Automated PLE Science Exam Paper Generator

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

(a) Silting is the deposition and accumulation of eroded soil particles into water bodies. (b) Soil erosion (triggered by cultivating or overgrazing near river banks). (c) Any one of: Blocks the oxygen supply to aquatic animals. Destroys aquatic habitats and breeding grounds. Exposes fish to predators due to cloudy/turbid water.

✅ 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) 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) Raised dish drying rack (or Plate stand). (b) (i) Keeps plates away from crawling insects, dogs, and chickens (ii) Prevents mud and dust splashes from dirtying clean plates. (c) The ultraviolet (UV) rays of sunlight kill harmful bacteria on the plates.

💡 Examiner Deduction Warning: Award 4 marks for complete sanitation rationale.

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

(a) Paraffin is a corrosive poison. Inducing vomiting will cause the chemical to burn the throat and esophagus a second time as it flows back up, or it can be inhaled into the lungs. (b) Give them plenty of cold milk to coat the stomach lining and dilute the chemical, then rush them to a hospital immediately. (c) Induce vomiting to remove the toxic substance from the stomach and give them milk to dilute the toxic concentrations. 💡 Would you like me to compile these exact evaluation questions into a ready-to-print, beautifully formatted PDF worksheets file for your classroom tests?

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

(a) (i) Zinc can (negative terminal). (ii) Carbon / Graphite rod with brass cap (positive terminal). (b) It acts as the chemical electrolyte that allows ionic conduction of charges. (c) The active chemicals (zinc and ammonium chloride) are completely consumed by the chemical reaction.

💡 Examiner Deduction Warning: Zinc serves as both the container and the negative terminal.

✅ 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) Dehydration (loss of water and essential mineral salts). (b) Any two of: Sunken eyes, dry lips, pale skin that does not snap back when pinched, or extreme body weakness. (c) Administering Oral Rehydration Solution (ORS) or extra fluids like coconut water.

✅ 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 4Fs / 5Fs Germ Path. (b) Any two of: Cholera, Typhoid fever, Dysentery, or Diarrhoea. (c) Covering all cooked food with clean lids (or keeping food in a sterile food mesh cabinet).

✅ 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) 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) Any two: Tendons, Ligaments, Cartilage. [1 mark] (b) A tendon attaches muscle to bone, whereas a ligament joins bone to bone at a joint. [1 mark] (c) (i) Synovial fluid lubricates the articulating bone surfaces. (ii) Smooth articular cartilage cushions bone ends and prevents direct bone-to-bone contact. [2 marks]

💡 Examiner Deduction Warning: Use the mnemonic BLB (Bone-Ligament-Bone) and MTB (Muscle-Tendon-Bone) to prevent reversing definitions in part (b).

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

Epididymis: Stores sperm cells to mature. Scrotum: Maintains a cooler temperature for sperm production. Cervix: Protects the developing fetus from physical damage. Vas deferens: Carries mature sperm cells to the urethra.

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

(a) Siltation is the deposition and accumulation of eroded soil particles into water bodies. (b) Soil erosion. (c) Any two of: It causes flooding in local compounds. It blocks food and light for aquatic life. It reduces the oxygen supply to fish, leading to death.