Automated PLE Science Exam Paper Generator

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) (i) Two parallel lines: one long thin line (+) and one short thick line (-). (ii) A line with a gap and a raised lever not making contact. (b) 1. Each bulb operates at full voltage and glows brightly. 2. If one bulb burns out or is switched off, the remaining bulbs in other branches stay on.

💡 Examiner Deduction Warning: Independent branch operation is the main advantage of parallel circuits.

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) Accept any one of: - Weeds compete with crops for sunlight, water, space, and soil nutrients - Weeds harbor insect pests - Weeds spread plant diseases - Weeds make harvesting difficult (b) Accept any two of: - Hand weeding (slashing / uprooting) - Mulching the garden - Practicing crop rotation - Planting cover crops - Digging / hoeing weeds (c) Staking / trellising / propping (providing support to climbing stems)

💡 Examiner Deduction Warning: Cognitive Level: Comprehension & Application (C & A).

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) Soil drainage (or water retention capacity / porosity) (b) To prevent soil particles from falling into the collecting beaker / to filter soil from water (c) Sand soil drained fastest; because sand soil has larger particles with larger air spaces (pore spaces) that allow water to pass freely

💡 Examiner Deduction Warning: Cognitive Level: Application (A).

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) A short circuit is an accidental direct connection between live and neutral wires with near-zero resistance, resulting in dangerously high current flow. (b) 1. Frayed, worn-out, or damaged insulation on cables. 2. Overloading multi-plug sockets with heavy appliances. (c) Ordinary water contains dissolved minerals and is a good electrical conductor, which will shock and electrocute anyone attempting to put out the fire.

💡 Examiner Deduction Warning: Never use water on electrical fires—use dry powder or carbon dioxide fire extinguishers.

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) The tin can crushed / collapsed inward. (b) Cold water condensed the steam inside into liquid water, creating a partial vacuum (low air pressure) inside. The higher atmospheric air pressure outside crushed the can inward. (c) Condensation (gas/steam turning into liquid water).

💡 Examiner Deduction Warning: A classic 4-mark PLE question.

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) Agroforestry is the agricultural practice of growing crops, planting trees, and keeping livestock on the same piece of land at the same time. (b) Accept any one of: - Fast growing - Leguminous (fix nitrogen in the soil) - Deep-rooted (does not compete with crop roots) - Have multipurpose uses (provide fodder, firewood, fruits) (c) Accept any two of: - Provides an additional source of income and food/timber - Improves soil fertility through fallen leaf litter and nitrogen fixation - Trees act as windbreaks and control soil erosion - Leaves provide fodder for livestock

💡 Examiner Deduction Warning: Cognitive Level: Comprehension & Application (C & A).

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(i) Sorting: Separates clothes by color to prevent staining, and by texture/dirtiness to protect delicate fabrics. (ii) Soaking: Softens and dissolves stubborn dried dirt and stains, making scrub-washing easier.

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) Identical twins are formed from one ovum fertilized by one sperm cell which later splits, while fraternal twins are formed from two separate ova fertilized by two different sperm cells. (b) 1. They are always of the same sex. 2. They look exactly alike (have identical features).

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) An ordinary pit latrine requires a tight-fitting lid over its drop hole, whereas a VIP latrine must be left open without a lid at all times. (b) Wood ash (or soil/lime) is sprinkled over the feces. Its role is to dehydrate the waste, neutralize smells, and raise pH to destroy pathogens. (c) Never throw hard materials (like stones, pads, or newspapers) into the bowl to prevent blockage. TOPIC 12: THE REPRODUCTIVE SYSTEM

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) Social insects. (b) Some insects are eaten as food (grasshoppers), some pollinate crops, or some provide honey and wax (honeybees). (c) Any two of: Bush burning, Deforestation, Spraying chemical pesticides, or Swarm/wetland drainage.

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) (i) Sanitation: The general cleanliness of the environment to promote public health / steps taken to keep an area clean. (ii) Personal hygiene: The cleanliness of the body and the materials used to clean it. (b) Accept any two of: - Sweeping rubbish from the compound - Picking up littered rubbish and disposing of it in dustbins or rubbish pits - Slashing tall grass and clearing bushes around the compound - Draining stagnant water to destroy mosquito breeding grounds - Scrubbing and cleaning latrines and urinals regularly

💡 Examiner Deduction Warning: Cognitive Level: Knowledge & Application (K & A).

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) Accept any two of: - Causes liver cirrhosis (liver damage) - Causes high blood pressure and heart attacks - Causes brain and nerve damage (loss of memory / coordination) - Causes stomach ulcers (b) Accept any two of: - Leads to domestic violence and child neglect - Leads to poverty through wasting family income on alcohol - Leads to family breakdown and divorce - Leads to loss of jobs and unemployment

💡 Examiner Deduction Warning: Cognitive Level: Comprehension & Application (C & A).

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) Afforestation is the massive planting of trees in an area where there have never been trees before. (b) (i) To get land for farming and settlement (ii) To get wood fuel (firewood and charcoal) and timber. (c) Tree roots that absorb excess rainwater are destroyed, and bare soil easily allows rapid surface runoff into rivers and lakes.

💡 Examiner Deduction Warning: Mark strictly on environmental cause-and-effect.

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) To suck out foul odours from the pit and expel them high into the air. (b) To trap flies so they cannot escape and spread disease germs. (c) (i) Wind blowing across the top of the vent pipe draws out smelly gases continuously (ii) The latrine interior is kept dark, forcing air currents up the pipe.

💡 Examiner Deduction Warning: Classic 4-mark UNEB sanitation question.

✅ Official UNEB Section B Scoring Guide (Total: 4 Marks):

(a) (i) Oxygen (O2) (ii) Carbon dioxide (CO2) (b) Accept any two of: - Blows off roofs of houses and destroys buildings - Causes soil erosion (wind erosion) - Spreads airborne diseases and raises blinding dust - Blows down and destroys crops in gardens - Causes boat accidents on water bodies

💡 Examiner Deduction Warning: Cognitive Level: Knowledge & Application (K & A).