Junior Certificate Examination
Agricultural Science
Q1501.
What is the main purpose of applying a mulch layer around young trees?
A
Increase soil compaction
B
Reduce soil temperature fluctuations
C
Increase pest attraction
D
Decrease water infiltration
Correct Answer: B
Mulch stabilises soil temperature, reduces evaporation, and suppresses weeds.
Junior Certificate Examination
Agricultural Science
Q1502.
Which of the following best describes the concept of "sustainable yield" in forestry?
A
Cutting all trees annually
B
Harvesting at a rate that replenishes the forest
C
Planting only fast-growing species
D
Removing all understory vegetation
Correct Answer: B
Sustainable yield ensures the forest can regenerate and continue to provide resources.
Junior Certificate Examination
Agricultural Science
Q1503.
Which of the following is a direct effect of soil compaction on plant roots?
A
Increased oxygen availability
B
Enhanced root elongation
C
Restricted root expansion
D
Improved nutrient uptake
Correct Answer: C
Compacted soils limit root growth and reduce aeration, harming plant development.
Junior Certificate Examination
Agricultural Science
Q1504.
Which of the following is NOT a typical symptom of nitrogen deficiency in leafy vegetables?
A
Interveinal chlorosis
B
Stunted growth
C
Dark green leaves
D
Reduced leaf expansion
Correct Answer: C
Dark green leaves are a sign of excess nitrogen, not deficiency.
Junior Certificate Examination
Agricultural Science
Q1505.
In the process of composting, which phase is characterized by rapid heat generation and microbial activity?
A
Mesophilic phase
B
Thermophilic phase
C
Cooling phase
D
Maturation phase
Correct Answer: B
The thermophilic phase sees high temperatures due to active decomposition.
Junior Certificate Examination
Agricultural Science
Q1506.
Which of the following is an example of a non‑renewable resource used in agriculture?
A
Solar energy
B
Wind power
C
Fossil fuel for machinery
D
Biogas
Correct Answer: C
Fossil fuels are non-renewable and contribute to greenhouse gas emissions.
Junior Certificate Examination
Agricultural Science
Q1507.
Which of the following best explains the term "soil erosion"?
A
The accumulation of organic matter in soil
B
The loss of topsoil by wind or water
C
The increase in soil pH over time
D
The process of soil compaction
Correct Answer: B
Soil erosion removes fertile topsoil, reducing land productivity.
Junior Certificate Examination
Agricultural Science
Q1508.
In a greenhouse, which of the following gases is most important to monitor for plant health?
A
Oxygen
B
Nitrogen
C
Carbon dioxide
D
Chlorine
Correct Answer: C
CO₂ levels influence photosynthetic rates and growth.
Junior Certificate Examination
Agricultural Science
Q1509.
Which of the following is a primary advantage of using biochar in soil amendment?
A
Increase soil acidity
B
Reduce soil microbial activity
C
Enhance water retention and nutrient holding capacity
D
Decrease soil organic matter
Correct Answer: C
Biochar improves soil structure, water retention, and nutrient availability.
Junior Certificate Examination
Agricultural Science
Q1510.
What is the main reason for using cover crops during fallow periods?
A
To increase soil salinity
B
To suppress weeds and improve soil structure
C
To reduce organic matter
D
To increase pest populations
Correct Answer: B
Cover crops prevent erosion, fix nitrogen, and improve soil health.
Junior Certificate Examination
Agricultural Science
Q1511.
Which of the following is a key component of an agroforestry system?
A
Monoculture plantations
B
Integration of trees with crops or livestock
C
Exclusive use of chemical fertilizers
D
Complete removal of native vegetation
Correct Answer: B
Agroforestry combines trees with other agricultural practices for ecological benefits.
Junior Certificate Examination
Agricultural Science
Q1512.
In the context of climate change, which of the following practices can help reduce the carbon footprint of a farm?
A
Increase irrigation frequency
B
Expand monoculture fields
C
Implement precision agriculture techniques
D
Use high‑yield synthetic fertilizers only
Correct Answer: C
Precision agriculture optimises inputs, reducing waste and emissions.
Junior Certificate Examination
Agricultural Science
Q1513.
Which of the following best describes the primary function of the root system in a plant?
A
To conduct photosynthesis
B
To absorb water and nutrients from the soil
C
To store carbohydrates for later use
D
To protect the plant from herbivores
Correct Answer: B
Roots primarily absorb water and essential minerals from the soil to support plant growth.
Junior Certificate Examination
Agricultural Science
Q1514.
