WAEC SSCE - Agricultural Science - 2003 (Practical)
Question 1 Rapport
(a) State three functions and two methods of maintaining each of specimens F (HOE), H (RAKE), and K (PLIERS).
Specimens: F (HOE), H (RAKE), K (PLIERS)
F (HOE)
Three functions:
- Used for tilling/loosening the soil for planting.
- Used for weeding and clearing between crops.
- Used for making ridges, heaps and seed beds.
Two methods of maintenance:
- Clean off soil and wash after use, then dry to prevent rusting; oil the metal part.
- Sharpen the blade regularly and keep the handle firm; store in a dry place.
H (RAKE)
Three functions:
- Used for gathering weeds, dry leaves and refuse on the farm.
- Used for levelling the soil surface and seed beds.
- Used for covering broadcast seeds lightly with soil and loosening the surface.
Two methods of maintenance:
- Clean off soil and debris after use, dry the metal head and oil it to prevent rust.
- Tighten and repair any loose teeth or handle, and store in a dry shed.
K (PLIERS)
Three functions:
- Used for gripping and holding objects firmly.
- Used for cutting and twisting wires (for example in fencing).
- Used for pulling out or fixing nails and staples.
Two methods of maintenance:
- Clean and wipe dry after use, and oil the joint/pivot to keep it moving freely and rust-free.
- Keep the jaws and cutting edges sharp and store in a dry tool box.
Détails de la réponse
Specimens: F (HOE), H (RAKE), K (PLIERS)
F (HOE)
Three functions:
- Used for tilling/loosening the soil for planting.
- Used for weeding and clearing between crops.
- Used for making ridges, heaps and seed beds.
Two methods of maintenance:
- Clean off soil and wash after use, then dry to prevent rusting; oil the metal part.
- Sharpen the blade regularly and keep the handle firm; store in a dry place.
H (RAKE)
Three functions:
- Used for gathering weeds, dry leaves and refuse on the farm.
- Used for levelling the soil surface and seed beds.
- Used for covering broadcast seeds lightly with soil and loosening the surface.
Two methods of maintenance:
- Clean off soil and debris after use, dry the metal head and oil it to prevent rust.
- Tighten and repair any loose teeth or handle, and store in a dry shed.
K (PLIERS)
Three functions:
- Used for gripping and holding objects firmly.
- Used for cutting and twisting wires (for example in fencing).
- Used for pulling out or fixing nails and staples.
Two methods of maintenance:
- Clean and wipe dry after use, and oil the joint/pivot to keep it moving freely and rust-free.
- Keep the jaws and cutting edges sharp and store in a dry tool box.
Question 2 Rapport
(a) State the main nutrient obtainable from each of the Specimen G (BONE), and P ( DRIED ANIMAL BLOOD) and two main nutrients obtainable from Specimen T (FISH)
(b) State three functions for each of the two main nutrients obtainable from specimen T
(c) Name one feed ingredient that can be prepared from each of specimens G, P, and T.
(d) Give two disadvantages of using the ingredient prepared from specimen P in compounding livestock feed.
Specimens: G (BONE), P (DRIED ANIMAL BLOOD), T (FISH)
(a) Main nutrient(s) obtainable
- G (Bone): mineral (calcium and phosphorus).
- P (Dried animal blood): protein.
- T (Fish): protein and mineral (calcium/phosphorus); also oil/fat.
(The two main nutrients from T are protein and minerals.)
(b) Three functions of each of the two main nutrients from T
Protein:
- Builds new body tissues for growth.
- Repairs worn-out tissues in the body.
- Forms enzymes, hormones and antibodies, and is used for egg/milk formation.
Minerals (calcium and phosphorus):
- Form and strengthen bones and teeth (and egg shells in poultry).
- Aid blood formation and clotting and muscle/nerve function.
- Help in metabolic processes and maintain the body's acid-base balance.
(c) One feed ingredient prepared from each specimen
- G (Bone): bone meal.
- P (Dried animal blood): blood meal.
- T (Fish): fish meal.
(d) Two disadvantages of using blood meal (from P) in compounding livestock feed
- It is unpalatable and has a strong odour, so animals may reject feed containing much of it.
- It is deficient in some amino acids and can easily spoil or become rancid, and may spread disease if not properly processed.
