Summary

• Description:

  The PDF document comprises KALA Trial Biology Paper 1 2026 Mock Exam with Marking Scheme. The marking scheme is in a different document.

  It was a KCSE Biology Paper 1 (231/1) mock examination administered for secondary school revision.

  This assessment targets core competencies in physiological processes, human anatomy, evolutionary mechanisms, genetic crosses, ecological dynamics, and cell biology to boost revision mastery and examination scores.

  • Month Administered: July 2026
  • Duration: 2 Hours
  • Total Marks: 80 Marks
  • Number of Questions: 24 Questions (Questions 1 - 24)
  • Structure: Single compulsory theory paper containing short-answer and structured data-response questions

  It covers the following topics:

  • Branches of biology: embryology and anatomy
  • Cell physiology, osmoregulation, and active transport in Protoctista (Amoeba) vs Monera
  • Digestive system: gastric secretions, intestinal crypts, and herbivore digestion
  • Irritability and response: phototaxis in Euglena versus phototropism in plant shoots
  • Coordination and the nervous system: anatomy and functions of the human brain
  • Evolution and adaptation: industrial melanism, homologous/analogous structures, and insect skeletal systems
  • Plant reproduction and development: seed structure, physiological dormancy, inflorescences, and ovary position
  • Enzyme action: digestion of starch by diastase and factors affecting enzyme activity
  • Genetics and variation: monohybrid inheritance of dominant chin dimples and discontinuous human traits
  • Photosynthesis: factors affecting the rate of photosynthesis in aquatic plants
  • Circulatory system: functions of the pericardium, sites of erythropoiesis, and gaseous exchange surfaces
  • Human and mammalian skeletal system: cranial structures, functions, and mammalian dental formulas
  • Reproduction in mammals: male reproductive anatomy and physiological functions of testes, epididymis, and prostate
  • Ecology: nitrogen cycle bacteria and differences between scavengers and detritivores
  • Excretion and homeostasis: definition, nitrogenous waste elimination, oxygen debt, and desert mammalian nephron adaptations
  • Microscopy: light microscope mechanics and electron microscopy specimen preparations
  • Cell division: meiotic synapsis, bivalent formation, and comparisons between mitosis and meiosis
  • Environmental pollution: greenhouse effect and respiratory poisoning from fumes
  • Respiration: calculating respiratory quotient (RQ) and comparative substrate energy values
• File Size:

  579.87 KB
• Length:

  12 pages
• Category:

  Mock Past Papers
• Level:

  Form 4
• Subject:

  Biology
• Posted By:

  Caleb_Peter

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