathers and fat.
Check each option:
- A. Hide: Every slaughtered animal has a covering (hide or skin) that can be used for leather, drums, bags and shoes. In Nigerian agriculture, "hides and skins" are classic by-products. Even though poultry have feathers and pigs have skin, the idea of a covering (hide/skin) applies broadly to livestock.
- B. Horn: Only some animals have horns (cattle, goats, sheep). Pigs, poultry and rabbits do not, so it is not common to all.
- C. Milk: Only female mammals produce milk for human use, and it is a primary product rather than a by-product. Poultry do not produce milk.
- D. Meat: Meat is the primary product of livestock, not a by-product.
Answer: Hide is the best choice.
Tip: Remember the rule "primary products = meat, milk, eggs; by-products = hides, horns, hooves, bones, blood, feathers." If a question asks for something common to all livestock, choose the by-product that every animal has, such as the hide or skin, and avoid features that only some animals have, such as horns.
AI can make mistakes. Report anything that looks wrong.
- 10.
A difference between physical and chemical weathering is that
- A.there is a change in the mineral composition of rock in physical weathering
- B.the mineral composition of rock is changed in chemical weathering.
- C.carbonation is necessary in physical weathering.
- D.wind is necessary in chemical weathering.
Show answer
Answer: B. the mineral composition of rock is changed in chemical weathering.
AI explanation
Step 1: Analyze the question The question asks for a difference between physical and chemical weathering.
Step 2: The concept
- Physical (mechanical) weathering breaks rock into smaller pieces without changing its mineral composition. Examples are temperature changes (expansion and contraction), frost action, abrasion by wind and water, and root action.
- Chemical weathering breaks down rock through chemical reactions that change the minerals into new substances. Examples are hydrolysis, oxidation, hydration, solution, and carbonation.
Step 3: Check each option
- A. Wrong. Physical weathering does not change mineral composition. It only reduces particle size.
- B. Correct. Chemical weathering changes the mineral composition of the rock. For example, feldspar changes to clay through hydrolysis, and iron minerals change to iron oxides through oxidation.
- C. Wrong. Carbonation (carbon dioxide dissolving in water to form weak carbonic acid) is a chemical process, not a physical one.
- D. Wrong. Wind is an agent of physical weathering (abrasion). Chemical weathering needs water and dissolved gases, not wind.
Step 4: Answer
Exam tip: Remember "Physical = size changes, Chemical = substance changes." If an option says the minerals are altered, it is describing chemical weathering. Also, any process ending in "-ation" such as carbonation, oxidation, or hydration is chemical.
AI can make mistakes. Report anything that looks wrong.
- 11.
Decomposition of soil organic matter is mainly caused by
- A.bacteria
- B.algae
- C.fungi
- D.nematodes
Show answer
Answer: A. bacteria
AI explanation
Step 1: Analyze the question The question asks which organisms are mainly responsible for breaking down (decomposing) organic matter in the soil, such as dead plants, animal remains, and manure.
Step 2: Explain the concept Decomposition is the breakdown of complex organic materials into simpler substances (humus, CO₂, water, and mineral nutrients) that plants can use. The main decomposers are soil microorganisms, which feed on dead organic material:
- Bacteria: the most numerous soil microorganisms. They are extremely abundant (millions to billions per gram of soil), reproduce quickly, and carry out most of the decomposition and nutrient cycling (e.g., ammonification and nitrification).
- Fungi: also important decomposers, especially of tough materials like lignin and cellulose in woody matter and in acidic soils. In most standard textbooks, however, bacteria are given as the main agents.
- Algae: mostly photosynthetic organisms. They make their own food, so they are not decomposers.
- Nematodes: microscopic roundworms. Some are parasites of plants (e.g., root-knot nematodes), and others feed on bacteria or fungi. They are not the main decomposers.
Step 3: Eliminate the options
- B (algae): they photosynthesize, so they are ruled out.
- D (nematodes): many are pests or just feeders on microbes, so they are ruled out.
- Between A and C: both decompose, but bacteria are the most abundant and active, so they are regarded as the main cause in the WASSCE syllabus.
Step 4: Answer The correct option is **A.
Tip: Think "BActeria = BAsic decomposers", the most numerous and fastest at breaking down organic matter. Remember that algae make food (like plants), and nematodes are mostly known as pests in Agricultural Science questions.
AI can make mistakes. Report anything that looks wrong.
- 12.
Damping of disease of tomato could be controlled by
- A.staking
- B.supplying
- C.thinning
- D.pruning
Show answer
Answer: C. thinning
AI explanation
Analyze the question: Damping-off is a fungal disease (caused by Pythium, Rhizoctonia, Phytophthora) that attacks seedlings in the nursery. It causes the stem base to rot and the seedlings to collapse and die. It is favoured by overcrowding, excess moisture, poor air circulation and high humidity.