Détails de la réponse
Specimens: G (BONE), P (DRIED ANIMAL BLOOD), T (FISH)
(a) Main nutrient(s) obtainable
- G (Bone): mineral (calcium and phosphorus).
- P (Dried animal blood): protein.
- T (Fish): protein and mineral (calcium/phosphorus); also oil/fat.
(The two main nutrients from T are protein and minerals.)
(b) Three functions of each of the two main nutrients from T
Protein:
- Builds new body tissues for growth.
- Repairs worn-out tissues in the body.
- Forms enzymes, hormones and antibodies, and is used for egg/milk formation.
Minerals (calcium and phosphorus):
- Form and strengthen bones and teeth (and egg shells in poultry).
- Aid blood formation and clotting and muscle/nerve function.
- Help in metabolic processes and maintain the body's acid-base balance.
(c) One feed ingredient prepared from each specimen
- G (Bone): bone meal.
- P (Dried animal blood): blood meal.
- T (Fish): fish meal.
(d) Two disadvantages of using blood meal (from P) in compounding livestock feed
- It is unpalatable and has a strong odour, so animals may reject feed containing much of it.
- It is deficient in some amino acids and can easily spoil or become rancid, and may spread disease if not properly processed.
Question 3 Rapport
(a) Identify specimens L, N, and Q
| Specimen L; | Specimen N; | Specimen Q; |
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|
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(b) State three agricultural uses of each specimen N and Q
(c) List two crops each which require each of the specimens L, N and Q in large quantities for good yields
(d) State three methods of applying specimen L on a farm
(a) Identification of specimens
- Specimen L: Urea (a nitrogenous fertilizer).
- Specimen N: Lime (quicklime / slaked lime).
- Specimen Q: Wood ash.
(b) Three agricultural uses of each of specimens N and Q
Specimen N (Lime):
- It is used to correct soil acidity.
- It supplies calcium for root development and improves the structure of clay soils.
- It is used to correct water acidity and reduce turbidity in fish ponds by flocculating fine clay particles.
Specimen Q (Wood ash):
- It is used to correct soil acidity.
- It provides potassium for plant growth and is a good component of compost.
- It serves as a natural pesticide for controlling insect pests of seedlings and vegetables (and increases phytoplankton growth in fish ponds).
(c) Two crops each that require the specimens in large quantities for good yields
| Specimen | Two crops |
|---|---|
| L (Urea) | Maize; Rice (also millet, guinea corn, wheat, leafy vegetables) |
| N (Lime) | Groundnut; Cowpea (also soya bean, pigeon pea, bambara groundnut) |
| Q (Wood ash) | Cassava; Yam (also cocoyam, sweet potato, Irish potato, carrot) |
(d) Three methods of applying specimen L (urea) on a farm
- Ploughing or drilling it into the soil.
- Ring method (placing it round the plant) and covering it with soil.
- Side dressing and covering, or broadcasting it evenly over the field.
Détails de la réponse
(a) Identification of specimens
- Specimen L: Urea (a nitrogenous fertilizer).
- Specimen N: Lime (quicklime / slaked lime).
- Specimen Q: Wood ash.
(b) Three agricultural uses of each of specimens N and Q
Specimen N (Lime):
- It is used to correct soil acidity.
- It supplies calcium for root development and improves the structure of clay soils.
- It is used to correct water acidity and reduce turbidity in fish ponds by flocculating fine clay particles.
Specimen Q (Wood ash):
- It is used to correct soil acidity.
- It provides potassium for plant growth and is a good component of compost.
- It serves as a natural pesticide for controlling insect pests of seedlings and vegetables (and increases phytoplankton growth in fish ponds).
(c) Two crops each that require the specimens in large quantities for good yields
| Specimen | Two crops |
|---|---|
| L (Urea) | Maize; Rice (also millet, guinea corn, wheat, leafy vegetables) |
| N (Lime) | Groundnut; Cowpea (also soya bean, pigeon pea, bambara groundnut) |
| Q (Wood ash) | Cassava; Yam (also cocoyam, sweet potato, Irish potato, carrot) |
(d) Three methods of applying specimen L (urea) on a farm
- Ploughing or drilling it into the soil.
- Ring method (placing it round the plant) and covering it with soil.
