Automated PLE Science Exam Paper Generator

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

(a) Accept any two of: - High environmental temperature / dry hot weather - High fever - Direct injury or physical blow / punch to the nose - Nose picking (damaging delicate blood vessels) - Rupture of delicate blood capillaries due to high blood pressure (b) Accept any two of: - Pinching the soft part of the nose firmly for 5 to 10 minutes - Applying a cold compress or ice pack over the bridge of the nose - Leaning the head slightly forward (never backward, to prevent swallowing blood) - Loosening tight clothing around the neck and chest

💡 Examiner Deduction Warning: Cognitive Level: Application (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) 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) 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) Accept any two of: - Crushed oyster shells / snail shells - Crushed eggshells - Bone meal (crushed animal bones) - Crushed Mukene fish (b) Accept any two of: - Feeding layers on a balanced diet rich in calcium and proteins - Providing clean fresh drinking water at all times - Vaccinating and deworming birds regularly to control diseases - Maintaining clean, well-ventilated, and dry poultry housing with comfortable laying nests - Providing adequate artificial light to stimulate laying

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

✅ 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) Gas state / Gaseous state (b) (i) Sublimation (ii) Freezing / Solidification (c) Camphor / Iodine crystals / Ammonium chloride / Dry ice (solid carbon dioxide)

💡 Examiner Deduction Warning: Cognitive Level: Knowledge & Comprehension (K & C).

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

(a) Tsetse fly (b) Larva stage (maggots) / Adult fly (c) Blood (from humans and livestock) (d) Through biting and sucking blood (injects saliva containing Plasmodium parasites)

💡 Examiner Deduction Warning: Cognitive Level: Knowledge & Comprehension (K & C).

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

(a) To prevent the sow from rolling over and crushing her piglets to death. (b) To allow urine and droppings to fall through so the floor stays dry, preventing foot rot. (c) (i) Drenching / Deworming (ii) Hand spraying / vaccination / hoof trimming.

💡 Examiner Deduction Warning: Standard 4-mark UNEB livestock question.

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

(a) (i) Black jack: Animal dispersal (epizoochory) (ii) Sycamore: Wind dispersal (b) Accept any two of: - Have wing-like structures (e.g. sycamore) - Have parachute of fine hairs / pappus (e.g. dandelion, tridax) - Are very small and light in weight - Are dust-like (e.g. orchids)

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

✅ 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) A physical change does not take place in living things and is reversible, whereas a biological change takes place exclusively in living organisms and is irreversible. (b) (i) Melting (ii) Evaporation / Boiling (c) Evaporation

💡 Examiner Deduction Warning: Clear distinction in reversibility and living vs non-living matter.

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

(a) Chemical change (b) Physical change (c) Biological change (d) Physical change

💡 Examiner Deduction Warning: Cognitive Level: Comprehension (C). Exactly 1 mark per correct classification.

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

(a) The gradual introduction of semi-solid and solid complementary foods to an infant alongside breast milk. (b) At 6 months of age. (c) The infant's digestive system is immature and cannot digest solid starches (or high risk of contamination/diarrhea). (d) Plain porridge lacks protein and causes Kwashiorkor.

💡 Examiner Deduction Warning: Mark strictly on age (6 months) and digestive maturity.

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

(a) Primary Health Care. (b) (i) Community participation (ii) Affordability / Accessibility / Equity / Appropriate technology. (c) Because preventive measures (sanitation, clean water, immunisation) cost very little compared to expensive drugs and hospital admission.

💡 Examiner Deduction Warning: Reward clear economic and social understanding.