Explain the concept: Control measures include:
- Sowing seeds thinly, and thinning out overcrowded seedlings
- Avoiding overwatering and ensuring good drainage
- Using sterilized soil
- Treating seeds with fungicides
- Providing good aeration and light
Evaluate the options:
- A. Staking – Giving support to tall crops like tomato with sticks. This keeps the plants off the ground, but it is done to mature plants and does not address seedling damping-off.
- B. Supplying – Replacing seedlings that failed to germinate or died. This is a replacement practice, not a control measure.
- C. Thinning – Removing excess seedlings to reduce overcrowding. This improves air circulation and lowers humidity around the seedlings, which reduces the spread of the fungus. This is the best fit.
- D. Pruning – Removing unwanted branches or shoots from mature plants. It is not aimed at nursery seedling diseases.
Answer: Thinning reduces overcrowding in the nursery and so helps to control damping-off.
Exam tip: Link the keywords: damping-off = seedlings = nursery = overcrowding and moisture. Any option that reduces crowding or excess moisture (such as thinning, or proper spacing) is usually the answer. Staking and pruning are for older plants, and supplying is just replacement of dead stands.
AI can make mistakes. Report anything that looks wrong.
13.This question needs a diagram, table or passage that we don't have yet, so it isn't shown.
- 14.
Which of the following farm animals will browse more on plants in a pasture?
- A.Goats
- B.Cattle
- C.Pigs
- D.Sheep
Show answer
Answer: A. Goats
AI explanation
Step 1: Analyze the question The question asks which animal browses most. "Browsing" means feeding on leaves, twigs, shoots and young stems of shrubs and trees. This is different from "grazing," which means feeding on grasses and low-growing herbage.
Step 2: Explain the concept
- Grazers mainly eat grass. Cattle and sheep are typical grazers.
- Browsers prefer shrubs, tree leaves and woody plants. Goats are the classic example.
- Pigs are omnivores. They root in the soil and eat roots, tubers, grains and household waste, so they are not typical pasture browsers.
Step 3: Work through the options
- A. Goats: They are selective feeders. They stand on their hind legs, reach for leaves and twigs, and prefer shrubs and tree foliage to grass. They are the most common browsers.
- B. Cattle: They use their tongues to pull in grass, so they are mainly grazers.
- C. Pigs: They are monogastric omnivores and do not graze or browse much.
- D. Sheep: They have a split upper lip and graze close to the ground, so they are grazers.
Step 4: Answer Goats browse more on plants in a pasture.
Exam tip: Remember "Goats Browse, Cattle and Sheep Graze." Both start with a "G" sound for grass and goat, but goats are the exception because they choose leaves and shrubs. If a question says "browse," think of goats first.
AI can make mistakes. Report anything that looks wrong.
- 15.
Soil-borne diseases could be controlled in the nursery by
- A.mulching
- B.manuring
- C.heat treatment
- D.provision of shade
Show answer
Answer: C. heat treatment
AI explanation
Step 1: Analyze the question The question asks how soil-borne diseases (diseases caused by pathogens living in the soil, such as fungi, bacteria, nematodes) can be controlled in a nursery.
Step 2: Explain the concept In a nursery, seedlings are raised in beds or containers filled with soil. If the soil carries pathogens (e.g., damping-off fungi), the seedlings will be infected. The best control is soil sterilization, which means killing the pathogens before sowing. This can be done by:
- Heat treatment (steaming or baking the soil, or burning dry grass or trash on the bed)
- Chemical treatment (fumigation)
Step 3: Evaluate the options
- A. Mulching: Covers the soil to conserve moisture, control weeds, and moderate temperature. It does not kill pathogens.
- B. Manuring: Adds nutrients to the soil. It does not control disease.
- C. Heat treatment: Kills fungi, bacteria, nematodes, and weed seeds in the soil. This directly controls soil-borne diseases.
- D. Provision of shade: Protects seedlings from excess sun and heat. It does not eliminate soil pathogens.
Step 4: Answer The correct option is C. heat treatment.
Tip: When you see "soil-borne" in a question, think sterilization, which means heat or chemicals. Remember: soil-borne disease, so treat the soil with heat.
AI can make mistakes. Report anything that looks wrong.
- 16.
Ranging poles used in farm surveying have characteristic
- A.green and white bands
- B.blue and white bands
- C.red and white bands
- D.black and red bands
Show answer
Answer: C. red and white bands
AI explanation
Analyze the question: The question asks about the colour pattern of ranging poles used in farm (land) surveying.