- Side dressing and covering, or broadcasting it evenly over the field.
Question 4 Rapport
(a) (i) Describe the physical properties of each of Specimens B (SAND), C (CLAY), and D (LOAM)
(ii) To about 10ml each of the specimens B, C and D, add about 5ml of specimen O and using the hand, mix well. Describe the physical properties of each specimen?
(b) Which of the specimens B, C, and D should be considered of greater value to farmers? Give two reasons for your answers
(c) State three ways of improving each of the other two specimens not mentioned in (b) above
Specimens: B (SAND), C (CLAY), D (LOAM), O (WATER)
(a)(i) Physical properties of the dry specimens
| Property | B (Sand) | C (Clay) | D (Loam) |
|---|---|---|---|
| Texture (feel) | Coarse and gritty | Smooth and sticky when wet, hard when dry | Slightly gritty and crumbly (medium) |
| Particle size | Large particles | Very fine particles | Mixture of large and fine particles |
| Colour | Usually pale/whitish or light brown | Grey/reddish, often darker | Dark brown/blackish |
| Structure | Loose, single grains | Compact, cloddy | Crumbly, well aggregated |
(a)(ii) After adding water (specimen O) and mixing
| Specimen | Observation on adding water |
|---|---|
| B (Sand) | Water drains through quickly; does not hold water; cannot be moulded and falls apart easily. Low water-holding capacity. |
| C (Clay) | Water is retained; becomes very sticky, plastic and can be rolled/moulded into a ball or ribbon. High water-holding capacity, poor drainage. |
| D (Loam) | Holds some water yet drains the excess; becomes moist and can be moulded but not too sticky. Moderate water-holding capacity, good drainage. |
(b) Specimen of greater value to farmers: D (LOAM)
Two reasons:
- It has a good balance of sand, silt and clay, giving it good water-holding capacity together with good drainage and aeration.
- It is rich in humus and plant nutrients and is easy to work, so it supports most crops well.
(c) Three ways of improving each of the other two specimens
Sand (B):
- Add organic manure or compost to improve water and nutrient retention.
- Add clay and apply mulch to reduce water loss.
- Practise cover cropping and grow leguminous crops to build up humus.
Clay (C):
- Add coarse sand and organic matter to improve aeration and drainage.
- Apply lime to improve its structure (flocculation) and reduce stickiness.
- Provide good drainage channels and practise deep ploughing to loosen it.
Détails de la réponse
Specimens: B (SAND), C (CLAY), D (LOAM), O (WATER)
(a)(i) Physical properties of the dry specimens
| Property | B (Sand) | C (Clay) | D (Loam) |
|---|---|---|---|
| Texture (feel) | Coarse and gritty | Smooth and sticky when wet, hard when dry | Slightly gritty and crumbly (medium) |
| Particle size | Large particles | Very fine particles | Mixture of large and fine particles |
| Colour | Usually pale/whitish or light brown | Grey/reddish, often darker | Dark brown/blackish |
| Structure | Loose, single grains | Compact, cloddy | Crumbly, well aggregated |
(a)(ii) After adding water (specimen O) and mixing
| Specimen | Observation on adding water |
|---|---|
| B (Sand) | Water drains through quickly; does not hold water; cannot be moulded and falls apart easily. Low water-holding capacity. |
| C (Clay) | Water is retained; becomes very sticky, plastic and can be rolled/moulded into a ball or ribbon. High water-holding capacity, poor drainage. |
| D (Loam) | Holds some water yet drains the excess; becomes moist and can be moulded but not too sticky. Moderate water-holding capacity, good drainage. |
(b) Specimen of greater value to farmers: D (LOAM)
Two reasons:
- It has a good balance of sand, silt and clay, giving it good water-holding capacity together with good drainage and aeration.
- It is rich in humus and plant nutrients and is easy to work, so it supports most crops well.
(c) Three ways of improving each of the other two specimens
Sand (B):
- Add organic manure or compost to improve water and nutrient retention.
- Add clay and apply mulch to reduce water loss.
- Practise cover cropping and grow leguminous crops to build up humus.
Clay (C):
- Add coarse sand and organic matter to improve aeration and drainage.
- Apply lime to improve its structure (flocculation) and reduce stickiness.
- Provide good drainage channels and practise deep ploughing to loosen it.