In crop rotation, what is the main advantage of including legumes in the sequence?
A
They increase soil acidity
B
They provide shade for other crops
C
They fix atmospheric nitrogen into the soil
D
They reduce the need for irrigation
Correct Answer: C
Legumes host Rhizobium bacteria that convert atmospheric nitrogen into a form usable by plants, enriching soil fertility.
Junior Certificate Examination
Agricultural Science
Q1515.
Which of the following is NOT a characteristic of a good irrigation water source for crops?
A
Low salinity
B
High pH
C
Adequate flow rate
D
Low temperature
Correct Answer: B
High pH can limit nutrient availability; good irrigation water should have a neutral to slightly acidic pH.
Junior Certificate Examination
Agricultural Science
Q1516.
The term "biomass" in agricultural science refers to:
A
The total amount of soil organic matter
B
The total mass of living organisms in a given area
C
The mass of all crops harvested in a season
D
The amount of water stored in a field
Correct Answer: B
Biomass is the total mass of all living organisms in a specific ecosystem at a given time.
Junior Certificate Examination
Agricultural Science
Q1517.
Which of the following practices is most effective in preventing soil erosion on sloping farmland?
A
Increasing fertilizer application
B
Planting cover crops and using contour ploughing
C
Removing all vegetation for better sunlight
D
Using heavy machinery during the rainy season
Correct Answer: B
Cover crops and contour ploughing reduce runoff and protect the soil surface.
Junior Certificate Examination
Agricultural Science
Q1518.
Which of the following diseases is caused by a fungal pathogen that attacks the roots of maize?
A
Yellow leaf spot
B
Root rot
C
Stem rust
D
Leaf blight
Correct Answer: B
Root rot is a fungal disease that infects the root system, reducing water uptake.
Junior Certificate Examination
Agricultural Science
Q1519.
Which of the following is a key component of integrated pest management (IPM)?
A
Exclusive use of chemical pesticides
B
Use of genetically modified crops only
C
Combining biological, cultural, and chemical methods
D
Ignoring pest monitoring until damage is visible
Correct Answer: C
IPM relies on multiple strategies to control pests sustainably.
Junior Certificate Examination
Agricultural Science
Q1520.
In the context of soil fertility, what does "soil organic matter" primarily contribute?
A
Structural stability and water retention
B
Direct nitrogen supply to plants
C
A source of heavy metals
D
Increased soil acidity
Correct Answer: A
Organic matter improves soil structure, aeration, and moisture holding capacity.
Junior Certificate Examination
Agricultural Science
Q1521.
Which of the following best describes the process of photosynthesis?
A
Conversion of water into oxygen by roots
B
Conversion of sunlight into chemical energy in chloroplasts
C
Storage of carbohydrates in stems
D
Absorption of nitrogen from the soil
Correct Answer: B
Photosynthesis occurs in chloroplasts, converting light energy into glucose.
Junior Certificate Examination
Agricultural Science
Q1522.
What is the main function of the stomata in a leaf?
A
To transport sugars to roots
B
To regulate gas exchange and transpiration
C
To store water for the plant
D
To produce chlorophyll
Correct Answer: B
Stomata open and close to allow CO₂ in for photosynthesis and release O₂ and water vapor.
Junior Certificate Examination
Agricultural Science
Q1523.
Which of the following is an example of a perennial crop?
A
Wheat
B
Potato
C
Sugarcane
D
Corn
Correct Answer: C
Sugarcane is a perennial plant that can be harvested multiple times from the same root system.
Junior Certificate Examination
Agricultural Science
Q1524.
Which soil testing parameter is most directly related to plant-available phosphorus?
A
Soil pH
B
Cation exchange capacity
C
Phosphate concentration in soil extract
D
Organic matter percentage
Correct Answer: C
Phosphate concentration in a soil extract indicates the amount of phosphorus accessible to plants.
Junior Certificate Examination
Agricultural Science
Q1525.
What is the primary benefit of using mulches in crop production?
A
Increase soil salinity
B
Reduce soil temperature fluctuations and moisture loss
C
Increase weed seed germination
D
Promote rapid leaf senescence
Correct Answer: B
Mulches help maintain soil moisture, regulate temperature, and suppress weeds.
Junior Certificate Examination
Agricultural Science
Q1526.
Which of the following is a characteristic of a "sustainable" agricultural practice?
A
Maximising yield at the expense of soil health
B
Using only synthetic chemicals
C
Maintaining ecological balance while producing food
D
Ignoring local farming traditions
Correct Answer: C
Sustainable agriculture seeks to balance productivity with ecological stewardship.
