WAEC Agricultural Science 2021 past questions and answers

The branch of crop science which deals with the study of insect pests is

1. A.zoology.
2. B.agronomy
3. C.entomology.
4. D.pathology.

Horse racing and polo are events where horses are used for

1. A.wildlife conservation.
2. B.recreation.
3. C.dowry payment.
4. D.transportation.

The construction of rural feeder roads solves the following access problems in agriculture except

1. A.marketing.
2. B.transportation.
3. C.extension services.
4. D.land tenure system.

The diagram below illustrates a farm tool.
The illustrated farm tool is used for

1. A.making mounds.
2. B.transplanting seedlings.
3. C.cutting trees
4. D.pruning hedges.

The diagram below illustrates a farm tool.
The farm implement that could perform a similar function as the illustrated tool is

1. A.plough.
2. B.harrow.
3. C.ridger.
4. D.cultivator.

A tractor-mounted sprayer used on large-scale farms is the

1. A.electrodyne sprayer.
2. B.motorized sprayer.
3. C.knapsack sprayer.
4. D.boom sprayer.

Which of the following types of farm power does not cause pollution?

1. A.Hydro
2. B.Electrical
3. C.Mechanical
4. D.Chemical

In planning a farmstead, the structure which should be located on high elevation is the

1. A.fish pond.
2. B.pigsty.
3. C.farmhouse.
4. D.processing shed.

The diagram below illustrates processes in the water cycle.
The process labelled I is

1. A.evaporation.
2. B.absorption.
3. C.respiration
4. D.transpiration.

The diagram below illustrates processes in the water cycle.
The process labelled II is

1. A.transpiration.
2. B.condensation
3. C.evaporation.
4. D.respiration.

The diagram below illustrates processes in the water cycle.
The major source of water to the plants in the diagram is

1. A.gravitational water.
2. B.hygroscopic water
3. C.capillary water.
4. D.surface water.

The new rock formed when limestone is subjected to great heat and pressure is

1. A.slate
2. B.graphite
3. C.marble
4. D.gneiss.

Which of the following pairs of raw materials is used in the canning industry?

1. A.Meat and fish
2. B.Cotton and tea
3. C.Hide and skin
4. D.pulpwood and cocoa

Microorganisms that decompose organic matter will function best under

1. A.waterlogged soil condition.
2. B.anaerobic soil condition
3. C.low soil temperature
4. D.optimum soil pH.

In an experiment to determine the percentage of organic matter in a soil sample, the following data was collected: weight of oven-dried soil before burning = 50g. Weight of oven-dried soil after burning = 28g
Calculate the weight of organic matter in the soil.

1. A.11g
2. B.22g
3. C.44g
4. D.78g

In an experiment to determine the percentage of organic matter in a soil sample, the following data was collected: weight of oven-dried soil before burning = 50g. Weight of oven-dried soil after burning = 28g
Determine the percentage of organic matter in the soil.

1. A.22%
2. B.44%
3. C.56%
4. D.60%

Which of the following practices will improve clay soil?

1. A.Use of acid-forming fertilizers
2. B.Bush burning
3. C.Addition of sodium chloride
4. D.Addition of organic material

A farmer practices crop rotation in order to

1. A.reduce yield.
2. B.improve soil texture
3. C.increase pest incidence
4. D.improve soil fertility.

The phosphorus cycle is described as being sedimentary because phosphorus

1. A.is a macroelement.
2. B.is an earthbound element.
3. C.is solid at room temperature.
4. D.occurs in the atmosphere.

The following factors are essential for maize production except

1. A.high temperature
2. B.low temperature
3. C.relative humidity
4. D.adequate rainfall.

Drying of newly harvested grains before storage helps to increase the

1. A.moisture content.
2. B.pest incidence.
3. C.seed viability.
4. D.nutrient content.

Yams stored in a barn should be inspected at least once a week in order to

1. A.remove irregular shaped tubers.
2. B.control termite attack.
3. C.prevent mouldiness in yam.
4. D.remove sprouts and rotten tubers.