Concept: A ranging pole (or ranging rod) is a straight pole about 2 m long (sometimes up to 3 m). It is used to mark points and to establish straight lines (ranging) on the ground during surveying. The pole is painted in alternating bands, usually red and white (sometimes black and white, or red and yellow), so that it is clearly visible from a distance against different backgrounds such as grass, soil, or bush. The lower end is fitted with a pointed metal shoe so it can be pushed into the ground.
Going through the options:
- A. Green and white: green would blend into vegetation on a farm, so it is not used.
- B. Blue and white: this is not the standard surveying colour combination.
- C. Red and white: this is the standard combination, with high contrast and good visibility.
- D. Black and red: this is not the standard pairing. Black and white is sometimes used, but black and red is not typical.
Answer: The correct option is C. red and white bands.
Tip: Think of a ranging pole as a "traffic-warning" stick. Red and white stand out strongly, so they are easy to see from far away. Remember "Red-White for sight."
AI can make mistakes. Report anything that looks wrong.
- 17.
Removal of needle teeth is important in the management of
- A.kids
- B.lambs
- C.calves
- D.piglets
Show answer
Answer: D. piglets
AI explanation
Analyze the question: The question asks which young animal needs its "needle teeth" removed as part of management.
Concept: Newborn piglets are born with eight sharp, needle-like teeth, called needle teeth. There are four on each side, in the upper and lower jaws. They are clipped (or ground down) within the first 24 hours after birth for these reasons:
- They can injure the sow's udder and teats while the piglets suckle. This makes the sow reluctant to nurse and can lead to mastitis.
- Piglets fighting for teats can cut each other's faces.
- Wounds from the teeth can become infected.
Step-by-step solution:
- Kids (young goats): they are not born with needle teeth. Their management includes disbudding and castration.
- Lambs (young sheep): the main practices are docking and castration, not clipping teeth.
- Calves (young cattle): the main practices are dehorning/disbudding and navel treatment.
- Piglets (young pigs): needle teeth clipping, iron injection, tail docking and castration. Needle teeth clipping belongs here.
Answer: The correct option is D, piglets.
Exam tip: Match each animal with its signature practice:
- Piglets → needle teeth clipping and iron injection
- Calves → dehorning
- Lambs → docking
- Kids → disbudding
"Needle" is sharp, and so are piglets' teeth, so think of pigs whenever you see it.
AI can make mistakes. Report anything that looks wrong.
- 18.
If 200 layers require 25 kg of layer mash per day, calculate the quantity of feed required by 1,000 layers per day.
- A.5kg
- B.40kg
- C.80kg
- D.125kg
Show answer
Answer: D. 125kg
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 19.
Which of the following statements about silage are true? I. It has a laxative effect II. is acidic in reaction. III. has a strong aroma when well prepared
- A.I and II only
- B.I and III only
- C.II and III only
- D.I, II and III
Show answer
Answer: D. I, II and III
AI explanation
Analyze the question: You are asked which statements about silage are true. Silage is green fodder preserved by anaerobic fermentation in a silo.
Explain the concept: When green fodder is packed tightly and sealed, bacteria ferment the plant sugars into organic acids, mainly lactic acid. The acids lower the pH and preserve the feed.
Check each statement:
- I. It has a laxative effect: TRUE. Silage is succulent and has high moisture. Feeding it fresh and in large amounts makes the animal's dung loose, so it acts as a mild laxative.
- II. It is acidic in reaction: TRUE. Fermentation produces lactic and acetic acids. Good silage has a pH of about 3.5 to 4.5.
- III. It has a strong aroma when well prepared: TRUE. Well-made silage has a pleasant, sweet-sour smell that is strong and distinct. This also makes it palatable to livestock. Poorly made silage smells rotten or putrid.
All three statements are true, so the answer is I, II and III.
Correct option: D
Exam tip: Remember silage as "Sour, Smelly, Succulent":
- Sour means acidic.
- Smelly means a pleasant, strong aroma when well made.
- Succulent means juicy and mildly laxative.
When all the statements sound like standard silage properties, check whether "all of the above" fits before eliminating options.
AI can make mistakes. Report anything that looks wrong.
- 20.
The most common way of controlling weeds in tree crop plantations is by
- A.crop rotation
- B.hand pulling
- C.flooding
- D.slashing
Show answer
Answer: D. slashing
AI explanation
Step 1: Analyze the question The question asks for the most common method of weed control in tree crop plantations (e.g., cocoa, oil palm, rubber, orange, coffee). Think about the scale and the type of crop.