Junior Certificate Examination
Agricultural Science
Q1527.
What is the main role of nitrogen-fixing bacteria in legumes?
A
Increase soil pH
B
Convert atmospheric nitrogen into ammonium usable by plants
C
Provide potassium to the plant
D
Reduce water uptake
Correct Answer: B
Rhizobium bacteria convert N₂ gas into ammonium (NH₄⁺), enriching soil nitrogen.
Junior Certificate Examination
Agricultural Science
Q1528.
Which of the following best explains the term "yield gap"?
A
The difference between theoretical maximum yield and actual yield
B
The time between planting and harvest
C
The amount of fertilizer needed per hectare
D
The number of pests per plant
Correct Answer: A
Yield gap is the discrepancy between potential and realized crop yields.
Junior Certificate Examination
Agricultural Science
Q1529.
In crop breeding, what does "heterosis" refer to?
A
The reduction of genetic diversity
B
The increased vigor of hybrid offspring compared to parents
C
The process of mutagenesis
D
The selection of drought-tolerant varieties only
Correct Answer: B
Heterosis, or hybrid vigor, results in hybrids that outperform parent lines in growth or yield.
Junior Certificate Examination
Agricultural Science
Q1530.
Which of the following is a primary source of energy for plant metabolic processes?
A
Soil nutrients
B
Sunlight
C
Atmospheric CO₂
D
Root exudates
Correct Answer: B
Sunlight provides the energy required for photosynthesis and other metabolic reactions.
Junior Certificate Examination
Agricultural Science
Q1531.
What is the main advantage of using drip irrigation over conventional flood irrigation?
A
Higher water usage
B
Uniform distribution across large areas
C
Reduced water loss due to evaporation and runoff
D
Simpler installation
Correct Answer: C
Drip irrigation delivers water directly to the root zone, minimizing losses.
Junior Certificate Examination
Agricultural Science
Q1532.
Which of the following is a common symptom of potassium deficiency in plants?
A
Yellowing of leaf tips and margins
B
Stunted root growth
C
Excessive leaf growth
D
Rapid flowering
Correct Answer: A
Potassium deficiency often causes interveinal chlorosis, especially at leaf edges.
Junior Certificate Examination
Agricultural Science
Q1533.
In the context of pest management, what does "biological control" involve?
A
Use of chemical pesticides only
B
Introduction of natural predators or pathogens to suppress pest populations
C
Complete crop rotation with unrelated species
D
Irrigation with saltwater
Correct Answer: B
Biological control employs living organisms to keep pest numbers in check.
Junior Certificate Examination
Agricultural Science
Q1534.
Which of the following is a characteristic of a "no-till" farming system?
A
Frequent ploughing to loosen soil
B
Direct seeding without tillage, preserving soil structure
C
Use of heavy machinery every season
D
Removal of all crop residues before planting
Correct Answer: B
No-till farming reduces soil disturbance, improving structure and reducing erosion.
Junior Certificate Examination
Agricultural Science
Q1535.
Which of the following best describes a "cover crop"?
A
A crop grown for its high market value
B
A crop planted to protect and enrich the soil when no cash crop is grown
C
A crop that is harvested before the main crop
D
A genetically engineered crop with pest resistance
Correct Answer: B
Cover crops are planted mainly for soil conservation and fertility enhancement.
Junior Certificate Examination
Agricultural Science
Q1536.
What is the primary function of the cuticle layer on plant leaves?
A
To absorb water
B
To reduce water loss through transpiration
C
To provide structural support
D
To attract pollinators
Correct Answer: B
The waxy cuticle reduces transpiration and protects against environmental stress.
Junior Certificate Examination
Agricultural Science
Q1537.
Which of the following best explains "soil compaction"?
A
Increase in soil organic matter
B
Reduction in pore space due to pressure, limiting root growth
C
Increase in soil pH
D
Decrease in soil salinity
Correct Answer: B
Compacted soil has fewer pores, restricting root expansion and water infiltration.
Junior Certificate Examination
Agricultural Science
Q1538.
What is the main reason for applying mulch after planting seedlings?
A
To increase soil temperature dramatically
B
To provide a source of nitrogen
C
To suppress weed growth and conserve moisture
D
To encourage rapid leaf senescence
Correct Answer: C
Mulch helps control weeds, maintain moisture, and moderate soil temperature.
Junior Certificate Examination
Agricultural Science
Q1539.
Which of the following is a key indicator of plant water stress?