The botanical name of onion is

1. A.Zea mays.
2. B.Oryza sativa.
3. C.Carica papaya
4. D.Allium cepa.

Okro seeds are sown on 0.72 hectares of farmland at a spacing of 60 cm by 60 cm. Calculate the expected plant population.

1. A.3,600 plants
2. B.7,200 plants
3. C.10,000 plants
4. D.20,000 plants

A plot of land devoted to the cultivation of fruit trees is called

1. A.orchard.
2. B.farmstead.
3. C.forest.
4. D.ranch.

Two species of kola grown for commercial purposes in West Africa are

1. A.cola acuminata and cola gigantea
2. B.cola nitida and cola verticillata
3. C.cola nitida and cola acuminata
4. D.cola verticillata and cola gigantea

Propagation of ginger is generally done using its

1. A.corm.
2. B.rhizome.
3. C.sucker.
4. D.seed.

Elaeis guineensis and Arachis hypogaea are examples of

1. A.latex crops.
2. B.oil crops.
3. C.fibre crops
4. D.fruit crops

The diagram below illustrates a farm operation.
Which of the following statements is not a reason for carrying out the illustrated farm operation? To

1. A.expose the leaves to sunlight.
2. B.prevent damage by rodents.
3. C.improve the yield of the crop
4. D.prevent lodging of the plants.

The diagram below illustrates a farm operation.
Crops which require the illustrated farm operation are

1. A.yam and cowpea.
2. B.tomato and okro.
3. C.okro and pepper.
4. D.tomato and yam.

The basic importance of agriculture to a forester is to

1. A.obtain honey.
2. B.obtain food
3. C.acquire labour.
4. D.procure timber.

A suitable grass for lawns is

1. A.Andropogon gayanus.
2. B.pennisetum purpureum.
3. C.cynodon dactylon
4. D.panicum maximum.

The causative organism of maize rust is a

1. A.bacterium
2. B.protozoon.
3. C.virus.
4. D.fungus.

Which of the following groups of insect pests damage crops by biting and chewing?

1. A.Cotton stainer, armyworm and cricket.
2. B.Cricket, mealybug and whitefly
3. C.Armyworm, termite and grasshopper
4. D.Cotton stainer, mealybug and termite

The breeds of cattle resistant to trypanosomiasis are

1. A.N'dama and Muturu.
2. B.White Fulani and Biu.
3. C.Red Bororo and Adamawa.
4. D.Wadara and Sokoto Gudali.

Which of the following features is not a characteristics of a good layer?

1. A.Bright red comb and wattle
2. B.Long and curved beak
3. C.Bright and bulging eyes
4. D.Broad and flexible pelvic bone

The best way for a young animal to obtain colostrum is by

1. A.giving it powdered milk.
2. B.providing it with warm milk.
3. C.injecting it with progesterone.
4. D.allowing it to suckle the dam.

If 0.7 kg of feed was fed to chicks per week, determine the cost of feeding the birds for 6 weeks. (1 kg of feed cost N5)

1. A.N4.20
2. B.N11.70
3. C.N21.00
4. D.N30.00

Feeds that have more than 18% fibre are classified as

1. A.concentrates.
2. B.additives.
3. C.supplements.
4. D.roughages.

An advantage of zero-grazing is that it

1. A.requires a lot of labour.
2. B.prevents livestock from physical exercises.
3. C.prevents depletion of pasture.
4. D.increases the cost of pasture management.

The diagram below illustrates a tool used in animal production.
The illustrated tool is

1. A.an elastrator
2. B.a burdizzo
3. C.an electric dehorner.
4. D.an artificial vagina.

The diagram below illustrates a tool used in animal production.
The illustrated tool is used for

1. A.castrating the bull calf
2. B.cutting the horns of the animal
3. C.collecting semen from the bull
4. D.identifying the animal.