Step 2: Explain the concept Weed control methods must suit the crop and the size of the farm:
- Crop rotation: Works for annual or arable crops, where different crops are grown in turns on the same land. Tree crops are perennial and stay on the land for many years, so rotation is not practical.
- Hand pulling: Effective, but it is slow and tiring. It suits small gardens, nurseries, and young seedlings, not large plantations.
- Flooding: Used mainly in rice fields, where standing water suppresses weeds. It would damage or kill most tree crops.
- Slashing: Cutting weeds with a cutlass or a mower. It is cheap, quick, and easy over large areas. It does not disturb the roots of the trees, which tend to be shallow in crops like cocoa. This is why it is the common practice in plantations.
Step 3: Work through the options
- A: Not suitable for perennial tree crops. ❌
- B: Too laborious for large plantations. ❌
- C: Would harm tree crops. ❌
- D: Practical, cheap, and widely used in plantations. ✅
Step 4: Answer The correct option is D. slashing.
Tip: Link each method to its crop type. Remember: flooding goes with rice, rotation goes with arable crops, hand pulling goes with small gardens or nurseries, and slashing goes with plantations.
AI can make mistakes. Report anything that looks wrong.
- 21.
The correct order of arrangement of ration for piglets from day old is
- A.weaners >growers->creep > finisher.
- B.creep>weaners>growers>finisher.
- C.growers>finisher>creep>weaners.
- D.finishers>creep>weaners>growers
Show answer
Answer: B. creep>weaners>growers>finisher.
AI explanation
Analyze the question: It asks for the correct sequence of feeds given to pigs from the day they are born until they are ready for market.
Concept: Pigs are fed different rations at different stages of growth, because their nutritional needs change as they grow:
- Creep feed – Given to suckling piglets from about 1-2 weeks old until weaning. It is high in protein and highly digestible, and it supplements the sow's milk.
- Weaner ration – Given after the piglets are weaned (about 6-8 weeks old).
- Grower ration – Given to young pigs growing rapidly (about 10-12 weeks until about 60 kg).
- Finisher ration – Given last, until the pig reaches market weight. It is higher in energy and lower in protein.
Solution: The order is therefore:
Creep → Weaner → Grower → Finisher
Checking the options:
- A starts with weaners and puts creep third. Wrong.
- B: creep > weaners > growers > finisher. Correct.
- C starts with growers. Wrong.
- D starts with finishers. Wrong.
Exam tip: Remember the order with the phrase "C-W-G-F" ("Come With Good Food"): Creep, Weaner, Grower, Finisher. The ration follows the pig's age: the youngest animal gets the first feed, and the oldest gets the finisher.
AI can make mistakes. Report anything that looks wrong.
- 22.
Use the information below to answer this question. In an experiment on soil porosity, the following results were obtained: Volume of dry soil = 52cm³ Volume of water= 48cm³ Volume of soil and water=78cm³ Calculate the porosity of the soil sample
- A.28.21%
- B.42.31%
- C.45.83%
- D.61.54%
Show answer
Answer: B. 42.31%
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 23.
If maize seeds are sown at a spacing of 60 cm by 90 cm, what is the plant population of maize expected on one hectare of farmland?
- A.18,519 plants
- B.16,667 plants
- C.11,111 plants
- D.5,400 plants
Show answer
Answer: A. 18,519 plants
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
24.This question needs a diagram, table or passage that we don't have yet, so it isn't shown.
- 25.
To reduce rural-urban migration, the government should
- A.establish commodity boards
- B.provide social infrastructure
- C.establish tractor-hiring units
- D.provide extension services to farmers
Show answer
Answer: B. provide social infrastructure
AI explanation
Step 1: Analyze the question The question asks what the government can do to reduce rural-urban migration, which is the movement of people (especially youths) from villages to cities.
Step 2: Understand the concept People leave rural areas mainly because of the "push factors": lack of good roads, electricity, pipe-borne water, hospitals, schools, and recreation. They are drawn to cities by the "pull factors", which are these same amenities plus job opportunities. To keep people in rural areas, the government must make rural life more attractive and comfortable.
Step 3: Evaluate the options
- A. Establish commodity boards: These stabilize prices and market farm produce. They help farmers' incomes, but they do not directly address the poor living conditions that push people out.
- B. Provide social infrastructure: Roads, electricity, water, schools, and health centres directly remove the push factors. This is the most direct and widely accepted solution.
- C. Establish tractor-hiring units: These help with farm mechanization, but they only affect farmers and do not improve general living conditions.
- D. Provide extension services: These pass improved farming knowledge to farmers. This is useful for productivity, but it is not the main cause of migration.
Step 4: Answer It tackles the root cause of migration by making rural areas livable.