A
Increased leaf chlorophyll content
B
Stomatal closure and reduced transpiration
C
Rapid root elongation
D
Enhanced fruit set
Correct Answer: B
Water stress causes stomata to close, reducing transpiration and photosynthesis.
Junior Certificate Examination
Agricultural Science
Q1540.
In a greenhouse, which of the following practices best reduces the risk of fungal diseases?
A
High humidity and low ventilation
B
Adequate airflow and proper spacing between plants
C
Frequent watering with tap water
D
Overcrowding plants for maximum yield
Correct Answer: B
Good ventilation and spacing reduce humidity and allow air circulation, limiting fungal growth.
Junior Certificate Examination
Agricultural Science
Q1541.
What does the term "photosynthetic efficiency" refer to?
A
The ratio of light absorbed to light reflected
B
The proportion of absorbed light converted into chemical energy
C
The amount of water used per unit of biomass
D
The speed of nutrient uptake by roots
Correct Answer: B
Photosynthetic efficiency measures how effectively a plant converts absorbed light into sugars.
Junior Certificate Examination
Agricultural Science
Q1542.
Which of the following is a typical method for controlling nematodes in soil?
A
Spraying with insecticides
B
Using nematicidal organic amendments like neem cake
C
Increasing soil pH above 8.0
D
Applying high doses of nitrogen fertilizer
Correct Answer: B
Nematicides, including organic options like neem, help manage root-knot nematodes.
Junior Certificate Examination
Agricultural Science
Q1543.
In the context of climate-smart agriculture, which practice helps sequester carbon in the soil?
A
Continuous tillage
B
Deep ploughing
C
Conservation tillage and crop residue retention
D
Removing all vegetation from fields
Correct Answer: C
Conservation practices retain organic matter and reduce CO₂ emissions, enhancing soil carbon storage.
Junior Certificate Examination
Agricultural Science
Q1544.
Which of the following processes is primarily responsible for converting atmospheric nitrogen into a form usable by plants?
A
Photosynthesis
B
Nitrogen fixation
C
Respiration
D
Transpiration
Correct Answer: B
Biological nitrogen fixation converts atmospheric N₂ into ammonia, which plants can assimilate.
Junior Certificate Examination
Agricultural Science
Q1545.
In a crop rotation system, which rotation pattern is most effective for reducing the buildup of root‑borne pathogens in a field of tomatoes?
A
Tomato → Wheat → Corn → Tomato
B
Tomato → Potato → Peas → Tomato
C
Tomato → Legume → Legume → Tomato
D
Tomato → Sugarcane → Legume → Tomato
Correct Answer: C
Rotating tomatoes with legumes (which fix nitrogen) and another legume interrupts pathogen life cycles.
Junior Certificate Examination
Agricultural Science
Q1546.
Which of the following soil amendments increases the soil's cation exchange capacity (CEC) and is commonly used in acidic soils?
A
Lime
B
Gypsum
C
Dolomitic limestone
D
Phosphoric acid
Correct Answer: C
Dolomitic limestone supplies calcium and magnesium, raising CEC and correcting acidity.
Junior Certificate Examination
Agricultural Science
Q1547.
The "green revolution" introduced high‑yield varieties of which staple crop that dramatically increased food production in the 1960s?
A
Maize
B
Rice
C
Wheat
D
Sorghum
Correct Answer: B
High‑yield, semi‑dwarf rice varieties like IR8 were pivotal in the green revolution.
Junior Certificate Examination
Agricultural Science
Q1548.
Which of the following is a characteristic of a well‑structured agroforestry system?
A
Monoculture planting of fast‑growing trees
B
Intercropping trees with annual crops
C
Continuous clear‑cutting of forest land
D
Exclusive use of chemical fertilizers
Correct Answer: B
Agroforestry combines trees and crops to enhance biodiversity and soil health.
Junior Certificate Examination
Agricultural Science
Q1549.
In the process of composting, which of the following environmental conditions is most critical for the rapid decomposition of organic matter?
A
Low temperature and high moisture
B
High temperature and low moisture
C
High temperature and high moisture
D
Low temperature and low moisture
Correct Answer: C
Thermophilic composting requires high temperature (50–70 °C) and adequate moisture for microbial activity.
Junior Certificate Examination
Agricultural Science
Q1550.
Which of the following is NOT a primary benefit of integrated pest management (IPM) over conventional pesticide use?
A
Reduced pesticide residues on food
B
Lower risk of pest resistance
C
Immediate elimination of all pests
D
Preservation of beneficial insects
Correct Answer: C
IPM aims for sustainable control, not instant eradication of all pests.