Formation of blisters on the mouth and the skin around the hoof of farm animals is a symptom of

1. A.rinderpest.
2. B.anthrax.
3. C.Newcastle disease.
4. D.foot and mouth disease.

In sheep production, tapeworm could be controlled by

1. A.dusting.
2. B.spraying.
3. C.dipping.
4. D.drenching.

The table below illustrates the supply schedule for maize.
Price (N) 24 — Quantity supplied 480 kg
Price (N) 16 — Quantity supplied 400 kg
The percentage change in quantity supplied for maize is

1. A.16.7%.
2. B.20%.
3. C.80%.
4. D.83.3%.

The table below illustrates the supply schedule for maize.
Price (N) 24 — Quantity supplied 480 kg
Price (N) 16 — Quantity supplied 400 kg
Calculate the percentage change in price for maize.

1. A.8.0%
2. B.33.3%
3. C.50.0%
4. D.66.7%

The table below illustrates the supply schedule for maize.
Price (N) 24 — Quantity supplied 480 kg
Price (N) 16 — Quantity supplied 400 kg
Determine the elasticity of supply for maize.

1. A.0.3
2. B.0.4
3. C.0.5
4. D.0.6

A long term loan for an agricultural enterprise could be obtained from

1. A.microfinance banks.
2. B.commercial banks.
3. C.money lenders
4. D.cooperative societies.

Which of the following problems of agriculture could be solved through farmers' adoption of research findings?

1. A.Unpredictable climate
2. B.Environmental degradation
3. C.Poor extension services
4. D.Insufficient basic amenities

(a) Mention two roles of the governments of West African countries in agricultural development in each of the following areas: (i) agricultural finance; (ii) agricultural education; (iii) agricultural extension services; (iv) agricultural policies and programmes.
(b) State three structural differences between disc plough and disc harrow. (Use a table with the columns: Disc plough, Disc harrow.)
(c) Highlight four effects of the frequent use of disc plough on the soil.

(a) Explain three roles played by each of the following factors in soil formation: (i) time; (ii) rainfall; (iii) parent material.
(b) Mention four principles which should be followed in a good crop rotation plan.
(c) Give five uses of forage crops.

(a)(i) Explain the term selective exploitation as used in forest management. (ii) State four advantages of selective exploitation of forest trees.
(b) Distinguish between field pests and storage pest of crops.
(c) Name three examples each of: (i) storage insect pests of crops; (ii) field insect pests of crops.
(d) Mention four ways of conserving water in the soil.

(a) Give four reasons why each of the following farm operations is important: (i) pruning of cocoa trees; (ii) parboiling of paddy rice.
(b) A farmer abandoned a plot of land due to low soil fertility. After three years, it was discovered that guinea grass has invaded the land. Suggest five ways by which the farmer can eradicate the grass.
(c) State five uses of ornamental plants.

A farmer fed some lambs with eight different feed compositions. Assuming the Feed Conversion Ratio (FCR) = Feed intake (g) ÷ Weight gain (g)
(a) Complete the table below.
(b) Deduce from the table the feed with the; (i) highest feed conversion ratio; (ii) lowest feed conversion ratio;
(c) Name five products that could be obtained from farm animals.
(d) List three chemical processes involved in rock weathering.

(a) An outbreak of Avian influenza was reported in a locality with the possibility of the disease spreading to other parts of the country. (i) Mention three main agricultural extension methods that could be used to create awareness of the disease among poultry farmers. (ii) Which of the main agricultural extension methods mentioned in 6(a)(i) is most appropriate to create awareness among poultry farmers? (iii) Give two reasons for the choice of the extension methods mentioned in 6(a)(ii). (iv) Mention three problems that could be encountered in the use of the extension method mentioned in 6(a)(ii).
(b) Highlight five problems faced by farm managers.
(c) Name four breeds of goat found in West Africa.