Exam tip: When you see "rural-urban migration" in questions, think "amenities". Remember the phrase "Make the village comfortable and the youths will stay." Social infrastructure (roads, light, water, hospitals, schools) is usually the key answer.
AI can make mistakes. Report anything that looks wrong.
26.This question needs a diagram, table or passage that we don't have yet, so it isn't shown.
- 27.
The diagram below illustrates a tool used to analyse a soil sample in an experiment. Use it to answer this question. The aim of the experiment is to determine the soil
- A.structure
- B.texture
- C.mineral matter
- D.organic matter
Show answer
Answer: D. organic matter
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 28.
Which of the following crops is correctly matched with a disease that affects it?
- A.Maize - smut
- B.Sorghum - scab
- C.Rice- black arm
- D.Yam- blast
Show answer
Answer: A. Maize - smut
AI explanation
Step 1: Analyze the question We need the crop-disease pair that is correct. Let's check each one.
Step 2: Check each option
- A. Maize - smut: Correct. Maize (corn) smut is caused by the fungus Ustilago maydis. It produces swollen, grey-black galls on the ears, tassels and stalks.
- B. Sorghum - scab: Scab is a disease of wheat and barley (Fusarium head blight), and of cowpea/citrus (in other forms). Sorghum's well-known diseases are smut (grain smut, head smut), ergot, anthracnose and downy mildew.
- C. Rice - black arm: Black arm (angular leaf spot) is a bacterial disease of cotton, caused by Xanthomonas. Rice diseases include blast, brown spot and bacterial leaf blight.
- D. Yam - blast: Blast is a disease of rice (Magnaporthe oryzae). Yam diseases include anthracnose, yam mosaic virus, and tuber rot.
Step 3: Answer Only option A is a correct match.
Tip: Memorize the classic pairings:
- Maize → smut, rust, streak
- Rice → blast
- Cotton → black arm
- Cocoa → black pod, swollen shoot
- Cassava → mosaic, bacterial blight
- Yam → anthracnose, tuber rot
Black arm = cotton, blast = rice. These are common WASSCE traps.
AI can make mistakes. Report anything that looks wrong.
- 29.
The diagram below illustrates the digestive system of a farm animal. Use it to answer this question. The part labelled lll is the
- A.pancreas
- B.caecum
- C.small intestine
- D.large intestine
Show answer
Answer: C. small intestine
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 30.
The gross profit of a farm business is the farm's
- A.net sales less cost of production.
- B.total sales less operating expenses.
- C.net sales less taxation.
- D.total sales less cost of production.
Show answer
Answer: D. total sales less cost of production.
AI explanation
Analyze the question: It asks for the definition of gross profit in a farm business.
Concept: Gross profit is the profit made from the core production activity, before the overhead and other running costs are subtracted. In accounting terms:
Gross profit = Total sales (revenue) − Cost of production (cost of goods sold)
Other related terms:
- Net profit = Gross profit − Operating (overhead) expenses, and then taxes and other deductions.
- Gross margin in farm management is similar: total revenue less the variable (direct production) costs.
Check each option:
- A. Net sales less cost of production: "Net sales" means sales after returns and discounts. This is used in some accounting texts, but the standard textbook definition in WASSCE Agricultural Science uses total sales. This is less precise.
- B. Total sales less operating expenses: Subtracting operating expenses leads toward net profit, not gross profit. This is wrong.
- C. Net sales less taxation: Deducting tax gives a profit after tax, which is not gross profit. This is wrong.
- D. Total sales less cost of production: This matches the standard definition of gross profit. This is correct.
Tip: Remember the order of profit: Gross profit comes first (sales − cost of production), then net profit comes after you subtract operating expenses and taxes. "Gross" is the bigger figure, before the extra deductions.
AI can make mistakes. Report anything that looks wrong.
- 31.
Swampy lands are most suitable for growing
- A.yam
- B.rice
- C.maize
- D.tomato
Show answer
Answer: B. rice
AI explanation
Analyze the question: The question asks which crop grows best on swampy land, meaning land that is waterlogged or saturated for much of the year.
Concept: Crops differ in how well they tolerate water around their roots.
- Most arable crops need well-drained soil. Their roots need oxygen, and waterlogging causes root rot and poor growth.
- Rice is the exception. It is a semi-aquatic crop. Its stems have air spaces (aerenchyma tissue) that carry oxygen down to the roots, so it can grow in flooded fields. This is why rice is grown in swamps, fadama lands and inland valleys, for example in Niger, Ebonyi, Kebbi and Benue States.
Step-by-step solution:
- A. Yam: It needs well-drained soil, usually planted on mounds or ridges. Waterlogging rots the tubers. Not suitable.
- B. Rice: It thrives in waterlogged or flooded conditions. Suitable.
- C. Maize: It needs well-drained fertile soil and is sensitive to waterlogging. Not suitable.
- D. Tomato: It needs well-drained soil, and wet soil encourages wilt and fungal diseases. Not suitable.
Answer: The correct option is B. rice.
Exam tip: Link "swamp, waterlogged, fadama, flooded" with rice. Link "well-drained soil" with yam, maize, tomato, cassava and most other arable crops.
AI can make mistakes. Report anything that looks wrong.
- 32.
Lactation normally occurs
- A.at the onset of conception
- B.at the onset of puberty
- C.after gestation.
- D.after mating
Show answer
Answer: C. after gestation.
AI explanation
Analyze the question: The question asks when lactation (milk production by the mammary glands) normally begins in farm animals such as cattle, goats, sheep and pigs.
Explain the concept:
- Gestation is the pregnancy period, from conception to birth (parturition).
- Lactation is the secretion of milk by the mammary glands. Hormones such as prolactin and oxytocin drive it. Prolactin stimulates milk production, and oxytocin causes milk let-down.
- During pregnancy, estrogen and progesterone develop the mammary glands but hold back full milk secretion. At birth, progesterone drops, prolactin takes over, and milk production starts. This is why a cow only gives milk after she has calved.
Step-by-step evaluation of the options:
- A. At the onset of conception: Incorrect. At conception the animal has only just become pregnant, and the mammary glands are not yet ready to produce milk.
- B. At the onset of puberty: Incorrect. Puberty is when the animal becomes sexually mature. It does not trigger milk production.
- C. After gestation: Correct. Lactation begins after the young one is born, once the gestation period ends.
- D. After mating: Incorrect. Mating may lead to conception, but milk production only starts after the pregnancy is completed.
Answer: C. After gestation.
Exam tip: Remember the sequence Mating → Conception → Gestation → Parturition → Lactation. Lactation always comes after birth. Think of a cow: no calf, no milk!
AI can make mistakes. Report anything that looks wrong.
33.This question needs a diagram, table or passage that we don't have yet, so it isn't shown.
- 34.
Use the information below to answer this question. I. Yellowing of leaves II. Raised brown spots on the leaves III. Drying up of leaves IV. Exudation of gum The disease of citrus described above is
- A.die-back
- B.gummosis
- C.tristeza
- D.blight
Show answer
Answer: B. gummosis
AI explanation
Step 1: Analyze the question We are given four symptoms of a citrus disease: yellowing of leaves, raised brown spots on leaves, drying up of leaves, and exudation of gum. We need to match them to the correct disease.
Step 2: Review the concepts
- Die-back: Starts at the tips of twigs and branches, which die progressively backward. It is often caused by nutrient deficiency (e.g. copper) or fungi. The key sign is dying twigs and branches, not gum.
- Gummosis: Caused by Phytophthora fungi. The key sign is the oozing of gum from the trunk and branches, along with bark cracking. The leaves yellow and dry up because the tree's water and nutrient flow is disrupted.
- Tristeza: A viral disease spread by aphids. Signs are vein clearing, stunted growth, stem pitting and quick decline. There is no gum exudation.
- Blight: A general term for rapid leaf and tissue death. It is not specifically linked to gum exudation in citrus.
Step 3: Match the symptoms
- Yellowing of leaves: consistent with gummosis, as the tree's vascular flow is damaged.
- Raised brown spots on leaves: consistent with lesions and cankers on the tree.
- Drying up of leaves: a result of the disrupted flow of water.
- Exudation of gum: the most distinctive sign, and it points directly to gummosis.
Step 4: Answer The exudation of gum is the giveaway symptom. The disease is gummosis, which is option B.
Exam tip: Look for the name inside the symptom. "Gum" exudation means gum-osis. Also remember: die-back means twigs dying from the tip, and tristeza means a virus spread by aphids.
AI can make mistakes. Report anything that looks wrong.
- 35.
Water can be conserved in the soil by
- A.mulching, strip cropping and cover cropping
- B.weeding, strip cropping and clean clearing
- C.clean clearing, mulching, and strip cropping
- D.cover cropping, mulching and weeding
Show answer
Answer: A. mulching, strip cropping and cover cropping
AI explanation
Analyze the question: The question asks which practices help conserve (retain) water in the soil. Practices that reduce evaporation, runoff, and exposure of bare soil are the ones that conserve moisture.
Explain the concepts:
- Mulching: Covering the soil with dry grass, straw, or leaves reduces evaporation and keeps the soil cool and moist. ✔
- Cover cropping: Growing low-spreading crops (e.g., melon, sweet potato, legumes) shades the soil, reduces evaporation, and slows runoff. ✔
- Strip cropping: Planting different crops in alternating strips across a slope reduces runoff speed so more water soaks into the soil. ✔
- Weeding: Removing weeds reduces competition for water, but it does not directly conserve soil water. It is not a conservation practice in this sense.
- Clean clearing: Removing all vegetation leaves the soil bare, which increases evaporation, runoff, and erosion. ✘
Step-by-step elimination:
- B includes weeding and clean clearing. Clean clearing is harmful to soil moisture, so B is out.
- C includes clean clearing, so C is out.
- D includes weeding. Mulching and cover cropping are good, but weeding is not a water-conserving practice, so D is weaker.
- A contains mulching, strip cropping, and cover cropping. All three conserve soil water.
Exam tip: In conservation questions, spot the "bad" practice first. Words like clean clearing, bush burning, and overgrazing usually expose the wrong options. Remember that anything that covers the soil (mulch, cover crops) or slows runoff (strips, terraces, contour ridges) conserves water.
AI can make mistakes. Report anything that looks wrong.
36.This question needs a diagram, table or passage that we don't have yet, so it isn't shown.
- 37.
A non-governmental organization involved in agricultural development in West Africa is
- A.Operation Feed the Nation
- B.River Basin Development Authority
- C.Agricultural Development Project
- D.International Institute of Tropical Agriculture
Show answer
Answer: D. International Institute of Tropical Agriculture
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 38.
Potassium deficiency in cereal crops Is indicated by
- A.browning of leaves Trom the tips and margins
- B.yellowing of younger leaves
- C.purpling of leaves
- D.white and irregular spots on leaves
Show answer
Answer: A. browning of leaves Trom the tips and margins
AI explanation
Step 1: Analyze the question The question asks which symptom shows potassium (K) deficiency in cereal crops such as maize, rice, and millet.
Step 2: Concept Potassium is a mobile nutrient in the plant. When it is in short supply, the plant moves it from older leaves to younger growing parts. So the symptoms show first on the older (lower) leaves. Potassium helps with water regulation, enzyme activation, and strong stalks.
Typical potassium deficiency signs:
- Yellowing, then browning (scorching) of leaf tips and margins, starting on older leaves
- Weak stalks, so the crop lodges (falls over) easily
- Poor grain filling
Step 3: Check each option
- A. Browning of leaves from the tips and margins: This is the classic sign of potassium deficiency (leaf scorch). ✔
- B. Yellowing of younger leaves: This points to immobile nutrient deficiencies such as iron, sulphur, or calcium. Nitrogen deficiency yellows the older leaves first. ✘
- C. Purpling of leaves: This is typical of phosphorus deficiency. ✘
- D. White and irregular spots on leaves: This suggests deficiencies such as zinc ("white bud" in maize) or a disease problem, not potassium. ✘
Step 4: Answer The correct option is A.
Exam tip: Remember the pairing:
- N: yellowing of older leaves (V-shaped in maize)
- P: purple leaves
- K: scorched, brown leaf edges and tips
- Zn: white or pale bands and spots
- Fe: yellowing of young leaves
AI can make mistakes. Report anything that looks wrong.
- 39.
The diagram below illustrates a farm implement. Use it to answer this question. The illustrated farm implement i used for
- A.pulverizing soil into fine tilth
- B.breaking up soil into clods
- C.gathering top soil
- D.levelling soil surface
Show answer
Answer: B. breaking up soil into clods
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
40.This question needs a diagram, table or passage that we don't have yet, so it isn't shown.
- 41.
Salt licks are provided for grazing animals to
- A.make the pasture palatable.
- B.supply nutrients in pastures
- C.supplement mineral intake
- D.provide laxatives
Show answer
Answer: C. supplement mineral intake
AI explanation
Step 1: Analyze the question The question asks why farmers provide salt licks (blocks of salt, often with added minerals) for grazing animals such as cattle, sheep and goats.
Step 2: Explain the concept Pasture grasses, especially in tropical areas like Nigeria, are often low in some minerals, particularly sodium and chlorine (the elements in common salt, NaCl). Grazing animals need these minerals for:
- Nerve and muscle function
- Maintaining body fluid balance
- Digestion and appetite
- Growth, milk production and reproduction
A salt lick is placed where animals can lick it freely. This supplements the minerals they cannot get in sufficient quantities from pasture alone.
Step 3: Evaluate each option
- A. Make the pasture palatable. Wrong. Salt licks are given to the animals directly and do not change the taste of the pasture.
- B. Supply nutrients in pastures. Wrong. This describes fertilizing or improving pasture (for example, planting legumes). Salt licks are not applied to the pasture.
- C. Supplement mineral intake. Correct. Salt licks add the sodium, chlorine and sometimes trace minerals (iodine, cobalt, etc.) that the pasture lacks.
- D. Provide laxatives. Wrong. Salt licks are not given to relieve constipation.
Step 4: Answer The correct option is **C.
Exam tip: Remember the keyword pair: salt lick = mineral supplement. When you see "lick" in an Agricultural Science question, think of minerals, not pasture improvement or medicine.
AI can make mistakes. Report anything that looks wrong.
- 42.
The main factors responsible for rock weathering in the desert are high temperature and
- A.animal activity
- B.water
- C.wind
- D.root growth
Show answer
Answer: C. wind
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 43.
Use the information below to answer this question. In an experiment on soil porosity, the following results were obtained: Volume of dry soil = 52cm³ Volume of water= 48cm³ Volume of soil and water=78cm³ Determine the volume of airspace in the soil sample.
- A.22cm³
- B.26cm³
- C.30cm³
- D.100cm³
Show answer
Answer: A. 22cm³
AI explanation
Analyze the question: This is the classic experiment where water is poured onto a known volume of dry soil. The air spaces (pores) in the soil are displaced by the water, so the total volume ends up smaller than the sum of the two separate volumes.
Concept: Volume of air space = (Volume of dry soil + Volume of water) − Volume of soil and water together
The "missing" volume is the air that escaped as the water filled the pores.
Solution:
- Volume of dry soil = 52 cm³
- Volume of water added = 48 cm³
- Sum = 52 + 48 = 100 cm³
- Volume of soil and water after mixing = 78 cm³
Volume of air space = 100 − 78 = 22 cm³
Check: The air space is 22 cm³, so the porosity is 22/52 × 100 ≈ 42%, which is a reasonable value for a soil.
Correct answer: A (22 cm³).
Option D (100 cm³) is just the sum of the two volumes, which is a common trap. Options B and C do not come from any correct step.
Exam tip: In soil porosity questions, always subtract the final combined volume from the sum of the individual volumes. Remember: "Add first, then subtract the final reading, and what is left is the air."
AI can make mistakes. Report anything that looks wrong.
- 44.
In farming enterprise, short term loans are used to
- A.purchase farm machinery
- B.construct new farm buildings
- C.construct an irrigation dam
- D.purchase agrochemicals
Show answer
Answer: D. purchase agrochemicals
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 45.
A combine harvester can be used simultaneously to harvest
- A.legumes and apply fertilizer
- B.grains and eradicate weeds
- C.tubers and distribute fertilizer
- D.cereals and winnow grains
Show answer
Answer: D. cereals and winnow grains
AI explanation
Analyze the question: The question asks what a combine harvester does at the same time (simultaneously) during harvesting.
Explain the concept: The name "combine" comes from the fact that the machine combines several harvesting operations into one pass:
- Reaping – cutting the standing crop
- Threshing – separating the grains from the stalks and husks
- Winnowing – blowing away the chaff (light, unwanted material) from the grains
- Collecting – storing the clean grain in a tank
It is used mainly for cereals such as rice, maize, wheat, millet, and sorghum.
Solution (checking each option):
- A. Legumes and apply fertilizer: Applying fertilizer is not a harvesting operation. Wrong.
- B. Grains and eradicate weeds: Weed control is done with herbicides or cultivators, not by a combine harvester. Wrong.
- C. Tubers and distribute fertilizer: Tubers (yam, cassava) are harvested with tuber harvesters or diggers, and fertilizer distribution is a separate operation. Wrong.
- D. Cereals and winnow grains: A combine harvests cereals and, in the same pass, threshes and winnows the grains. Correct.
Answer: D. Cereals and winnow grains.
Exam tip: Remember that "combine" means combining reaping, threshing, and winnowing in one machine. If an option mentions fertilizer or weeding, it's not a harvesting job, so eliminate it.
AI can make mistakes. Report anything that looks wrong.
- 46.
The establishment of cooperative farming is encouraged by governments because it
- A.enables farmers to control soil erosion
- B.facilitates the use of hand tools
- C.enables individual farmers to acquire capital
- D.allows farmers to cultivate small and scattered plots
Show answer
Answer: C. enables individual farmers to acquire capital
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app
- 47.
Nitrogen is important in plants because it is mainly needed in
- A.fruit formation
- B.root development
- C.leaf formation
- D.cell division
Show answer
Answer: C. leaf formation
Get a step-by-step AI explanation in the appGet a step-by-step AI explanation in the app